I am also posting this on the Varmint Shooting forum...so hear ya go...



Forums are always filled with armchair ballisticians, who inform we reloaders of what we should and shouldn’t do, because they read in some book or in some article.. “ Yadda Yadda Yadda..â€.. and then they present themselves as an expert on the subject, using the article or book as a reference to back them up…

Well some of we reloaders have taken offense to this at times.. yet when we point out something to these folks, we are rewarded with getting flamed, name called etc..
And then told we have no proof to back up what we say and we are going to hurt someone…

I am working up a load to use in a Ruger 77 Mk2 sporter weight 22.250 with a 22 inch barrel. I have picked the bullet weight of 50 grains for the application. I have picked several powders to load and try out….

The two I want to relate to the above is BLC 2 and Benchmark.

Hodgdon’s Annual Manual for 2004 lists a charge of 34.5 grains as a max charge with a pressure of 48,400 CUP.. and an MV of 3740 fps.

Older manuals and Steve Riccardelli’s site list a max charge of 38.5 grains with this same powder, although no pressure was listed that I can find for this charge, nor was any MV given.

Well testing the 34.5 grain Load over my chronograph, my MV came up a little short on what was listed in the manual.. 350 fps short to be exact. Several shots with my 22 inch barrel Ruger gave an MV of 3390 fps.. none were higher than that.

So next I worked up loads with 36 grains and 38.5 grains listed as max from other sources…Now according to our ‘on line’ armchair ballisticians exceeding the 34.5 grain load would be “Idioticâ€.. “Dangerous†etc…. However, the 36 grain load and the 38.5 grain loads were just fine… they would have been quick to point out that the 38.5 grain load was more than 10% over the recommended max… I would have been accused of potentially killing someone….

Instead of killing some one this shows the importance of “working up†your loads….. and also manuals are strictly that, a reference… Plus it shows the importance of a chronograph… 2 rifles and 8 reloads of the same charge failed me to get within 350 fps of the MV listed in the reference… even tho I used the same primer and powder charge.


Now lets take a look at the Benchmark loads…

The same reference manual recommends a charge of 36 grains as max, for an MV of 3903 fps, and a pressure of 51,400 CUP, which is still below SAAMI pressure specs for this cartridge.

Well the old chronograph was out testing the real world also with this load.
First of all, I quit testing the max 36 grain load, when the third primer out of 3 blew in the rifle…. So the load listed in the manual was too hot for that Ruger 22.250 Sporter. I also tried a couple in a Ruger VT in 22.250.. the loads were too hot for that rifle also.

So contrary to our “ online†armchair ballistic experts, what is listed as max in a manual or reference material IS NOT what is always safe.. two different rifles wouldn’t take this load without blowing primers.. they extracted, but did blow the primers.. Once again another proof to ‘working up†a load.. Just because the “manual†says it will be safe in your rifle doesn’t mean it will….

So I dropped down to 35.5 grains and 35 grains to test those out. Both of those loads were safe in both of my rifles.. although the chronograph had me wondering what the pressures were, if just half a grain more was eating primers….

The chronograph also told me some more info. At 36 grains the MV was supposed to be 3903 fps or so. Well at 35.5 grains, the MV turned out to be between 3988 and 3994 fps… 100 fps faster with Half a grain of less powder.. Hmmm…

Another deviation from the theories of our armchair ballistician experts…. Looks like manuals make a good reference, not a good Bible on the subject.

Now the 35 grain loads… they had MVs ranging from 3820 fps to 3909 fps….wide deviation spread, yet the loads were accurate in that rifle. Still some more deviation from the “gospel according to†the Hodgdon Manual….

And finally lets look at the chronograph itself. I have had forum members tell me many times that my chronograph must be registering things faster than what they really are, because it registers faster velocities with loads, than they get with their chronograph or according to their reload manual’s listed MVs…

Well those that say “each rifle is an entity onto itself†are the only ones that are really correct.

In the case of BLC2, my chrony was listing MVs at least 350 fps slower than the book model’s results.

Yet on the same page and same manual, when using Benchmark Powder, my chronograph was registering results 100 fps faster, with ½ grain less powder…. And was equaling results the same as the reference manual with an entire grain of powder less…

So here is the same chrony, same day, same rifle… registering ONE load 350 fps slower than the manual stated… and registering another load 100 fps FASTER than the manual listed, and that was with a load ½ a grain less…..

So does that make my chrony slow or faster than actuality.. or can I just assume it is just perfectly fine and is recording what it sees??? I chose the latter analogy.

Quoting a good friends saying “ So what does it all mean???â€â€¦

Well, reference materials are just that, REFERENCE… Reload manuals are guides, not bibles. People, who just pass on what they read, don’t know what they are talking about in the real world of reloading, whether they flame you in the process or hoop and holler with all the “authority†they can muster…. Effort doesn’t make them any more correct.

Both these examples also show the real importance of a chronograph and the importance of the information that it can give you.

Thirdly, the old advise of “Work UP†& every rifle is an entity onto itself, holds truth.
Hodgdon is probably accurately reporting the actual results that they received in their testing. But the results their rifle got and the results my rifles got, varied dramatically.
ONE varied to be equal to a lot less ( 350 fps less), while the other load was blowing primers in two different rifles… and both of them got 100 fps more velocity, with ½ a grain of less powder…..

No amount of reading can replace at the reload bench and at the range experience..

Cheers
Seafire
January 1, 2008

I'v never used Benchmark but I have used BL-C(2) in the 22-250 and I got much less than expected velocity....

I'm sticking with H-380 and H-414

Your logic is absolutely correct and I agree completely.

I have always used loading manuals only as a starting point and decide what is a max load in a particular rifle based on pressure indicators.

In some cases this means I am exceeding book maximum and in others I cannot reach book max without showing leaky or blown primers.

A load that is listed as maximum in any manual does not indicated that it is safe to use in any particular rifle - only the one that was used during the testing.

Always work up your loads - and pay attention to what your ammunition and rifle is telling you.

To do otherwise is to invite the wrath of the GUN GODS.

Seafire,

You are soooo correct about "each rifle is unique unto itself!" Any reloading manual will tell you that you should work the load up because of this fact.

That said, try this little trick sometime. I started doing this some years ago, and it really is interesting and revealing.

When working up a load, I know what bullet I want to use, and I know what powders I have in stock that are appropriate for my cartridge.

Using the 3 or 4 reloading manuals, I try to figure out the median load for that cartridge with that bullet.

I then load one cartridge of each powder I wish to try. I shoot them across the chronograph to note which powder provides the closest velocity to what the manuals say I should get. Most powders provide substantially less velocity, but there always seems to be one out of 4 or 5 powders that is close to published velocity.

My 25-06 was a classic example. I wanted to load a 75 gr. V-Max, but none of the powders/loads I was getting from the manuals were performing as predicted. So I started over using the process I described. I also found a load for IMR3031 that only one manual listed. I loaded 1 of each median load and shot them across the chronie.

Well, you guessed it... the load for 3031 gave me the best velocity and worked up to be a very accurate and deadly load. Yet, only the IMR manual listed that load!

Finally, don't let some of the folks on here get your goat. Remember, it's your goat!!... they have their own goat to mess with!!

quote:

Originally posted by seafire2:
...Yet on the same page and same manual, when using Benchmark Powder, my chronograph was registering results 100 fps faster, with ½ grain less powder…. And was equaling results the same as the reference manual with an entire grain of powder less…

So here is the same chrony, same day, same rifle… registering ONE load 350 fps slower than the manual stated… and registering another load 100 fps FASTER than the manual listed, and that was with a load ½ a grain less…....

Hey Seafire, Absolutely excellent way to begin the new year.

The above portion of your post clearly shows "Why" a person should not just keep dumping in Powder until some arbitrary, random picked Velocity is reached.

It is also "Why" chronographs have the potential to be misleading for the Beginners.

And it is also "why" people have seen some of us hammer on the folks who say you can't Reload without a chronograph. No doubt they can tell a person what the Velocity is, but they don't tell a thing about Pressure.

Congratulations on a great thread to start the new year.

One of the key words in your post was "experience" and until you have experience you have to have some sort of guide lines and a good deal of caution when dealing with things that can bite.
I agree that the chicken littles can become so shrill and strident that they lose credibility but "start low, work up slowly, and don't go above book max" is good advise for a newbie.
Once they have aquired the experience and a comfort level with reloading and decide they want to go beyond reloading good ammo for their hunting rifle(s), they usually aquire a chrony of some sort and discover just how many reloading doors this opens for them. Then the reloading manuals do indeed bcome more guide lines and less bibles. Chrony knowledge drives a good deal of the information in your post.
I think the whole key is having some sort of Chrony. Without one, and knowing how to interpete the data it gives you, you need some sort of limiting guide lines. Without a Chrony, what would you suggest?

Sea, I read your comments with a grin! Your observations are correct. I see a LOT of posts that demonstrate that a "little knowledge can be a misleading thing."

Besides your examples I get a chuckle out of those who agonize over OAL lengths that are listed in books, as if that were the only length that is safe and then only if they are consistant within one or two thousants. Bah. NO loading book even listed an OAL until a few years ago but half-knowledgeabe people have grabbed it as one point of "precision handloading", which, of course, it is not.

Ditto but less often, the whinning about how to find the exact point of contact between the bullet and the lands because "every smart loader knows that's where you get best accuracy." Of course that's not true either but...we can't convince them because they read it in some magazine.

And there are those who are determined that ammo made with RCBS dies and presses are absolutely ideal and anything done with Lee tools is junk. Not so. (I do agree that RCBS gear is just as good as Lee's but at much higher price so the vaunted warranty is covered at purchase and even that's no help if you aren't a mechanical klutz that breaks things from misuse.)

Ah, well. I used to try to correct some posters with the facts but got dissed so often that I now just read the foolishess and keep moving along.

Well said, Seafire! I KNOW you know that all rifles are individuals, and that each individual rifle has its' own maximum charge, and if you try to exceed it, the gun will let you know!! Your max load may bear no resemblance to what any book says, either as regards pressures or actual velocities. AND, your rifle's "max load" can be way over, or way under, the published MAX LOAD!

All the book is good for is giving you some idea of a safe starting point for load development purposes.

Least of all do I pay any attention to any "expert" who tells me that my load is "excessive". How the hell would he know?? Did he work up a load using those same components IN MY RIFLE?? NOPE!!

However, there is ONE WARNING I take seriously out of a loading manual, particularly those printed by powder makers: "MINIMUM LOAD - DO NOT REDUCE!!" This is a warning of possible SEE events. Since such things are random, I try never to give a gun a chance to have one!

Just curious... I know a lot of people use the 'book' velocity as an indicator that they have reached the MAX.

Can anyone explain where/how the 'books' come up with that figure and why it would be better or worse than other indicators?

Is it based on the velocity that they observed when the pressure gauge said 'enough'?

Wouldn't that number still be based on 'their rifle/primer/brass/barrel' and not indicative of how our setups would perform?

quote:

agree that the chicken littles can become so shrill and strident that they lose credibility but "start low, work up slowly, and don't go above book max" is good advise for a newbie.

Well Beeman,

one point I was trying to make, is that don't expect "book max" to be even that.. as I was pointing out, I had two rifles that wouldn't even reach book max... and that is damn good advise for newbies so that they don't assume that book max is always safe....

Not going over book max is good advise for a newbie, I agree... but I was trying to point out, just because it is in a book, don't assume that Book Max is going to be the Max in your rifle.. the max in your rifle can be less, and sometimes a lot less...

you also asked the question...
Without a Chrony, what would you suggest?

What would I suggest? My answer to that one is " If you don't have one, GET ONE!"...

a chrony can be purchased for the price of 5 boxes of regular bullets, or 500 bullets...or the price of 5 lbs of powder...

So there is no excuse for a handloader to say they are too expensive...

Being a reloader who is taking safety seriously, but tries to get by without a chrony, by saying it costs too much....
That makes about as much sense to me as someone who buys a car, lives in the mountains, and states that he decided not to order brakes on the car, because they cost too much extra....

As George Carlin use to say in his skit.. if you have a $10 head, buy a $10 helmet....

quote:

Just curious... I know a lot of people use the 'book' velocity as an indicator that they have reached the MAX.

Yes. Some do. Most consider the Powder charge to be the max indicator.

quote:

Can anyone explain where/how the 'books' come up with that figure and why it would be better or worse than other indicators?

No, too many variables.

quote:

Is it based on the velocity that they observed when the pressure gauge said 'enough'?

Yes.

quote:

Wouldn't that number still be based on 'their rifle/primer/brass/barrel' and not indicative of how our setups would perform?

Yes.

Here is the thing to keep in mind...

Reloading is the art of staying within acceptable ranges of variables.

Variables include, but are not limited to:
Every step in the manufacturing of a firearm (Barrel, Reciever, Bolt, Assembly)
Manufacturing of components (Primers, cases, powder, bullets)
Material quality of manufactured parts and components
Consistancy from Lot to Lot of manufactured components and parts

These are all dictated by SAAMI Specs within the industry. While each part of the equation has a +/- range, the combination of all the +/-'s can create some really big variables in the end result.

Still, it is amazing that a gun can hit anything at all, let alone put 5 shots into the same hole at 100 yds.

We are able to do that because, once you figure out the optimum range of variables that your gun likes, you can rely upon relative consistancy of your components in order to duplicate that performance with minimal adjustment.

At least, that is the theory.

With SAAMI Specs and exhaustive testing, reloading information is usually very sound, provided you follow strict proceedures regarding safety (start 10% below max and work up slowly, watching for signs of high pressure, never exceed max load, etc.).

If my velocity is way below the book says is a safe load, I just look for another powder that performs better. No sense in pushing the limits.

Wow ... and all this time I thought the elements of this diatribe fell into the "good reloading practices" category. (Also known as ... It's your a$$, start low and workup carefully!)

quote:

Originally posted by mstarling:
Wow ... and all this time I thought the elements of this diatribe fell into the "good reloading practices" category. (Also known as ... It's your a$$, start low and workup carefully!)

quote:

Originally posted by mike_elmer:

quote:

Just curious... I know a lot of people use the 'book' velocity as an indicator that they have reached the MAX.

Yes. Some do. Most consider the Powder charge to be the max indicator.

quote:

Can anyone explain where/how the 'books' come up with that figure and why it would be better or worse than other indicators?

No, too many variables.

quote:

Is it based on the velocity that they observed when the pressure gauge said 'enough'?

Yes.

quote:

Wouldn't that number still be based on 'their rifle/primer/brass/barrel' and not indicative of how our setups would perform?

Yes.

Here is the thing to keep in mind...

Reloading is the art of staying within acceptable ranges of variables.

Variables include, but are not limited to:
Every step in the manufacturing of a firearm (Barrel, Reciever, Bolt, Assembly)
Manufacturing of components (Primers, cases, powder, bullets)
Material quality of manufactured parts and components
Consistancy from Lot to Lot of manufactured components and parts

These are all dictated by SAAMI Specs within the industry. While each part of the equation has a +/- range, the combination of all the +/-'s can create some really big variables in the end result.

Still, it is amazing that a gun can hit anything at all, let alone put 5 shots into the same hole at 100 yds.

We are able to do that because, once you figure out the optimum range of variables that your gun likes, you can rely upon relative consistancy of your components in order to duplicate that performance with minimal adjustment.

At least, that is the theory.

With SAAMI Specs and exhaustive testing, reloading information is usually very sound, provided you follow strict proceedures regarding safety (start 10% below max and work up slowly, watching for signs of high pressure, never exceed max load, etc.).

If my velocity is way below the book says is a safe load, I just look for another powder that performs better. No sense in pushing the limits.

Thanks Mike. I see that you changed your response to the first question and that is what I was most curious about. Why would we think that the velocity that a test rifle/load exhibited be any more of a reliable indicator than the powder charge that they peaked at? I think that it's still just a relative number and good information. Not a hard and fast MAXIMUM.

I have been loading for 30 yrs and subscribe to the method of start lowish and work up until I hit a really accurate node. If, after that, I am substantially under 'book', I may try to increase the charge after that in small increments until I find another accuracy node or pressure signs start to appear. Then I break out the chrono to see where I'm at. Like you, if I am well under the velocities that have been reported, I will try another powder.

kelbro,

Yes, I read that first answer, and it just didn't satisfy me.

In one of my earlier posts, I mention using a method to select the right powder as one of the first procedures in working up a load. It saves me a lot of bullets and time when I use that method.

I actually take the mean of the means of the various loads for a powder and bullet combination. With 5 shots I can get a ball park idea of velocity for 5 different powders in my rifle.

Almost every time, there is one powder that stands out from the rest. It stands to reason that it is the most efficient powder for my gun.

Same here. No matter how much I would like for powder X to work, you can't force it! There is always one or two that really shine. I think your method would save a person a lot of powder, bullets, and range time.

quote:

Originally posted by mstarling:
Wow ... and all this time I thought the elements of this diatribe fell into the "good reloading practices" category. (Also known as ... It's your a$$, start low and workup carefully!)

This is what I love about being born in, and my family roots from West Va....

you don't need a PhD from Harvard or MIT to get a simple point across...

quote:

I think your method would save a person a lot of powder, bullets, and range time.

yeah but for some of us, there goes all the fun , right out the window!

quote:

Originally posted by seafire2:

quote:

I think your method would save a person a lot of powder, bullets, and range time.

yeah but for some of us, there goes all the fun , right out the window!

Well it seems like once I get a load dialed in and load a couple hundred, I get antsy and start looking at other bullets/powders and have to start all over again

Heck, in .223 bullets, I have 40gr, 53gr, a couple of different 55gr, 69gr, and 75gr loads all boxed up. .223 Powders: H335, BLC2, Varget, Blue Dot , and I just picked up 4# of Benchmark to try.

Reloading is going to start saving me money any day now...

quote:

Originally posted by stillbeeman:
... I think the whole key is having some sort of Chrony. Without one, and knowing how to interpete the data it gives you, you need some sort of limiting guide lines. Without a Chrony, what would you suggest?

Hey Stillbeeman, I agree with the approach offered by Kelbro:

quote:

Originally posted by Kelbro:
... start lowish and work up until I hit a really accurate node. If, after that, I am substantially under 'book', I may try to increase the charge after that in small increments until I find another accuracy node or pressure signs start to appear. Then I break out the chrono to see where I'm at. ...

The only significant difference I have with his Method is I don't waste time bothering to use a Chronograph.

Since it only tells Velocity, I've found that I can "guess" close enough to the Chronographed Velocity to get on paper. And then a person really should shoot to see how much the Actual Drop Rate happens to be, not just go by some computer generated math model.

Guessing at the Velocity is relatively easy. You simply compare the Load you are using to the Average Velocity of several Manuals for that same amount of Powder and then subtract 150fps. That Guess will be close enough to get you on the paper out at 300yds once you are sighted in at 100yds. And once a person realizes that, there is no need for any (misleading) Chronograph at all.

So for all the Beginners, you really do not need to waste money and time on a Chronograph. And those of you considering the totally worthless Haphazard Strain Gauge Systems(HSGSs), the esteemed Dr. Oehler will provide extremely insightful answers about them in this Thread. Basically, if you do not have a Certified Lab, you have wasted your money.

The old ways are quite often the best ways, because they have endured.

My point to not go above book max was not that book max was always permissible. In fact, that is not what I said. If I remember correctly, each book tells the beginning reloader, and it should be automatic to the experienced, to watch for pressure signs as he works TOWARD MAX.
Your point about how inexpensive a Chrony can be is well taken BUT have you ever looked at some of the "must have" list posted for a new reloader, this ONLY cost $10.00, that ONLY cost $5.00, and so forth. The total cost can be quite staggering. Especially if you start listening to the "I'll bet I can spend more money on my stuff than you can guys". When you consider just how many gazillions of rounds have been loaded using a Lee Loader, one has to wonder why we aren't all wondering around without any fingers or eyes.
I've used a Chrony since they first came out as an affordable option. And I strongly believe they should be among a reloader's first purchases after he learns the fundementals but they are still a "finesse" item.

Seafire,

I agree 100% with your points. I found out a long time ago (when I got my chronograph) that reloading manuals were to be taken with a large grain of salt. My findings were much the same as yours having several loads that were off from the listed manual velocities by several hundred fps. While a chronograph isn't a substitute for a dedicated pressure testing rig, the relationship between pressure and velocity is sufficiently known to be able to make educated guesses regarding pressure when you compare the velocity with the pressure data in the reloading manuals. A reloader with a chronograph has a lot more data at his hands to make informed decisions than one using any other method, especially one using the old discredited "case head expansion" method which makes me cringe any time I hear it mentioned. Anyone who's ever taken a college instrumental analysis class will recognize how that method has no functional basis in science.

The bottom line is that a chronograph is an extremely useful tool to the knowledgable reloader. It isn't the end all, be all, but it certainly does help to complete the picture of what your load is doing. I wouldn't be without mine.

A chronie is good for a couple of things. It lets me know which powder is performing most efficiently in my rifle chamber, and it lets me know if I am truly getting the hitting power I am seeking.

Other than that, I would contend it does little else. To assume that velocity and internal pressure have a consistant correlation is looking for trouble. There are too many other variables involved to safely make that assumption.

I am not willing to bet my fingers and face on it.

That said, I also would not critsize anyone for buying a Chrony and using it, or a pressure guage, or any other tool that they believe makes their reloading more accurate, consistant, practical and safe.

Mike is exactly right. Think about it.

Does the pressure/velocity change between a smooth, rough or in-between cut barrel? How about after a few rounds of fouling?

What about two similar barrels with the twist slightly different? Or the bore diameter .00001 different?

Hot, warm, or cold barrel?

Number of lands/grooves (even or odd)?

How about if the bullet alloys are slightly changed from lot to lot?

These and many other factors can significantly affect velocity or pressure and skew any supposed correlation between the two.

Velocity is just another data point that when plotted out in a statistical manner would display a lot of 'noise'. It is a good data point when considering ES and SD to determine if a load is performing consistently. I would not bet my fingers and face on it either.

kelbro,

Call it a hunch, but it's my guess you and I have rather handsome faces!!

"COLEGE INSTRUMENTAL ANALYSIS CLASS" ROFLMFAO
You've got to be kidding. If I hadn't copied it out of your post, I wouldn't have been able to spell that shit. I'm gonna guess that not one college grad out of 1000 has taken a COLLEGE INSTRUMENTAL ANALYSIS CLASS. I'm a college grad and I know I haven't. Until I read your post, I'd never even heard of it. Is that where they teach you to wear a hard hat and a lab coat and carry a clip board?
So now we've got to be MIT grads to operate a Lee Loader?

quote:

Originally posted by seafire2:

quote:

agree that the chicken littles can become so shrill and strident that they lose credibility but "start low, work up slowly, and don't go above book max" is good advise for a newbie.

Well Beeman,

one point I was trying to make, is that don't expect "book max" to be even that.. as I was pointing out, I had two rifles that wouldn't even reach book max... and that is damn good advise for newbies so that they don't assume that book max is always safe....

Not going over book max is good advise for a newbie, I agree... but I was trying to point out, just because it is in a book, don't assume that Book Max is going to be the Max in your rifle.. the max in your rifle can be less, and sometimes a lot less...

you also asked the question...
Without a Chrony, what would you suggest?

What would I suggest? My answer to that one is " If you don't have one, GET ONE!"...

a chrony can be purchased for the price of 5 boxes of regular bullets, or 500 bullets...or the price of 5 lbs of powder...

So there is no excuse for a handloader to say they are too expensive...

Being a reloader who is taking safety seriously, but tries to get by without a chrony, by saying it costs too much....
That makes about as much sense to me as someone who buys a car, lives in the mountains, and states that he decided not to order brakes on the car, because they cost too much extra....

As George Carlin use to say in his skit.. if you have a $10 head, buy a $10 helmet....

Seafire

I always seem to enjoy you posts and look forward to the experience that you share here on the board.

I agree with you on the importance of using a Chronograph and with many others who expressed agreement with the use of this tool. It can provide you with more information than just velocity when interpolated correctly.

But beware the 3 A$$holes, on this board will usually flame your undies for disagreeing with their theories. But then again who are they???

Love that ignore button!!

I've no axes to grind with boltman, but I do disagree with some of what he has posted.

quote:

Originally posted by boltman:
...the relationship between pressure and velocity is sufficiently known to be able to make educated guesses regarding pressure when you compare the velocity with the pressure data in the reloading manuals.

For all the Beginners, this is a simple misunderstanding of the usefullness of a chronograph. Following that incorrect thinking is the thing that has the potential to get people into High Pressure when they think everything is still fine.

Making any kind of Pressure assumption based on a Velocity is simply not what a chronograph is able to do. And it is a common misunderstanding by lots of chronograph users.

quote:

A reloader with a chronograph has a lot more data at his hands to make informed decisions than one using any other method, especially one using the old discredited "case head expansion" method ...

Whoever got this improper notion into boltman's head was simply incorrect and headed him down the wrong trail.

quote:

Anyone who's ever taken a college instrumental analysis class will recognize how that method has no functional basis in science.

Here again boltman has somehow gotten bad information. Nothing could be simpler than measuring metals change dimensionally as they respond to the Effects of Pressure. Granted, only a capable Measuring device should be used or the data is worthless. Verifying Mechanical Dimensions is the entire basis for Manufacturing Mechanical Designs. Nothing tricky or difficult about it because it is done EVERYDAY by people who may only have a High School education.

As a simple example, does anyone actually believe Bullets are not "measured" to see if they meet the Dimensional Specifications while they are being produced?

I am aware there is some Incorrect Information floating around about how to actually measure CHE & PRE. And if that info is followed, I do agree the results are bad, as boltman has said. So in that reguard I do agree with boltman.

If however the Instructions for Measuring CHE & PRE found in that link are followed, the results are the same as they have been for well over 100 years - excellent. It is a simple Comparison of Case Expansion at two different locations on the Case.

Granted there are a few minor "tricks" to ensuring the accuracy, but if the above Instructions are followed, then anyone can have access to the very best Pressure Indicators in existance - CHE & PRE.

Hey boltman, Try following those Instructions and you will quickly realize how simple and accurate CHE & PRE happen to be. Best of luck to you.

Fantastic original post, I must admit I didn't read all of the rest of the posts, although I read some. I couldn't agree with you more and this type of information gathering makes my fellow shooters shake their heads when the shoot through my chronograph. They say that load should be going 200 fps faster. They do not take into account the test gun had a 26 inch barrel what the temp and altitude was and every different firearm will spit that bullet out at a different speed using the same load.
My buddy and I were comparing 3006 loads before hunting season and I know what my load did when he shot my load in his firearm it was 150 fps faster than out of mine with same barrel length. This was also visa versa when I shot his load his load was slower in my rifle. Go figure. You just need to shoot and gather as much info as possible and this will make you a better reloader.

quote:

Wouldn't that number still be based on 'their rifle/primer/brass/barrel' and not indicative of how our setups would perform?

Exactly! Well, since you used the term "indicative", I suppose, strictly speaking, the reloading manual publisher's results can be considered "broadly indicative", but their results are certainly NOT exact proof of anything, except how those guys' rifle(s) may have performed........

quote:

Is it based on the velocity that they observed when the pressure gauge said 'enough'?

Well, maybe. But if so it is erroneous thinking. A given peak pressure will give a certain muzzle velocity ONLY IN THAT SPECIFIC RIFLE, AND WHEN USING THAT SPECIFIC LOT OF THAT SPECIFIC POWDER!

Many people seem to think that a particular peak pressure will drive a given bullet at a specific muzzle velocity, regardless of what powder is used! That is nonsense! Let's look at some extreme examples:

You can load a 180-grain bullet into a .30/'06 case with the precise amount of Bullseye pistol powder it takes to produce a peak pressure of 50,000 PSI. Now, the "standard" MV of a 180-grain factory 180-grain load is around 2700 FPS at a "standard" pressure of somewhere in the region of 50,000 PSI. Do you think the Bullseye load at 50 KPSI will give that bullet 2700 FPS? In actuality, it would probably take enough Bullseye to blow up the gun to come even close to developing 2700 FPS with that case and bullet. OTOH, a much larger charge of a very slow powder may be capable of driving that same bullet from that same case and barrel at velocities greater than 2700 FPS with pressures quite below 50,000 PSI. Trying to correlate pressures with velocities between loads using different powders is a drill in futility....

quote:

Originally posted by Hot Core:

If however the Instructions for Measuring CHE & PRE found in that link are followed, the results are the same as they have been for well over 100 years - excellent. It is a simple Comparison of Case Expansion at two different locations on the Case.

Granted there are a few minor "tricks" to ensuring the accuracy, but if the above Instructions are followed, then anyone can have access to the very best Pressure Indicators in existance - CHE & PRE.

Hey boltman, Try following those Instructions and you will quickly realize how simple and accurate CHE & PRE happen to be. Best of luck to you.

Sorry Hot Core, the science behind the CHE method is bullshit, it just doesn't hold up. The problem with the CHE method is that there isn't a reference standard to compare the brass expansion with and without a standard the expansion readings are meaningless. One lot of brass doesn't expand at the same rate as another. The CHE method is just a poor attempt at replicating the copper crusher method of pressure measurement that used to be done in ballistics labs before the advent of more accurate systems. However, the BIG difference is that each lot of copper crushers were calibrated to known pressures and your brass is not. Also, brass is too hard a material to give reliable expansion data, hence the reason the labs used copper.

As for the guy laughing about the "college instrumental analysis class", it's the class where they teach you how laboratory instruments actually work. You generally don't take it if you're in the basketweaving curriculum. What you'd take away from it is that no lab instrument measures anything directly, virtually everything is measured by comparing the results to a known reference scale. That's the reason the CHE method of measuring pressure isn't based upon science, there's no reference standard. Think about it this way. How do astronomers measure the mass of the sun? They obviously can't put it on a balance, so they can't measure it directly. They can, however, make a good approximation by measuring how light is bent when it passes by the sun and calculate it's mass based upon the known effects of gravity upon light. From this they can calculate it's mass and be reasonably accurate although it's certainly not perfect. Using a chronograph when reloading is no different. Take the good old 30-06, there's plenty of reloading data out there done in a ballistics lab to tell us the relationship of pressure/velocity with a 150 gr bullet using X powder. You can plot this information on a sheet of graph paper and there's your reference standard, it's a known, professionally done relationship of pressure/velocity curve in that caliber. Are there variables with your rifle and load? Certainly. Is the relationship between pressure/velocity linear? Certainly not and I'm not advocating using this to try and eek the last fps out of your rifle, but what you have is known good data that you can compare with your results. BUT, it's an approximation, it's not a direct measurement of pressure. However, it's better than ANYTHING else we have available to us unless you want to spring for one of the strain gauge setups like the oehler M43. MORE ACCURATE DATA ABOUT WHAT YOUR LOAD IS DOING IS GOOD. Reloading in ignorance is not a good thing and reloading based upon data that you think is good but really isn't (CHE) is even worse.

What, in practical application, is the most important thing you can find out about your load with a chronograph? It's during that time when you're trying to work up to that max book load and three grains below max you reach that highlighted velocity in the book indicating their fastest load. You know right there that you're most likely operating near max pressure because you don't get anything for free and your rifle isn't the magic 30-06 that's going to give you 3200 fps out of that 150 gr. bullet. You wouldn't have had that information without the chronograph and it enables you to throttle back and hopefully keep a few more of your body parts intact. It's a testament to how overbuilt most rifles are that so few people get hurt reloading. There's so much junk science going around that it's a miracle we all haven't blown ourselves up.

Well, one think I did learn whilst I was taking remedial basket weaving and clay modeling 202, was that the bullet folks spend a lot of money compiling their books and have an actual liability to publish as near factual information as possible. I further learned that their information is probably more consistantly right than what I can glean from a cyberspace self annointed hot property that has taken a COLLEGE INSTRUMENTAL ANALYSIS CLASS.
Tell me something: You have a cartridge with which you have never worked. Nor anything similar. You have the cartridge, your Chrony, and an array of powders. How do you determine what your first choice of powders will be and what will be your beginning load? If you saym "historical knowledge" (ie Pawleys), you are going right back to knowlege gained from the load books which you say are worthless.
If you have read the various descenting post, everyone that doesn't agree says that a Chrony is a good addition to a reloaders arsenal but that it does not replace the books.
And don't forget the ONLY absolute you will find in any of the reloading data. "Every rifle is a law unto itself and generalizations should be made with circumspection". To explain that to you, it means every rifle is different and what is max in yours might not be in mine. And it sez words to that effect in every reloading book published.

quote:

Originally posted by stillbeeman:
If you have read the various descenting post, everyone that doesn't agree says that a Chrony is a good addition to a reloaders arsenal but that it does not replace the books.

Obviously reading comprehension isn't your strong point either. Read my posts, no where did I say the books are worthless, take them with a grain of salt yes, but worthless no. There's good and useful data in the manuals but it needs to be used and applied in an intelligent manner. I'm not trying to offer you any reloading information, that's not my job, I don't get paid anything for it, and quite frankly I couldn't give a shit less whether you know anything about it or not. I'm, quite simply, explaining how laboratory equipment works, why some methods of estimating pressure are invalid, and why a chronograph can be useful when working up loads. If you don't like reading it then don't read the post. Better yet, hunt down a local mechanical engineer and have him explain to you basic physics and how stress and strain analysis is done. Geez, it's not like it's a secret.

boltman

Same on you for questionning Hot Sh$$ I mean Hot Core.

Aren't you aware that he is the suppository of all knowledge concerning reloading???? I'm anxious to see what the answer will be to your post.

Thanks for your post and the information contained it was great educational stuff.

quote:

Originally posted by the totally incorrect boltman:
The problem with the CHE method is that there isn't a reference standard to compare the brass expansion with and without a standard the expansion readings are meaningless.

Obviously you did not read the Link, nor have you ever attempted to use the very best Pressure Indication Method ever developed for Reloading.

If any of you Beginners ever have a chance to read through:
1. Any of the old Load Manuals.
2. Books by Bob Hagel.
3. Books by Ken Waters.
you will find that both CHE and PRE have been used by every one of the Powder and Bullet manufacturers as well as the Reloading Pioneers who went befor us. It worked great then and still works great today.

quote:

One lot of brass doesn't expand at the same rate as another.

boltman is correct, which points out a major benefit of both CHE & PRE. Since the readings are taken directly from the Case, if it is weaker or stronger, you have the ability to adjust your Load for that specific Lot. No other Method available to Reloaders allows you to take the Lot Strength of Cases into consideration.

quote:

The CHE method is just a poor attempt at replicating the copper crusher method of pressure measurement

This is so far WRONG that it appears boltman has gleened his reloading knowledge from spudman. No, CHE has absolutely nothing to do with a Copper Crusher. Pitiful!

quote:

How do astronomers measure the mass of the sun?

I'm not sure howthis has anything to do with Reloading. Perhaps tater-tot could enlighten us.

quote:

...one of the strain gauge setups like the oehler M43.

Glad boltman brought that up. If any of you still think a HSGS is useful for anything outside a "Certified Lab", you can go this Link and see what the esteemed Dr. Oehler has to say concerning what they are good for.

How `bout it tater-tot, surely you know more than Dr. Oehler!

quote:

There's so much junk science going around that it's a miracle we all haven't blown ourselves up.

I agree with boltman that it is a miracle he hasn't blown himself up.

/

And once again, we are blessed with a long series of tempests sized to fit a tea pot... i wonder if AlGore would attribute this to glo-bull warming??

quote:

Originally posted by Hot Core:
.....Instructions for Measuring CHE & PRE....

Thanks for that, Hot Core. I now have your post saved in my Loading Files.

ALF,

I pretty much agree with your dissertation. Still, for the average reloaders purposes, I believe you still forgot the issue of your data applying only the gun that you are testing. The next gun off the line will require it's own set of data to identify it's trends.

I am also curious how many shots it takes to confirm that the velocities are climbing from the trend? Couldn't we assume that by the time you identify the trend, you have already fired numerous loads that are considerably higher than safe pressure, at an unnecessary risk?

I'm not trying to flame you, ... just asking a few questions.