I was digging through all my files on the 300 WSM and came across two versions of Ramshot reloading data.

I noticed what I thought to be a large variation in regards to the 165 gr. bullets using the Ramshot Hunter powder.

For all you old timers out there or those with a library of old manuals, how much fluctuation do you see in new cartridges from the new data to the well-established data?

For the sake of comparison, here is the old vs. new data I have from Ramshot.

Notice in this example that there is a 3.0 grain difference between the maximum loads for the SBT:

Old (unknown manual version)


New - Version 4.2.2

[IMG]

Thanks for your input!

-Michael

A lot of the variation that you see in new vs old manuals is that they actually pressure test the new ones.
That doesn't however apply here because the obviously pressure tested both sets of data here. I guess that it would have to be due to either a variation in the powder itself, a different pressure barrel, or a different method of testing pressures...............................DJ

Part lot to lot difference in density, and probably part different testing gear. Always rely the most on pressure tested data in the most recent manual, as it's the most likely to have been tested on the most up to date electronic equipment and, thus, is the most likely to be accurate.
------------------------------------------------
"Serious rifles have two barrels, everything else just burns gunpowder."

You know what's funny about all this?

Of the three variables:
-weight
-pressure
-velocity

One of them remains constant despite changes in rifle, lot #, or instrumentation.

The VELOCITY remains constant.

Hmmmm... If I were a powder company trying to sell propellant, the last thing I would want my data to show would be a loss in velocity.

Regardless, after 14 years of handloading, I am slowly coming to the general conclusion that VELOCITY is the best indicator of maximum pressure. Charge weights are becoming less important to me, although I continue to keep a careful eye on recommended maximums.

It has been said on here many times before that there seems to be a closer relationship between pressure/velocity rather than pressure/charge weight.

Just my two cents.

quote:

Originally posted by Kenati:
...VELOCITY is the best indicator of maximum pressure. ...

Actually, Velocity tells NOTHING about Pressure.

Best of luck to you.

The velocities remain similar but there is a change of a few KPSI in the loads. Not much but it is there. The pressures seem to be higher along with the increase in charge. This could be only a reflection of the change in powder lot used.
I`ve read but don`t remember where the industry std for variation in burn rate of canister powders is +/- 5% and is the reason for the manuals warnings to start 10% below max and work up.
Then again it could be nothing more then normal variation in the results of the accuracy of the lab equipment/tech that was used to compile it.

quote:

Actually, Velocity tells NOTHING about Pressure.

HC actually velocity is related to time under pressure and as long as the SAME components are used the burn "should" be close enought to give a fairly close vel/psi. I agree a different lot of powder, or other component or rifle will change things slightly but, one should be as close to being in the ball park as with pressure ring measuring as long as all components are as listed.
JMO as you know....

I really don't want to start a contest, especially given the number of recent and ongoing posts on this topic.

However, Jagter asked the same question as I wanted to, so I'll just quote him here from the "Signs of pressure?" post:

"Velocity is not dependent on the amount of pressure applied to the bullet when launched out of a rifle?"

--A side note regarding my load developement procedures--

I load at the range using:
-Wilson inline hand dies
-Sinclair primer seater
-Harrel powder measure (with pre-recorded weight settings)
-Blade micrometer
-Log book

1. When nearing maximum loads in the book, I fire 5 loads of the same charge with a single case. (Easy to do with the portable BR equipment)

2. I measure and record case head expansion and note any differences in primer seating. The usual pressure signs are noted as well (sticky bolt, flattened primers, etc.)

3. Velocity to charge weight increases are noted as well. I become very cautious when the trend starts to veer from the more typical linear relationship.

4. I buy everything in bulk to eliminate lot to lot inconsistency. Powder, for example, is bought in 3 to 8 pound quantities, the same lot number is confirmed, and then I combine them into larger sealed containers. I spend a lot of time working up individual loads, so the last thing I want to do is waste my time and components because of a change in powder, primer, or brass lot #.

Hey Kenati, I've no desire to argue about it either - especially since I'm right!
-----

It looks like you have an excellent Reloading procedure. And if you want to believe you know what the Pressure is by looking at Velocity, it is fine by me. But, it just isn't possible, way too many variables.

You may not be aware that I'm also not a fan of folks wasting money on a HSGS(aka Fool's Gold). And even Dr. Oehler mentions somewhere within this thread that his M43 can be off by 8k-psi.

The only thing a Chronograph tells is Velocity. However there is a hard-core group of folks who have wanted to believe for many years they could cipher Pressure from Velocity. It just isn't possible. Reality is tough on old Full-of-Beans stories.

Hey Ol' Joe, I do agree that it takes Pressure in the Firearm to create the Velocity. But it is not possible to make rational Pressure Conclusions based on the Velocity. It just doesn't work that way.

Best of luck to you all.

/

quote:

Originally posted by Hot Core:

Hey Ol' Joe, I do agree that it takes Pressure in the Firearm to create the Velocity. But it is not possible to make rational Pressure Conclusions based on the Velocity. It just doesn't work that way.

Best of luck to you all.

While you can't make a direct relarionship of higher vel. to higher pressures, there are few free lunches. It's pretty diff. to get higher vel. w/o higher pressure within a given powder burn rate.

There are some of us that consider any loading manual that includes a WSM cartridge could hardly be old by any standard.

Old loading manuals vs. new manuals often go both ways ...some actually use lower loading maxs than the newer ones. But the idea that powders and the consistency of powder are much improved I tend to trust the newest ones and only use the old ones for reference. Using a chronograph....something that few could afford in the "old days" really tells the tale.

May I suggest that the differences in pressure shown may in part be because different test equipment operators were doing the testing?

Anyone who has experience doing pressure/load testing is likely aware that different operators using the same equipment come up with rather widely different results.

Phil Sharpe reportedly once loaded a large batch of ammo and sent it to two ammunition manufacturers and the H.P. White Labs for pressure testing. The highest readings were almost double the lowest ones, with the third set almost in the middle of that range IIRC. Ten years later he reportedly sent the remainder of the same batch of ammo to the same three labs, and got the same spread in readings back.

The really interesting part is that each lab's tests were very consistent. The one which reported the highest readings the first time did so again the second time, ditto the lowest and middle sets of readings.

quote:

Originally posted by Alberta Canuck:
May I suggest that the differences in pressure shown may in part be because different test equipment operators were doing the testing?...

...Ten years later he reportedly sent the remainder of the same batch of ammo to the same three labs, and got the same spread in readings back.

The really interesting part is that each lab's tests were very consistent. The one which reported the highest readings the first time did so again the second time, ditto the lowest and middle sets of readings.

Now THAT is very interesting! Thanks for sharing.

As a side note, it makes me wonder about the blood work we send off from the clinic to a big contracted reference laboratory. I know their methods are "standardized", but what if we cross referenced them with another lab just for argument's sake? Hmmmm... I might be writing fewer prescriptions for high cholesterol meds! (Or maybe more!) At any rate, this is illustrative of variation in measurement, rather than variation in the absolute.

quote:

Originally posted by Kenati:
At any rate, this is illustrative of variation in measurement, rather than variation in the absolute.

EXACTAMUNDO, SKOOKUM KENATI!!

Might be one of the reasons Hot Core and I frequently find ourselves agreeing about questionable relationships between different aspects of shooting....and why we both tend to look closely at such experiments as we often see printed in publications such as Precision Shooting, before buying them as "whole cloth".

An awfully lot of experiments in this hobby are reported in a definitive manner, without the cross-correlation of either measurements, OR tester ability/motivation.

That's not a bad thing...not reporting the results of individual tests would be worse. But, it does mean a guy should keep his thinking cap on......

Could this combination possibly be the solution?
Check velocity and pressure all at once with 'The New CED M2 Chronograph' combined with the 'PressureTrace II (Available Soon)'.

Sounds great!

quote:

Originally posted by Jagter:
Could this combination possibly be the solution?
Check velocity and pressure all at once with 'The New CED M2 Chronograph' combined with the 'PressureTrace II (Available Soon)'.

Sounds great!

I'm sure many shooters and handloaders would find it useful. However, reading the hype about it raises a LOT of questions in my mind.

1. They talk about not using 100 years old ballistic formulae. I think they mean their new formulae are better, but another way to read that is that they are using new formulae which don't have the benefits of 100 years of use/testing behind them. Or that they believe the laws of physics have changed?

All computers which calculate anything need algorithms (formulae) to do their work. And from those formulae comes the expression "Garbage in - Garbage out". All a formula does is state in math symbols a relationship with the formula developer "BELIEVES" is valid. But a lot of people believe UFOs are alien space ships too......

2. I note that their validation testing comparison was done against HP White supplied data. H.P. White is one good competent lab, but just one. Who says its data is not subject to individual operator variances and would be the same as some other lab's finding? It is possible to "cherry-pick" supportive tests, though I hope CED wouldn't do that.

3. Does everyone reading their ad also understand that no one can get reliable data unless they go through a rather long learning & training curve as to how to set up their individual machine and environment so that the machine(s) work(s) best, AND learn how to best operate the tests themselves?

Then they need to learn and perform sufficient personal discipline so that they make sure those learned requirements are consistenly applied. Otherwise every separate test they perform will to some extent result in data comparing apples to oranges.

4. They note that one predictive formulae predicted a certain pressure but their testing machine showed MUCH more pressure than predicted. So which was wrong? The prediction, the machine, both?

There are a lot of other aspects to think about, but those are a few which spring out at me.

Surely, even inconsistent results (and to that degree at least some of them are inaccurate results) are better than no testing., but it may also lead a person astray once in a while...hopefully not enough astray to get hurt, but maybe is something else one should think about before totally relying on such a machine.

What I find interesting is that the max loads only changed (downward) 1 grain; however, the starting loads changed (downward) from roughly 68grs to 63grs, which is about 5 grain, thereby increasing the low to high spread from about 3grs to 7grains. Correspondingly, velocity changed from 3000fps to 2800fps for the starting loads.

This looks as though over time the manufacturer has extended the lower limits of the loading envelope. I would bet they determined the original data was a tad too hot, although the psi is reported as being higher in the latest data. Kudude

Alberta Canuck & kudude,

True what you're saying about these new gadgets!

If I were in the USA I would have asked these guys to come and demonstrate these things or tried to get to them personally.

I don't see where they're situated in the US on their website, but can't you experienced guys there locally try to find more out about the equipment, please?

If it works correctly it would really be something great for all reloaders.

Sorry, here they are:

quote:

Our physical place of business is 1343 Navajo Dr., Cottonwood, AZ 86326 at the foothills of Mingus Mountain, below the ghost town of Jerome, and on the opposite side of the Verde River Valley from Sedona.

Don't know where that is!

Jagter -

If you have a map of Arizona, you can see I-17 heading north from Phoenix to Flagstaff. About 2/3 or 3/4 of the way from Phoenix to Flagstaff, just off to the NW of I-17 you will see the town of Sedona. Mingus Mountain rises just west of Sedona on the west side of the Verde River. Jerome is an old mining town more built "into" than "onto" the side of Mingus Mountain, about half way up. If a person follows the narrow twisiting highway west over the top of Mingus Mountain and down the other side, he will eventually come into Prescott, Arizona, just a bit north of the airpark where the Ruger pistol factory is located.

It is beautiful country, full of javelina, deer and antelope (which, depends on elevation). Also has a fair bit of bird game and the occasional elk or bear thereabouts. If a person doesn't need quick access to medical care, it is a great place to live. Cooler than the desert just a few miles south of it, nice clear air, and just a few hundred thousand too damned many California tourists who come there each year to get away from Kalifornia, but still demand that everything be just like it is in California...go figger.

Nice as it is, if I wanted to live in the area, I'd follow the Verde River SE past I-17 for 25 miles or so out into the desert, where a guy can just pick up his rifle and wander all day long in the high chapparal (SP?), picking up the odd coyote, rabbit, big desert mule deer, maybe even a mountain lion if he has both luck, a mule, and good dogs. 'Course you have to be careful about the 'Coon-tails and Green Mojaves out there too, but it's worth it.

Alberta Canuck,

Thanks for your beautiful description of the country thereabouts - I can almost see it if I close my eyes!

Yet I'm in the far off RSA and no chance soon or whenever that I will get in Arizona.

How far is it away from Oregon where you are?

That's why I've asked if you or kudude from Florida - sounds much like California in your description - can't find out more about it and let all reloaders on AR know about the merits of it.

Anybody else who could help with first hand info?

Jagter -

That particular part of Arizona is not easy to reach from here, there is no very straight route to it by highway, so, by road, it is about 1,250 miles from my current house here in Oregon. Of course it is quite a bit shorter trip (and straighter) by light aircraft.

I was born and spent my early childhood in the Arizona desert a bit south of the Mogollan (sp) Rim, then moved back to Arizona when I was 44 years old and spent 9 more years there. One of my best friends was a lion guide in that area we are speaking of, and I used to travel with him some fair bit. Another close friend had a cabin about 40 air-miles north of there and I used to stay at this cabin almost every deer season...and of course I hung around the gun-makers,gunsmiths,and wolfePublishing company in Prescott too.

As I used to spend a lot of my time and money wondering the American "Outback" I know many, many forestry roads and other byways all over the West...in fact I daresay I might be able to drive from here to Jerome, Arizona with less than 100 miles on pavement, if I had to. Most of California is much different than Arizona, tending to be more lush, but SE California is very much like the Jerome area, so long as you stay up out of the low desert parts of California. If I had to pick a part of California to compare Jerome with, I'd say maybe somewhat more like Bishop, California.

Anyway, I am sure the machine is a good effort...their chronos are quite good for their low price. I think it would be useful and probably worth every penny of its cost. I just like to warn folks new to this kind of testing and equipment that there is nothing out there reasonably priced for an individual shooter which is "THE" answer. Good, affordable tools will give useful information to their users, but they are all dependent on the manufacturers' understandings of the problems to be answered, and their interpretations of what the requisite, relevant physics (and their pertinent descriptions) are.

And all of them will have weaknesses.

Methods & Materials:
Today, I shot the 168 gr. Hornady A-Max using the Ramshot Hunter powder. This is my "practice" bullet used in the off season.

After chamfering, flash hole and primer pocket uniforming, I decided the new Norma brass fed and fit well enough to skip the body die and just neck sized ONLY using the inline hand dies.

I slowly worked my way up in 0.5 grain increments.

I now you all love accuracy tests as much as I do, but this was not the purpose of my range day. (Pre-storm with 20 mph gusts). However, I will say that the loads discussed below were 0.75" or below at 100 yards (I was using 1" grid target and kept all shots well within a single box)

Results:
Using the SAME three pieces of Norma brass in the same order for each string.

1. New brass
2. Once-fired - neck only
3. Twice-fired brass - neck only



Discussion:
Being that these are only practice rounds I did not try to push the limits of pressure and velocity. Also, I was shooting for a specific velocity with regards to a predetermined bullet drop and drift in mind. As planned, 3,100 fps in the high B.C. A-Max bullet corresponds nicely with my faster but less aerodynamic (and much more expen$ive) hunting bullet.

As you can see above String #5 using new UNIFIRED brass had the greatest Extreme Spread (ES = 83.8), Mean Absolute Deviation (MAD = 28.6) and Coefficient of Variation (CV = 0.9%).

String #6 & #7 had lower MAD = 6.6 fps and 9.4 fps, respectively. The CV was 4.5 and 3 times lower than the new brass, respectively.

[Note: This all has very low Power because the sample size (n=9) is extremely low. That is reason I used the Mean Absolute Deviation (MAD) instead of Standard Deviation... it works better with a small sample size.]

Because I used the same three pieces of brass in the same order each time, I could not see a correlation between one particular case being faster than another one. Subjectively, velocity differences appear to be Normal variation.

In terms of case observations, at 70 grains and a little over 3,100 fps averge for the three strings, I noted an increase in both a) bolt lift and b) the faint line of fresh brass flow on the case head overlying the ejector slot. Primers were not flattened, crattered, or too easy to remove. Using the $inclair hand priming tool, the last batch of primers felt like they seated identical to the new brass.

Conclusion:
Let's be serious...
Because all of this is based on a measly 9 rounds, it's really just a bunch of B.S. watered down with steaming hot piss.


But if I were to naively draw any conclusions I'd say the following:

1) Fireformed brass has 3-5 times less velocity variation than new unfired brass.

2) 70 gr. of Hunter powder for the 168 A-Max in my particular 300 WSM is near maximum. This corresponds very well with the NEW data version 4.2.2, as originally posted. Good job, Ramshot.

3) I will be much happier if I quit typing this shit to go drink a beer, eat sausage off the grill, and tell tall tales of wild women and guns with my buddies!

I apologize if I wasted anyone's time.

G'night everyone!

quote:

Originally posted by Kenati:
...In terms of case observations, at 70 grains and a little over 3,100 fps averge for the three strings, I noted an increase in both a) bolt lift and b) the faint line of fresh brass flow on the case head overlying the ejector slot. ...the last batch of primers felt like they seated identical to the new brass.

Excellent Pressure observations that actually tell you something worth knowing - unlike the Velocity.

"More Power to you!" - Briscoe Darling