Where can I find load data for the heavy Woodleigh bullets, like the .366 cal 320gr bullets and the .375 cal 350 gr bullets? With the lighter stuff you can look at data for similar weighted bullets, but not with the big stuff. Checked their website, and didn't find anything.

Steve

Best sources are from someone you trust who has loaded it. I cannot think of any published data offhand. What are you loading for perhaps I can find some data for, or at least run a simulation to give you an idea.

ASS_CLOWN

9.3x62 and .375 H&H. Thinking about the 320 gr .366 bullets and the 350 gr .375 bullets.

E-MAIL ME <>I HAVE SOME DATA I CAN FORWARD TO YOU... MADDOG

skl1,



For the 9.3X63 Mauser



320gr Woodleigh PP to the cannelure.

22" barrel

CCI200 primer



H414 powder

100% load density -> 54.8 grains -> 1854 fps -> 43,063 psi

105% load density -> 57.5 grains -> 1911 fps -> 45,169 psi

110% load density -> 60.3 grains -> 1972 fps -> 47,878 psi



IMR4064 powder

100% load density -> 52.7 grains -> 2089 fps -> 58,762 psi

105% load density -> 55.4 grains -> 2178 fps -> 61,148 psi

110% load density -> 60.3 grains -> 2251 fps -> 64,082 psi

< !--color-->



The last two loads for IMR4064 exceed the pressure limits of the 9.3X63 Mauser cartridge (I believe it is 60 ksi).



Good luck.



If I get some more time later I will work out the 375 H&H for you with the 350 grain Woodleigh.



ASS_CLOWN

Contact Ray Atkinson! I have used re-15 with the 320 Woodleigh soft point in my 9.3 x 62 with no problems. The data came from him and it was perfectly safe in my rifle, Mod 98 Mauser. I wasn't able to quickly find the load but Ray will have it.

Thanks, all.

Steve

skl1,

The promised 375 H&H data.

350 grain Woodleigh loaded to cannelure
Federal 215 primer
24" barrel

IMR4895 (H4895)
85% load density -> 61.9 grains -> 2239 fps -> 60,031 psi
90% load density -> 65.5 grains -> 2397 fps -> 66,271 psi -> exceeds MAX
95% load density -> 69.2 grains -> 2543 fps -> 73,266 psi -> exceeds MAX < !--color-->

IMR4064
85% load density -> 61.4 grains -> 2158 fps -> 57,572 psi
90% load density -> 65.1 grains -> 2293 fps -> 61,018 psi
95% load density -> 68.7 grains -> 2446 fps -> 68,277 psi -> exceeds MAX
< !--color-->

H414
95% load density -> 71.3 grains -> 2236 fps -> 53,726 psi
100% load density -> 75.0 grains -> 2427 fps -> 59,894 psi
105% load density -> 78.8 grains -> 2670 fps -> 70,927 psi -> exceeds MAX
< !--color-->

SAAMI maximum pressure is specified at 62,000 psi.

Looks like H414 is you best choice for maximum velocity. 4831 may be a good choice as well. If I get time later I may simulate that powder for you also.

ASS_CLOWN

I found the data for the 320 Woodleigh in the 9.3 x 62.
Try 56.5 gr of Re 15. It has shot 1/2 inch in a Sako and just over an inch in a Mod 98 with 26 in barrel. Velocity is probably in the 2350-2400 fps area.

Janus,

Have you actually chronographed that load? I suspect that it is a safe load pressurewise, but the velocity numbers you cite seem mighty high, even for a 26" tube.

ASS_CLOWN

ASS ClOWN,
Your are way off on the 9.3x62, not even close on your velocities...Must be a mistake somewhere...I have chronograph data going back many years for the 9.3x62 and I get just a hell of lot more velocity that stuff you printed...and all the books show much more velocity...

Better go back to the drawing board on that one...

9.3x62....Fed 210...Norma brass....26" barrel...10 shot average with high and low taken out:


H414:
230 GS HV.... 66grs. 2790 FPS
250 Nos. Bal. Tip....62 grs. 2650 FPS
286 Nos. Partition...56 grs. 2411 FPS

RL-15 same components:
56.5 grs. 320 gr. Woodleigh 2380 FPS
58. grs 300 swift, 2450 FPS
59 grs 286 Nosler part 2560 FPS
58 grs. 286 nosler Part. 2520 FPS

I have a multitude of tested loads but these are about the best...The Swift manual has some good loads mentioned..

375 H&H:
The load I used on Buffalo last year in Tanzania was 66 grs. of RL-15 with the 350 gr. Woodleigh RN..It seems to be a mild load at 2356 FPS, I intend to work on this load and max it out for this year and the PP version if I take the 375..

Ray,

Not so sure that the velocities are off that much. My analysis is from a 22" barrel and you say you are using a 26" tube. That alone may explain 100 to 150 fps.

The 375H&H data is calculated with a 24" tube and the numbers are pretty close to yours.

You know every rifle is it's own beast. So every rifle will read a little different, as will practically every chronograph. I suspect your pressures may not be as low as you think they are on some of your loads though.

ASS_CLOWN

Ray

Quote:

---

RL-15 same components:
56.5 grs. 320 gr. Woodleigh 2380 FPS

---

I ran this load through the software and corrected it came back within 10 fps, when the barrel length was adjusted to 26", and an adjustment was made to provided for a "hot" lot of Rel 15. However, the pressure was a tad high @ 63,792 psi < !--color--> !

I wouldn't go any higher with that load if I were you.

ASS_CLOWN

Ray,

For this load:

Quote:

---

375 H&H:
The load I used on Buffalo last year in Tanzania was 66 grs. of RL-15 with the 350 gr. Woodleigh RN..It seems to be a mild load at 2356 FPS,

---

My software predicts, with a 26" barrel a muzzle velocity of 2369 fps @ 64,137 psi < !--color-->

You like to load them hot don't you!

ASS_CLOWN

Don't put too much faith in your reloading software, I'd spend my time testing the loads myself. In my rifle I load 59 gr RL15 with the 286 Nosler and it only goes 2415 fps out of a CZ 23 1/2 in. barrel. I'm sure I could load 60 grains very safely in my gun, and can't imagine the 56.5 320 Woodleith load would be too hot-in my rifle, maybe not yours. I've seen tests where they used the computer predicted velocity and compared it to an actual in some varmint rifles, some would be right on, some would be 200-250 fps off.

jstevens,

No offense, but I have MORE confidence in the calculations than I do in your ability to "read" pressure. The truth is, you WILL only SEE pressure signs after you have yielded (read over-loaded) the case! The Mauser case head takes ~ 70,000 psi internal pressure to yield the case head; therefore, providing the visible "pressure" signs many refer to. So until your load exceeds ~ 70,000 psi you won't see case head expansion, or blown primers, or leaking primers, or any of the other so-called signs of excessive pressure.

By the way, your loads calculate out to around 61000+ psi. And an increase of 12% in bullet mass WILL significantly increase the pressure. So if your current load is already pushing the pressure limits, which it is, your will really be pushing the pressure limits by increasing bullet weight.

ASS_CLOWN

Ass Clown
No! I did not chronograph the load but I knew that Ray had and it had worked with no apparent problem in my 26" 9.3 x 62 Mod 98.

Ass Clown,
To start with were not that close on velocity FPS inasmuch as you are getting 1972 FPS, out of a 22" barrel, and I'm getting about 2350 with my 26" barrel a difference of 378 FPS not your posted 100 to 150 FPS...

Also your figures are BS, the book max for H414 is 71 grs. and your 7.8 grs. over book max with the 375 and H414..check out the Hogdens manual..and with our max load it is near impossible to get a 350 gr. bullet in the case and if you do it will push out before morning Apparantly your getting that information from a book and not from hands on loading experience with the 9.3x62...

I have always tried to be a gentleman and not get in on your usual deserved bashings, but sometimes you really push the string with your off the wall posts...

And your pressure figures are all out of porportion..Just some more of you usual BS, that keeps you in deep do-do...

assclown---I noticed your reference to softwear by which you calculated expected pressure etc. I am interested to know more about that if you dont mind telling me?

Ass Clown,
Look at a max load of 70 to 72 grs of RL-15 in the 375 H&H as listed in various reloading manuals for a 300 gr. bullet, then tell me that 66 grs. is too hot for 50 more grs. of bullet. It just is not operating at your pressures..then check all the loading books for the 300 gr. Swift bullet in the 9.3 and then again tell me I am too hot..Then you list a load near 8 grs. over max as OK!! C'mon man give me a break...If the name fits, wear it..but at any rate thinks for the post as I did go and do some research on my loads and that's always good, but I think that I will stay with them other than I found a better powder for the 350 bullet in the 375 and maybe the 9.3x62 with the 320 gr. bullet..that being H4895, we will see.., so perhaps some good came out of your posts...

Hodgdon has fresh data for this chambering. They include data for 270, 286, and 300 gn bullets. For a given powder, you could plot charge and fps on paper vs. bullet weight and then extrapolate to 320 gn. This is hardly a foolproof method, of course. If you try it, start the charge low, and use a chronograph to be sure the fps isn't getting beyond predictions.

Hodgdon's fps will look low, but don't think ill of Atkinson's fps claims. Hodgdon is keeping to CIP's pressure limit of about 49,000 as indicated with copper crushers. Ray is loading his up; his rifle action is probably also chambered in far hotter cartridges, indicating there is some margin. CIP, like SAAMI, is playing it safe given the age (steels) of some the rifles chambered for it. I have no idea at what pressure your action was proofed; you too may wish to be as conservative as Hodgdon.

One can also estimate performance using QuickLOAD. The software is better at predicting performance than it is at predicting exact charge weights of a particular powder. It's fps numbers agree with Hodgdon's tests. It predicts a bit over 2200 fps from a 24" tube with the 320 gn bullets seated out. Cranking the pressure up to .270 Win levels and using a 26" tube, it predicts about 2400 fps, in line with Ray's results.

Karl

I am looking for load data for the 450 grains bullet in my 416 Rem. Mag. I have been using the 410 grains Woodleigh loaded with 80 grains N150 with great success in Zambia, but so far I haven't been able to find any data for the 450 grains bullet. Any suggestions?

Ray,

Starting at 72 grains and reducing to 66 (6 grain reduction) is only 8%. Increasing the bullet weight from 300 grains to 350 grains (50 grain increase) is 20%! If I NEED to explain to you that your recipe has DRAMATICALLY more pressure than the 72 grain load behind the 300 grain pill, well I was taught if you cannot say anything nice keep your mouth shut!

Sorry, but your loads are HOT! You can use them if you like, but that still doesn't change the fact that your your loads are HOT!

ASS_CLOWN

Ass Clown,
Your confusing the issue with gobbledegoop, it is not a hot load but I have just changed to H4895 and can get in excess of 2450 FPS with a 350 gr. bullet, book max load... according to the Hodgden manual..I didn't realize my old Hod manual had 350 gr. data, but it does.So its a moot question to me now...

Hodgedons max load of H414 was 71 grains, yours was 78.8, so how can you continue your scolding, when you recommended 7.1 grs. over book max?, c'mon, you need to learn how to work that gizmo you depend on, apparantly thats why your figures get such high pressures...

And I did not start at 72 grs., I had no reference for the 350 gr. bullet at the time..so I started at 60 grs. and worked up to 66..I reached my rifles max cut two grs. and reloaded one case 5 times without needing a trim, and velocity is a bit slow...I was satisfied with the load, used it in africa all last year, no problems, but now I have found a better load with more velocity by a good deal..At the time I got the Woodleighs the only load I had was the 66 grs of RL-15. I simply disagree with your figures, or how you got them...

At any rate the H4895 is more accurate, much faster and does not suffer the problems of compaction in the .375 case.

Tommy Igi,

For the .416 Rem I shoot 75 grs. of RL-15 for a tad over 2400 FPS with the 450 gr. Woodleighs..It is one heck of a Buffalo bullet and its accurate in my rifle...

The RN expands to a huge cross section and comes to rest on the off side or will knock a heck of a hole going out...the PP will pass through almost every time unless the angle is too severe...I think I like the PP best.

I talked Geoff Woodleigh into making that bullet and we talked about it many times, he wanted the PP and I the RN, as it ended up he was right on that one as one would expect, after all he is the bullet maker, but the RN is definately best for herd shooting...

I think H4895 might be a great powder but have not tried it in the 416 as yet, but it sure works great in the .375 and is looking good in the 9.3x62...we'll see..

asfd,

Your explanation is mute to me for the simple reason that you cannot perform 6th grade math! [(350-300)/300]*100 = 20%!!!

Sorry buddy but if you cannot do that correctly how can we expect you to handle the much more difficult mathematics involved with exponential expansions.

I also suggest you get some REAL reloading experience i.e. load cartridges fire them over chronograph, etc, and QUIT relying on generalizations on websites and bogus QuickLoad simulations which are typically off by 10% or more!

Ray,

Here is precisely what I posted. 78.8 grains of H414 WILL fit in the case, but IS a OVERLOAD!

Quote:

---

The promised 375 H&H data.

350 grain Woodleigh loaded to cannelure
Federal 215 primer
24" barrel

IMR4895 (H4895)
85% load density -> 61.9 grains -> 2239 fps -> 60,031 psi
90% load density -> 65.5 grains -> 2397 fps -> 66,271 psi -> exceeds MAX
95% load density -> 69.2 grains -> 2543 fps -> 73,266 psi -> exceeds MAX

IMR4064
85% load density -> 61.4 grains -> 2158 fps -> 57,572 psi
90% load density -> 65.1 grains -> 2293 fps -> 61,018 psi
95% load density -> 68.7 grains -> 2446 fps -> 68,277 psi -> exceeds MAX


H414
95% load density -> 71.3 grains -> 2236 fps -> 53,726 psi
100% load density -> 75.0 grains -> 2427 fps -> 59,894 psi
105% load density -> 78.8 grains -> 2670 fps -> 70,927 psi -> exceeds MAX

---

If loaded to 62000 psi / 63000 psi with a 26" tube I think it would be quite easy to hit 2450 fps with a 350 grain pill in the 375 H&H. I think you just like to argue Ray, as you HAVE NO WAY to know what pressure you are at, do you? You WILL NOT see any pressure signs until you exceed ~ 70,000 psi! So if you are running 66 ksi I would expect you to THINK it was hot, even though it is. By the way, I have found Hodgdon's data to be the MOST unreliable data available!

I won't argue this any longer, with you, since that is obviously what you want to do. If you can provide me with OBJECTIVE pressure data, meaning YOU measured it with calibrated strain measuring equipment, off of your rifle, I will continue to discuss this with you Ray. Otherwise, just drop it cause you blowin' smoke.

ASS_CLOWN

OK Clown, you say

Quote:

---

you cannot perform 6th grade math! [(350-300)/300]*100 = 20%

---

Now, I realize you are Einstein's successor, but let me help you here. Go pick up a calculator and punch in the numbers above. 350-300 = 50 and 50/300 is 1/6 which times 100 is 16.7%.

I am truly impressed you can handle "exponential expansions" and all that. It is even more impressive that you have been able to reduce the chemistry of propellants to such simple math. At the nearest engineering college, I looked up some of the papers QuickLOAD's author referenced. It seems even researchers in the field report in their papers that they don't truly understand how this all works. When they attempt predictions, they rely on digital simulations, which at its core is 6th grade math, so maybe I can yet understand it all!

QuickLOAD simulations are indeed not accurate. If you compare it's results to published lab data, you'll find it never gets it right. Of course, real test data from different labs often differs as much. I certainly never put my face behind a breech loaded with QuickLOAD loads.

Still, QL always seems to predict the performance potential of a cartridge, even if it can't tell you which powder and how many grains of it is needed to safely obtain that performance.

Quote:

---

90% load density -> 65.5 grains -> 2397 fps -> 66,271 psi -> exceeds MAX

---

Oooooo, your predictions are truly outstanding! I don't think anyone in the field has faith in more than 2 digits of pressure, let alone the 5 you offer.

So just where did you come up with the above numbers?

As for loading for max, I never try to reach max loads. I use my chronograph and stay well below published fps limits.

Quote:

---

just drop it cause you blowin' smoke

---

Maybe blowing some, I am, but not billowing, as you are.

asdf,

You caught me, I was being a clown, forgive me.

Your premise that I am using QuickLoad is grossly erroneous though.

Quote:

---

I don't think anyone in the field has faith in more than 2 digits of pressure, let alone the 5 you offer.

---

I find this statement immensely interesting! Do you know why no one has faith? Shall I tell you, and in somewhat nauseating detail? The software spews out hundreds, tens and ones because of the nature of it's pressure curve fitment equation. It is simply a mathematical idiosyncracy, that is all (seriously it isn't a conspiracy or anything ).
==================================

I hope this explanation isn't too difficult to follow as it is VERY technical. It will illustrate the reason for the distrust in pressure measurements hinted to by asdf, as well as, explain why pressure estimation methods by "case head" or "pressure ring" expansion are, for the most part, BOGUS!

I will leave out a CONSIDERABLE degree of physics discussion and derivations and provide the end result.

When one is taking pressure readings on a barrel, test or actual rifle, they are using a strain gage (typically either potential or resistance). These gages, as their name implies, measure strain (one by change in milli-volts and the other by change in milli-ohms) specifically Hoop strain . I will spare you all the details of how volts or ohms become inches/mm.

This strain data is then used to perform some calculations to understand the pressure at work in the barrel.

There is a whole discussion I will now skip on the relationship between stress, strain, Young's modulus, Poisson's ratio, etc and skip directly to the end results.

The fundamental equation for the Hoop strain (the metric which we are measuring with the strain gage) at the special case of the OUTSIDE diameter of the barrel is given by:

(1.71 * Pressure * ri^2) / E * (ro^2 - ri^2)

where:
E = Young's modulus (29,600,000 psi for SAE 4140)
ro = outside radius of the barrel
ri = inside radius of the barrel at ro

Before we continue, consider that a VERY GOOD micrometer is only accurate to 0.0001" (That is one ten-thousandths of an inch)

For a typical sporter weight barrel:

ro = 0.575" (1.150" outside diameter)
ri = 0.2565" (chamber diameter of 0.513" or the 375 H&H)
E = 29,600,000 psi

Hoop strain per every 1000 psi of chamber pressure - 0.0000143" ( that has 4 zeros in front of the numbers or one more than 0.0001" the best your BEST micrometers CAN measure )

So looking at some specific examples:

Hoop strain of a sporter weighted 375 H&H magnum @
57,000 psi - 0.000815" (micrometer reading 0.0008)
59,000 psi - 0.000844" (micrometer reading 0.0008)
60,000 psi - 0.000852" (micrometer reading 0.0008)
61,000 psi - 0.000872" (micrometer reading 0.0008)
62,000 psi - 0.000886" (micrometer reading 0.0008)
63,000 psi - 0.000901" (micrometer reading 0.0009)
64,000 psi - 0.000915" (micrometer reading 0.0009)

The best micrometers CANNOT tell the difference between 56,000 psi and 62,000 psi!!! That is the FACTS no BS.

It gets WORSE with a bull barrel and even worse yet with the extremely heavy walled test barrels. This is ONE major reason that reload manuals frequently leave out pressures, they simply cannot accurate determine them with their grotesquely heavy test barrels so it is ommitted for liability reasons!

For a bull barrel with the following dimensions:

ro = 0.625" (1.250" outside diameter)
ri = 0.2365" (chamber diameter of 0.473" or the 22-250 Rem)
E = 29,600,000 psi

Hoop strain per every 1000 psi of chamber pressure - 0.0000096" ( that has 5 zeros in front of the numbers or two more than 0.0001" the best your BEST micrometers can do)

Hoop strain of a Bull Barrelled 22-250 Rem Varmitter @
50,000 psi - 0.000480" (micrometer reading 0.0004)
55,000 psi - 0.000528" (micrometer reading 0.0005)
57,000 psi - 0.000547" (micrometer reading 0.0005)
59,000 psi - 0.000566" (micrometer reading 0.0005)
60,000 psi - 0.000576" (micrometer reading 0.0005)
62,000 psi - 0.000595" (micrometer reading 0.0005)
63,000 psi - 0.000605" (micrometer reading 0.0006)

So in the case of a bull barrelled varmit rig the best micrometers CANNOT tell the difference between 53,000 psi and 62,000 psi!!!

There you go asdf, the clarification / explanation to your statement

Quote:

---

I don't think anyone in the field has faith in more than 2 digits of pressure, let alone the 5 you offer

---

They should not have faith in two, I am afraid.

There are ways to improve the resolution and therefore the accuracy, but they can be dangerous and require special calculations and induce a dramatic reduction in barrel life thus the dangerous part!

By the way, these calculations are valid as long as your barrel is not permanenetly deformed. Barrels don't permanently deform until a just before they EXPLODE, though!

How's that for blowing smoke!

ASS_CLOWN

The old handloading rule of thumb is to take the percentage of increase in bullet weight which is 16 and divide by 2 and decrease the charge by that amount. This comes up with a charge of 72 grains for 300 grains, 66 for 350, amazing that works out to be exactly the two loads we're arguing over. By the way mine sure as hell won't take 72 grains with a 300 grain North Fork,as 72 grains RL15 with a 270 goes 2770 fps. You can be sure that my 9.3x62 loads that only go 2415 fps in my rifle aren't creating 70000 psi, no matter what your software says. It has no means of accounting for seating depth, length of freebore, brand of case, type of bullet used, or any number of other variables. The software will provide accurate starting data, etc. so is useful. Also, I will agree that a mike likely tell the difference between 56000 and 62000, but this isn't going to cause a rifle to disintegrate. The other problem with current strain gauges is you have to guess what pressure is with a factory load of unknown pressure and calibrate from it, so this doesn't excite me much. I've loaded since 13 years of age, I'm 47, and blew a primer once in who knows how many thousands of rounds.

jstevens,

For the record I never said the 56 grain Rel 15 load in the 9.3X62 was 70 ksi. What I said is:

Quote:

---

RL-15 same components:
56.5 grs. 320 gr. Woodleigh 2380 FPS



--------------------------------------------------------------------------------



I ran this load through the software and corrected it came back within 10 fps, when the barrel length was adjusted to 26", and an adjustment was made to provided for a "hot" lot of Rel 15. However, the pressure was a tad high @ 63,792 psi

---

I guarantee you will not be able to tell 63,792 psi from 55,000 psi, THIS IS A SIMPLE FACT!!

Also, I am famaliar with the old "reloadig rule of thumb" you spoke of. It is not a good idea to use though except when scaling STARTING LOADS ! I HAVE blown primers using this "rule of thumb" before!! So it is NOT very accurate, IMHO.

Regarding modern PREMIUM strain gages and electronics. They are accurate to 5 decimal places, that is about it. The calculations I did ARE VERY ACCURATE and illustrate that even with the VERY BEST electronic data acquisition equipment, pressure reading is more of an art than a science! Unless of course SPECIALLY designed (highly weakened barrels designed to maximize strain at the strain gage) are used, but these barrels don't last long and are prone to premature catastrophic failure.

By the way, you can CALIBRATE a pressure barrel without having to use the mythical "calibration" loads, which are highly inaccurate at best!

I guess my entire point is, you should trust the pressure calculations of the software more than the pressure estimates you make based upon visbile and micrometer analysis of shot cases! The pressures calculated by my software are VERY MUCH closer to reality than your opinions of what you loads are running at! That is fact, your opinions are fiction. Sorry if the truth hurts, but it is the truth all the same.

Hey, loading to higher pressure is the reason the Ackley improved cartridges outperform the unimproved versions. You won't blow a primer till at least 70 ksi so your 9.3X62 load has some head room yet. it just violates the CIP pressure limits that is all.

ASS_CLOWN

asdf,

I suggest you learn to read. Nothing you said disagrees with me. Strain gages electronics can provide measurements to 5 decimal places, REMEMBER THEY ARE MEASURING STRAIN NOT PRESSURE!!! 1000 psi in a sporter weight barrel is 0.0000143" of strain (FIVE DECIMAL PLACES AND THEN SOME!!!) So the BEST strain gages CANNOT reliably read pressure in less than 1000 psi increments in a LIGHT WEIGHT hunting barrel. THIS IS THE REASON SO MANY RELOAD MANUALS EXCLUDE ACTUAL PRESSURE READINGS. The aftermarket systems record "peak" estimates of pressure and use filters to provide a SMOOTH curve. These aftermarket systems are good for estimating a peak pressure and post initial pressure spikes, which can be very bad! They are not overly accurate otherwise.

My statements are directed to pressure measurements of a rifle barrel! The brass deflects WITH the rifle barrel, and plastically I might add, in the "pressure ring" area for that type of measurement, therefore, you CANNOT get a good measurement as your equipment ISN'T good enough. The mechanics are: brass yields and conforms to the barrel's deflected stated during firing, unfortunately, the brass "remembers" it's non-plastically deformed condition, to a certain degree, with the result being erratic measurements of the "pressure ring". Add to this the effect of the blend radius, which is within the barrel hoop, and the nature of the erratic behaviour is increased even more. Put in the simplist terms, your gage repeatability and reproducibility SUCK!

I could care less if you wish to delude yourself with this method of "pressure estimation" it is up to you. However, if you prescribe to these delusions, please do not chastise the individuals that prescribe the reading of animal entrails for "pressure estimation". You are both of the same accuracy levels, more or less!

CASE HEADS are SOLID except for the flash hole. IF A CASE HEAD IS DEFLECTING you are BLOWING PRIMERS!

I can post pictures of sectioned cases if that will help you to understand! There is nothing too aweful technical in any of this outside the mathematics, which I do not believe we are arguing.

My entire point is a reloader should place MORE faith in a correlated simulation model, which mine is and there are others out there too, than in READING pressure by the signs!

To argue with that last statement is foolhardy, IMHO. Remember I said CORRELATED SIMULATION meaning it has been established and adjusted to match up with actual measured pressure data from a modified barrel to provide good measurement data acquisition (barrel has been significantly reduced in hoop stiffness to exaggerate hoop deflection which means the barrel is junk after 25 full SAAMI pressure loads)

ASS_CLOWN

I guess I's going to haveto agree with most of the others on this forum ASSClown, you gotta be William Tibbe or one of those clowns that screw up these forums with bullshit that you have read someplace...and you do dodge the issues when exposed...but I don't play those games so I'm out of here..You are a trol, Jeffe and 500 grs. told me so!

No Ray not Bill Tibbe, nor one of your worshippers! The FACT is you have NO CLUE to what pressure your loads operate at, YOU ONLY KNOW that they are below the plastic deformation limit of a mauser or H&H case head. That puts them squarely below 70,000 psi!



ASS_CLOWN

I asked some time back about your software to predict pressures but I guess it got lost in the heat of the argument. I picked up there is one called quickload but you also refer to yours. what are the details? Also I notice you challange the aftermarket straingage systems. Is there a better method or system available? I would have thought that given the variables and the necessary safety margin an accuracy of say +/- 5000 psi would be practical

westaussie,

The software I use is not "software" as most consider it nowadays. It is a labor intensive number cruncher. It is based upon "first law", and there are numerous steps taken to calculate several items needed to arrive at the final estimation of velocity and pressure. These steps would all be buried in a modern program, which is too bad in my opinion as it forces one to learn something about internal ballistics. It is most definitely not QuickLoad. In my application it has shown to be far more accurate than QuickLoad simulations have been.

It is more accurate with single based powders than double base, but within the realm of powders, single or double, with burn rates suitable for rifle cartridges it is very accurate. . This is doubly true when it has been correlated to measured velocity and pressure data taken from a rifle. On a side note, with most ball powders though, correlation to actual measured velocity and pressure are needed to get good simulation predictions.

Regarding strain gages. I merely wanted to point out to everyone that they have their limitations, they still are the best system we have though. In practice, strain gages cannot be relied upon to provide better than resolution than 1000 psi. Often the resolution of a strain gage system is no better than 2500 psi. Having said that, the strain gage is still FAR FAR more accurate and RESOLUTE a measurement system than is PRE, or the erroneous CHE methods. I only brought it up as I was being taken to task for provided simulation pressures to the 5 place.

I say it again, if you are YIELDING (read expanding) case heads BACK YOUR LOADS OFF 10%!!!! Of course you may not really be yielding that case head, it may just be you are confusing the micrometer for a C-clamp.

The fact still remains that the vast majority of reloaders do not have a clue to the actual pressures of their handloads. All they CAN know for certain is that their loads are below the yield strength of the case head and/or web of the cartridge they are reloading.

I can post the nominal pressures required to yield many cartridges, but I see no reason as I will only be attacked more by those that prefer to keep their heads "buried in the sand".

ASS_CLOWN

Now Clown, by "5 digits" I meant precision, not places right of the decimal. Your "0.0000143" of strain" has only 3 digits in it, of course.

Quote:

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I could care less if you wish to delude yourself

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Yes, I did misread one of your statements earlier, but you have done so here as well. I stated clearly I do not believe either CHE or PRE to be very useful, and I certainly do not use it myself.

I continue to disagree with your argument that barrel expansion causes the PRE. Your own figures list expansion on the diameter due to hoop strain to be .0008. The SAAMI specs for chambers and cartridges allow clearance from .0010 to .0050, values which are larger than barrel expansion. It was this point I was trying to make -- perhaps not clearly -- before. PRE would exist even if the barrel deflected not at all. Further, I believe PRE would increase with pressure in such a barrel as well, due to the deformation (in the flare from the sides to web) appearing further down toward the web at the higher pressure. This would cause the PRE to bulge further at higher pressures.

I agree entirely that the variable properties of brass in cartridges make PRE and CHE not worth the effort.

I found your arguement useful (even if I disagree with the conclusions). I always wondered why cases stick. Barrel relaxation onto a very badly strained case is obviously why, but the thought had not before dawned in my dim head.

Could you cite a reference for the technique you use for your hand calculations? This is not a "put up or shut up" challenge. I am genuinely interested in new approaches to internal ballistics estimations. As I said above, I am quite aware of the limitations of QuickLOAD. The program's author is not bashful about pointing out all the oversimplifications he used in its computations.

S. Faber had a more thorough program for this work, but he is no longer supporting it. He now advocates strain gauges instead. I do, though, find programs such as QuickLOAD useful in demonstrating trends. I'm always willing to learn more.

Finally, I do agree the strain gauge is the best approach out there. Combined with a chronograph, it should provide a clear view as to which powder is developing the desired fps with the lowest peak pressure and pressure rise.

Karl

asdf,

Obviously the chamber is larger in size than the cartridge, otherwise said cartridge would not fit into said chamber. The vast majority of the PRE you measure is due to the plastic deformation of the brass case deflecting to the contour of the chamber. There is a small, relatively speaking, additional amount of brass deformation possible due to barrel radial and longitudinal deflections. The barrel supports the brass otherwise the brass case would literally explode, at least in all modern high intensity (read greater than 45000 psi) loads.

I am glad to see that you grasped the concept of the deformed brass gripping the walls of the relaxed chamber! Brilliant, absolutely brilliant, I am proud of you (and I mean that very seriously). This is the reason that extraction cams exist, it amazes me how many people argue that one!

Regarding the hand calculation, I assume you are referring to the hoop strain? Practically any Strength of materials or machine design book should provide you with all the necessary building blocks to begin, and ultimately finish the derivation.

It begins like this, with the fundamental definition of Young's Modulus (now called the Modulus of Elasticity "E").

E = principal stress / principal strain

principal stress is also called unit stress (at least when I was in school)

principal strain is also called unit strain (at least when I was in school)

I do pick up new vocabulary from the younger guys. Usually when they are trying to show the old man how it is done, once in awhile they are even right!

Since we live in a three dimensional world, you will need to solve for the triaxial stresses as they interact with the principal strain of interest, in this case that is the Hoop strain.

If you are referring to the internal ballistics program, I would direct you to a thermodynamics textbook. Just let you mind run free with the first law of thermodynamics. Internal ballistics is a thermodynamic expansion. The problem with most textbooks is at they deal with a steam (pressurized water vapor) expansion instead of a combustion process. So after you have familiarized yourself with the first law of thermodynamics, I strongly recommend that you study up on the combustion dynamics of internal combustion engines. Study both the Diesel and Otto thermodynamics cycles. Finally, there is a considerable degree of analytical work, as well as, experimentation needed to get it mostly right, but that is where the fun is.

I do not believe you will benefit from me spending a hour or two here typing in equations and technical clarification statement to support derivation develop as you may or may not have a clue as to what I am typing about. So I stongly recommend you get the resource material I spoke of and teach it to yourself. I learn best this way, and I have found most others do as well. Believe me, if you study this to the point you can perform the derivations and generate the necessary equations, correlate them to real experimentally gathered data, you will have a very good understanding of internal ballistics, among other things. Learning is one of the greatest passions one can experience in life, at least IMHO.

ASS_CLOWN