44WCF and Reloader 7.

[BobInAus]

Hey guys, back in 2018 I had a bit of discussion with Savvy Jack and Outpost75 regarding a load with Accurate 43-245gr mold (249gr of 50:1 lead /tin) and Reloader 7 for my 44WCF in a 1873 Winchester (circa 1892). Well it became a little convoluted with my misunderstanding the term ‘Capacity load’ of RL 7.

Well since that time I have been playing with my Winchester 200grn antique mold and an ideal mold of 215gr.

So I thought I would try and get it all sorted out – I did some math’s with a 44WCF case. I established that the .249” bullet measured .416” from base to the crimp groove, then 1.138” from shell top to the inside bottom of the shell and then .722” from inside bottom of the case to a position inside the case that corresponded with the bottom of the 245 bullet. I then dropped an amount of Rl 7 that filled the case to the position that would be occupied by the bottom of the 245gr bullet. I then weighed the amount of powder which turned out to be a neat 24 grains.

Now the big question, is that 24 grains a ‘capacity load’ because it fills the case to the bottom of the bullet.

How does that 24gr load stand against the 249gr bullet when compared to
Alliant’s load of 23.5grs behind the 240gr bullet - Pressure etc.

I would appreciate any information regarding this matter.
Bob

[Outpost75]

BobInAus

Great question. In your original 1873 I would consider your 24 grain charge of RL7 quite safe with a 249-grain bullet, because when a longer, heavier bullet is seated to an overall cartridge length which feeds reliably in the rifle, deeper seating of the bullet also reduces powder capacity. In loading RL7 I would consider a "full case capacity" load as one which provides base support for the bullet in the same manner in which black powder does, such that a traditionally-designed bullet does not require a crimp groove to prevent its being "telescoped" back farther into the case under compression of the magazine spring. This is achieved by bulk loading the powder without the use of a long drop tube or compression die, but the bullet base may provide "slight" compression of 2-3mm as the bullet is seated.

[ndnchf]

I can't really help with your question. But I'll say that I really like RL7 in the .44WCF. My go-to load is 25.0gr under a 30-1 Ideal 427098 bullet with CCI LP primers. Its good for 1300fps from my 24" barreled M1892. Its great in my M1873 carbine too.

[veeman]

would these loads be considered too hot for the modern colt saa?

[ndnchf]

would these loads be considered too hot for the modern colt saa?

25gr of RL7 and the 427098 bullet is about equal to the original black powder load for both velocity and pressure. Read about the late John Kort's testing and a whole lot more here: https://sites.google.com/view/44winchester/44-40-Winchester

[Outpost75]

would these loads be considered too hot for the modern colt saa?


Not too hot, but RL7 doesn't burn well in revolvers.

269002

[BobInAus]

That is really good info. Thanks a lot blokes, it is really appreciated. Outpost75, I'll get on that load today. I have a good feeling it is going to be a killer load.
Bob.

[Outpost75]

That is really good info. Thanks a lot blokes, it is really appreciated. Outpost75, I'll get on that load today. I have a good feeling it is going to be a killer load.
Bob.

Please let us know how it works for you and post targets or field reports of game shot.

Getting confirmation from firings in original rifles is always beneficial.

[Kosh75287]

Not too hot, but RL7 doesn't burn well in revolvers. That's a valid point, but I wonder if it might burn okay (or at least better) in a 7 & 1/2" barreled Peacemaker. Just thinking out loud.

[Savvy Jack]

That's a valid point, but I wonder if it might burn okay (or at least better) in a 7 & 1/2" barreled Peacemaker. Just thinking out loud.

Reloder 7 burns too slow for revolvers if you are looking for velocities. I use it BUT velocities can be 200fps slower than using other powders.

I used 24gr of Reloder 7 with a Hornady 240gr SWC HP for hunting. Harvested a deer in SC at 65 yards. Hit shoulder broadside, turned 90 degrees and traveled down the spinal cord. It lodged in the hind quarter. A bit overkill ;-)

I think the 250gr would be fine.

[BobInAus]

Will do Outpost75. Whilst I'm "keen as" I won't be able to get out for a while. I suffered a detached righthand retina and no driving for 6 - 8 weeks. A real pain in the proverbial being right handed. Any way I'll get somethin up when I get out.

Bob

[Larry Gibson]

In a recent testing (Vicarious 44-40 Pressure Testing) I pressure tested 25 gr RL 7 under the Lee TL429-240-SWC in the 44 Magnum.

http://castboolits.gunloads.com/showthread.php?406689-Vicarious-44-40-Pressure-Testing

It was found, by vicarious comparison the 44-40 with the same load would give 94 - 95% the same psi. That load generates about 23,000 psi in a 44-40. I also chronographed that load in W-W 44-40 cases in a Ruger OM Vaquero with 7 1/2" barrel and a M92 Cimarron Chiappa with a 20" barrel. The velocity ran 1157 fps out of the Vaquero and 1488 fps out of the M92. The RL 7 load with the 240 gr bullet did well in the revolver with an SD of 18 fps and an ES of 62 fps for the 10 shot test. That is pretty good for a revolver. However, as Outpost75 mentions, with the 200 - 210 gr bullet it does not burn all that efficiently in the revolver leaving unburned powder.

[Savvy Jack]

In a recent testing (Vicarious 44-40 Pressure Testing) I pressure tested 25 gr RL 7 under the Lee TL429-240-SWC in the 44 Magnum. It was found, by vicarious comparison the 44-40 with the same load would give 94 - 95% the same psi. That load generates about 23,000 psi in a 44-40. I also chronographed that load in W-W 44-40 cases in a Ruger OM Vaquero with 7 1/2" barrel and a M92 Cimarron Chiappa with a 20" barrel. The velocity ran 1157 fps out of the Vaquero and 1488 fps out of the M92. The RL 7 load with the 240 gr bullet did well in the revolver with an SD of 18 fps and an ES of 62 fps for the 10 shot test. That is pretty good for a revolver. However, as Outpost75 mentions, with the 200 - 210 gr bullet it does not burn all that efficiently in the revolver leaving unburned powder.

Very interesting information Larry.

I have been wanting to post the following on Cast Bullets Association forum but never got around to it.

I found that different design 240gr bullets varied a lot in pressures when using Reloader 7 with the strain gauge.

All 240gr Bullets. I don't have the diameters handy but typically .429/.430
All loads Reloder 7

25gr/3D LRNFP/1,300fps/9,613 psi
23.5gr/ACME Hi-Tek SWC/1,284 fps/9,761 psi
26gr/Georgia Arms L44A SWC/1,441 fps/14,247 psi
25gr/ACME Hi-Tek SWC/1,420 fps/14,542 psi
26.5gr/43-230G(240gr)/1,506 fps/14,737 psi
25gr/SDCHP/1,350 fps/15,248 psi
25.3gr/Lee 3Crimp(forget name)/1,446 fps/15,279 psi
27.5gr/GA L44A/1,541 fps/16,743 psi

I hope you can get a 44-40 barrel for the Contender and check those loads against mine with the PTII!!! You will also have to get some Buffalo Bore loads and set the PTII for those loads to 11,300psi THAT is the only catch-all to this whole thing on my end.

[indian joe]

How come you blokes (Larry and Bryan) are 8000psi apart with your pressure readings. ?
I have been following this subject with interest (and a bit of scepticism at the low numbers ) from a ways back . Used RE7 years ago to get the best velocity (according to Hornady manual) from a 375 Big Bore Winchester - cant remember the load - 38 grains maybe? - didnt have a chrono then but it did the business - that rifle bit at both ends - so reading about full case loads and equivalent to blackpowder pressure/velocities in the 44/40 has took a bit of digesting - I cant test pressure and my blackpowder comes free (almost) so have just sat and watched and wondered......... have to say at this point Larry's numbers are easier for me to digest. 15k vs 23k is a large spread???? is this about calibration of equipment .....................
could easy be that I under estimate the pressure from a decent blackpowder load too.............

[Savvy Jack]

How come you blokes (Larry and Bryan) are 8000psi apart with your pressure readings. ?


Larry is working on hearsay from years ago trying to confirm or bust. So far he is testing the 44 Magnums but using a formula, to include velocity to come up with a pressure for the 44-40. It is really guess work. I sent Larry my Pressuretrace system but he needs to get a barrel for testing. Larry's theory is here: https://sites.google.com/view/44winchester/contributors/larry-gibson


My tests are actual pressure tests BUT I had to use Buffalo Bore's" factory loads as a "control". All of my tests (83 = 830 shots) parallel published load data. If Buffalo Bore is correct at being right at max SAAMI loads, then the majority of my replicated Lyman 49th loads are just under published pressures...as expected. They will not published exact max loads and will use a "buffer" that is just under max loads. I discovered that Winchester Super-X hunting loads are 3,000 psi under MAX which is a typical pattern I find even with published load data. What really satisfied me is when I tested black powder loads in original cases and came up with parallel results with loads over the years. 14,000 psi, then down to 12,000 psi, then 10,000 psi then 9,000 psi with modern components. If I am incorrect, then this forces those BP results to be higher than recorded. Can you imagine 44-40 black powder cartridges to produce higher than 14,000 psi? Me either!! This also means that if Buffalo Bore is not 11,300 PSI, then they are loaded hotter than SAAMI max and they claim they are safe for revolvers....I think not, they must be loaded to SAAMI max!! https://www.buffalobore.com/index.php?l=product_detail&p=513


Original 200gr. lead (not hard cast, but lead) bullets achieved around 1,000 fps from 7.5-inch barreled revolvers of the day and 1,300+ fps from rifles. Our new loads do that and a bit more with smokeless powders while staying within the black powder pressures of 13,000 CUP as a maximum average pressure.

If BB is using cup and not psi, either way 13,000 cup is equal to 11,000 psi SAAMI MAP pressures. 11,300 is Max Lean.
https://saami.org/wp-content/uploads/2019/02/ANSI-SAAMI-Z299.4-CFR-Approved-2015-12-14-Posting-Copy.pdf CUP page 21, PSI page 33

Lastly, there were published loads for the 240gr bullets and Reloder 7, 23.4gr, 1,200 pfs @ 11,000 psi....my results were 23.5gr/ACME Hi-Tek SWC/1,284 fps/9,761 psi, much closer than an 8,000 psi difference. Because of the different results with different design 240gr bullets could be why the data was no longer published. Also, bullets with different lead content, soft vs hard, along with large diameter vs smaller diameter also affect pressures.....especially when trying to cram a hard cast .430 bullet down an older .424 bore!!!!

This does not mean I am correct by any means, it just means I have an exhaustive data collection from actual physical test, rather than just "formulas and theories", that parallels published data that is consistent.

We need more folks out there to "fill-in" these gaps. Larry's tests are important for comparisons.

I have also published all of my findings for the public to give feedback.

https://drive.google.com/file/d/1L4CrfgL59_4nBSq-FzUgyMuCc_oylycZ/view?ths=true
https://drive.google.com/file/d/1CaznOM73RP8KcV7kdEQ05c75nlumGNZw/view
https://docs.google.com/spreadsheets/d/1cZyKKXVyHq9as9uFJiko5yReJ9a-ER32YsENTgJGJs4/edit (click the powder tabs at the bottom of the screen)

It is not perfect by any means and all my guns with hundreds and hundreds, if not thousands, of rounds through them....non blown up, stretched, nor worn out yet.

In this current test that I just made regarding bolt thrust pressure, I found that at about 7,000 psi, the 44-40 case will thrust into the bolt. This psi is based on my pressure test results.
https://sites.google.com/view/44winchester/handloading/bolt-thrust-pressure

[indian joe]

Larry is working on hearsay from years ago trying to confirm or bust. So far he is testing the 44 Magnums but using a formula, to include velocity to come up with a pressure for the 44-40. It is really guess work. I sent Larry my Pressuretrace system but he needs to get a barrel for testing. Larry's theory is here: https://sites.google.com/view/44winchester/contributors/larry-gibson

I disagree with Larrys stated/assumption that 44 mag and 44/40 cases are, for practical purposes same capacity -- 44/40 is bigger by two or three grains of black at least and that shows in the 93% pressure reading he quotes - not a lot of difference but some

I focussed on his "25 gr RE7 = about 23000psi for the comparison I made" - yeah cherrypicked that a bit !

With 40 grains FFFg under a RCBS 205 grain I had 1355fps - 39 grains got 1339fps (24inch rifle barrel) --
I would be really interested in a pressure read for a load using 3 grains 4227 under 36 grains of FFFg blackpowder and the 200grain/205grain boolit . I believe that would get velocity over 1400fps - at what cost in pressure?



My tests are actual pressure tests BUT I had to use Buffalo Bore's" factory loads as a "control". so thats your calibration?

All of my tests (83 = 830 shots) parallel published load data. If Buffalo Bore is correct at being right at max SAAMI loads, then the majority of my replicated Lyman 49th loads are just under published pressures...as expected. They will not published exact max loads and will use a "buffer" that is just under max loads. I discovered that Winchester Super-X hunting loads are 3,000 psi under MAX which is a typical pattern I find even with published load data. What really satisfied me is when I tested black powder loads in original cases and came up with parallel results with loads over the years. 14,000 psi, then down to 12,000 psi, then 10,000 psi then 9,000 psi with modern components. If I am incorrect, then this forces those BP results to be higher than recorded. Can you imagine 44-40 black powder cartridges to produce higher than 14,000 psi? Me either!! This also means that if Buffalo Bore is not 11,300 PSI, then they are loaded hotter than SAAMI max and they claim they are safe for revolvers....I think not, they must be loaded to SAAMI max!! https://www.buffalobore.com/index.php?l=product_detail&p=513



If BB is using cup and not psi, either way 13,000 cup is equal to 11,000 psi SAAMI MAP pressures. 11,300 is Max Lean.
https://saami.org/wp-content/uploads/2019/02/ANSI-SAAMI-Z299.4-CFR-Approved-2015-12-14-Posting-Copy.pdf CUP page 21, PSI page 33

Lastly, there were published loads for the 240gr bullets and Reloder 7, 23.4gr, 1,200 pfs @ 11,000 psi....my results were 23.5gr/ACME Hi-Tek SWC/1,284 fps/9,761 psi, much closer than an 8,000 psi difference. Because of the different results with different design 240gr bullets could be why the data was no longer published. Also, bullets with different lead content, soft vs hard, along with large diameter vs smaller diameter also affect pressures.....especially when trying to cram a hard cast .430 bullet down an older .424 bore!!!!

This does not mean I am correct by any means, it just means I have an exhaustive data collection from actual physical test, rather than just "formulas and theories", that parallels published data that is consistent.

We need more folks out there to "fill-in" these gaps. Larry's tests are important for comparisons.

I have also published all of my findings for the public to give feedback.

https://drive.google.com/file/d/1L4CrfgL59_4nBSq-FzUgyMuCc_oylycZ/view?ths=true
https://drive.google.com/file/d/1CaznOM73RP8KcV7kdEQ05c75nlumGNZw/view
https://docs.google.com/spreadsheets/d/1cZyKKXVyHq9as9uFJiko5yReJ9a-ER32YsENTgJGJs4/edit (click the powder tabs at the bottom of the screen)

It is not perfect by any means and all my guns with hundreds and hundreds, if not thousands, of rounds through them....non blown up, stretched, nor worn out yet.

In this current test that I just made regarding bolt thrust pressure, I found that at about 7,000 psi, the 44-40 case will thrust into the bolt. This psi is based on my pressure test results.
the bolt thrust stuff is really interesting .. I cant play any videos at this point graphics card in my puter is karked it
https://sites.google.com/view/44winchester/handloading/bolt-thrust-pressure
......

[Larry Gibson]

"How come you blokes (Larry and Bryan) are 8000psi apart with your pressure readings. ?"

indian joe asks a very good question.

If one reads my post/thread on "Vicarious 44-40 Pressure Test" you'll see my pressure estimate is an "educated" assumption based on pressure testing the load in a 44 Magnum along with comparing the velocity results of that load in both the 44-40 and 44 Magnum cartridges in the same revolver. The Contender test barrel (44 magnum) was tested with Hornady 240 gr XTP ammunition as "reference ammunition" of which I had the factory tested psi of that lot of ammunition. The Contender test barrel with the M43 PBL measured the psi of the Hornady factory ammunition to within 300 psi of the factory measurement.....well within test to test variation.

After several different discussions with Dr. Oehler and several attempts at finding any correlation between CUP and psi measurements I found that endeavor futile, as Dr. Oehler said it would be. Recently SAAMI has updated there specifications with more complete specifications. One of the cartridges updated is the 44-40. Past factory loadings of 44-40 ammunition have given us 2 and possibly 3 different levels (velocity and pressure) ammunition. We even find 3 different levels for various strengths of actions, 2 such levels in Lyman's manuals which exceed the new SAAMi . We must also consider and understand how SAAMI arrives at the MAPs listed. SAAMI does not develop loads. SAAMI tests factory loads. SAAMI also will list some +P specification for those +P cartridges that are factory loaded. SAAMI does not list different levels of loads as are commonly loaded in several cartridges such as the 45 Colt and the 45-70. To establish the MAP/MPLM/MPSM for a cartridge SAAMI's procedure calls for the pressure testing of factory ammunition. Todays 44-40 ammunition is all basically "cowboy action" loads. Thus is, I surmise, the reason for the very low MAP of 11,000 psi for the 44-40 cartridge. only current factory ammunition was tested. As to the Oehler M43 PBL difference of psi with other sources I can say this; I test the pressures in numerous test firearms for 37 different cartridges. I have conducted thousands of pressure tests over the last 14 years. Each test barrel has been "calibrated" with "reference ammunition" of known psi. The psi measurements taken with the Oehler have been consistent with other actual test psi measurements.

I also have learned to not give too much credence to reported pressures unless the method of measurement is specified along with the test parameters. Is a previously published "240gr bullets and Reloder 7, 23.4gr, 1,200 pfs @ 11,000 psi" correct? Given there is only 5% difference in case capacity between the 44 Magnum and the 44-40 are we to really believe it requires 35 to 39,000 CUP in the 44 Magnum to get 1200 fps with a 240 gr bullet (Lyman #4 CBH) but the same velocity is attainable in the 44-40 with only 13,000 CUP? I don't think so but we shall see.

So why is there 8,000 to 12,000 psi difference between what I estimated and what Savvy Jack found.....that is a good question. On Monday or Tuesday (hopefully) I shall attempt to make direct comparison between the measurement the Pressure Trace II System [PT II] takes as compared to the measurement the Oehler M43 PBL takes. Savvy Jack sent me his Pressure Trace II system. I've had it checked out by the manufacturer and have it functioning with another laptop. I am confident it is a good system. To make a direct comparison of pressure measurements I will use my 308W test rifle and have added another strain gauge on the opposite side of the barrel. Thus, I should be able to measure the pressure of each cartridge fired with both systems simultaneously. That will give a direct comparison and should provide an answer. This will take a bit of set up time at the range with both systems and two laptops. It also means I'll have to leave the shooting bench between shots to verify the measurement was taken and add data into the PT II. I have been practicing using the PT II program so I am comfortable with it now. The results should prove interesting.

[Larry Gibson]

indian joe

"I disagree with Larrys stated/assumption that 44 mag and 44/40 cases are, for practical purposes same capacity -- 44/40 is bigger by two or three grains of black at least and that shows in the 93% pressure reading he quotes - not a lot of difference but some"

Obviously you have not read "Vicarious 44-40 Pressure Test". Had you read that you would have found what i said right up front was;

"Based on Savvy Jack and Outpost75s exchange I wondered if there was a way to correlate pressures obtained in the 44 magnum cartridges to the 44-40 cartridge(?). I had measured the case capacity of both cartridges using RL7 powder and found the case capacity of the cartridges (both were W-W cases) was very close.

I had read in the past that given equal loads the pressures in the 44-40 would be about 95% of those in the 44 Magnum."

Had you read the conclusion after the test was completed you would have read;

"All loads in 44-40 cases gave less fps than the same load in 44 magnum cases in the same revolver. The average difference is the 44-40 produced, on average, 93.4% as much velocity in the 44-40 cases as the same load did in the 44 Magnum cases. That does seem to suggest that what I had read years back about the 44-40 producing 95% +/- as much psi as with the same load in a 44 Magnum case is correct. So, is there a correlation we can use to determine safe pressure 44-40 loads with pressure testing being done in the 44 Magnum pressure test barrel? It appears so. Since all was equal in the revolver except the chambering and since velocity is directly related to pressure [all other equal as was in this test] I think we can safely conclude a load that produces so much pressure in the 44 Magnum will only produce 93 – 95% of that pressure in the 44-40 cartridge."

The results of my testing demonstrate just about the same difference in capacity [exception being I used cases of the same make for both cartridge for the comparison] as you've come up with.

Little to no "disagreement" that I can see?

Also, your assumption of "I focussed on his "25 gr RE7 = about 23000psi for the comparison I made" - yeah cherrypicked that a bit !" is completely incorrect. That was the load of RL 7 tested which was in answer to the OPs question with the psi reduced by the amount based on the test results. That load of RL 7 under the 240 gr bullet produced 24,400 psi in the 44 magnum as tested. It should, therefore, produce 23,000 psi in the 44-40 as stated. No "cherry picking" involved at all.

[Savvy Jack]

"How come you blokes (Larry and Bryan) are 8000psi apart with your pressure readings. ?"

Is a previously published "240gr bullets and Reloder 7, 23.4gr, 1,200 pfs @ 11,000 psi" correct?

So why is there 8,000 to 12,000 psi difference between what I estimated and what Savvy Jack found.....that is a good question. On Monday or Tuesday (hopefully) I shall attempt to make direct comparison between the measurement the Pressure Trace II System [PT II] takes as compared to the measurement the Oehler M43 PBL takes. Savvy Jack sent me his Pressure Trace II system. I've had it checked out by the manufacturer and have it functioning with another laptop. I am confident it is a good system. To make a direct comparison of pressure measurements I will use my 308W test rifle and have added another strain gauge on the opposite side of the barrel. Thus, I should be able to measure the pressure of each cartridge fired with both systems simultaneously. That will give a direct comparison and should provide an answer. This will take a bit of set up time at the range with both systems and two laptops. It also means I'll have to leave the shooting bench between shots to verify the measurement was taken and add data into the PT II. I have been practicing using the PT II program so I am comfortable with it now. The results should prove interesting.


I just can't tell you how much I have my fingers crossed!!! If the Oehler and the Pressuretrace results are close with Larry's 44 Magnum loads, then it proves my consistency is consistent, but would not confirm my "control" load's results which is Buffalo Bore's factory loads. What we don't know is if BB actually got some pressure testing cartridges from SAAMI or just tested their own.

The 240gr RL loads was published by Lee Precision, but I have no idea if it was their load or a"parrott" load. That load was also published by Alliant and Hercules. I would certainly trust Hercules, more than likely Alliant as well but I fell Lee is just duplicating both Hercules and Alliant's 2005 data. Although they specify 240gr, they do not specify what particular bullet which can be crucial.

Here is a bit of what it takes to test the 44-40.

https://sites.google.com/view/44winchester/handloading/pressure-testing


"44-40 pressures,

SAAMI barrels have minimum chambers and nominal bore dimensions. To mimic one, you have to get a barrel blank made to their bore cross-sectional area dimensions and then chamber it with a special reamer ground to produce the SAAMI minimum chamber diameters and not run it in past half a thousandth beyond what produces SAAMI minimum headspace. That's ±¼ of a thousandth, which can take some skill to do. Standard reamers are commonly made a little wider so they can be resharpened without losing dimensional precision. Denton Bramwell points out in the article [Link] most chambers made with standard reamers can expect to produce lower numbers.

SAAMI test barrels are fired with the cartridge manipulated to ensure the powder has fallen back over the flash hole. They are not tapped against anything to do this, as that packs the powder which can lower its burn rate a little. They want worst case highest pressure, so they just turn the case around to let the powder fall back to the rear, then load it carefully so as to avoid shifting the powder position. If you don't do that, you will get lower numbers than they do.

For rifle cartridges, SAAMI expects no more than 4% standard deviation in pressure. If your readings produce a higher SD than that, you are probably using a sample too small to be relied on to produce a good SD number. SAAMI uses ten rounds. Our own board member, Statshooter, who is a professor of statistics, says 30 rounds are needed. Denton Bramwell feels 15 rounds give him what he needs to know. So, why does SAAMI just use 10? They accept the SD results produced by 10 can be off on the high side by two standard errors (about another 2.5%), so they have a second number in addition to the MAP called the Maximum Probable Lot Mean, or MPLM, that allows the next sample of 10 from the same lot could produce a standard deviation that was different by that much. So, while the MAP is 11,000 psi, they allow they might get an average as high as 11,300 psi from another random sample of 10 from the same lot, and that is acceptable. They have a still higher number, called the Maximum Probable Sample Mean (MPSM) that allows that bullet bonding with the case and other factors can produce an increase in pressure as a lot of ammunition ages, and for the 44-40 that number is 11,700 psi. So, in effect, they are saying 11,700 psi is the safe limit, but, wait, there's more: All those numbers, the MAP, the MPLM, and the MPSM are averages produced by 10 round samples. The individual rounds making up that average will go above and below that average. SAAMI controls that by allowing what they call the Maximum Extreme Variation (MEV) which is the maximum spread between pressure readings for any of the 10 rounds in any sample taken at any time in the life of the lot. For the 44-40, the MEV is 2300 psi (this has to be calculated per the standard's instructions; it is not in a table). Theoretically, you could have aged loads centered on 11,700 psi whose 10 shots had one round as high as 13770 psi that would still be acceptable to SAAMI (though it is extremely improbable as it requires all 9 other shots to be exactly 11,470 psi). Mostly, though, you don't see individual rounds more than about ten percent above the MAP.

Even with all of that care, the fact is the absolute pressures are not exactly knowable. SAAMI reference cartridges are made in lots that are sent around to member's test facilities every two years to watch for reading changes. The members use SAAMI standard calibration methods (see the SAAMI standard) and report their results for both pressure and velocity from SAAMI standard test barrels. Interestingly, these vary more than the SAAMI standard deviation limit. The old 1992 standard gave an example for each method firing the same lots of reference loads, and the copper crushers, using targe tables for calibration, produced over 23% difference in average pressure for 10 shots among 9 labs. The transducers, using hydraulic pressure for calibration, produced over 11% difference in 10-shot averages among 7 labs. The reported results for each set of tests from each lab were, in turn, averaged and the final average was declared to be the pressure value that reference lot produced. This way, in effect, the reference lot pressure in the example was evaluated by looking at 90 and 70 total sample shots for the crusher and transducer, respectively. It compensates for average measurement calibration and operation errors, combined, to give a practical expected correct reading.

That approach may seem a bit tenuous, but understand the objective is to get everyone producing ammunition to the same standard, even if its absolute accuracy is not perfect. When a manufacturer wants to load a million rounds in a particular chambering, he buys a sample of a current lot of reference ammunition for that chambering and fires it in his own test equipment and compares his results to its agreed-upon rated pressure. This gives him a calibration factor for correcting his equipment's output to match the average output produced by the rest of the test labs that measured the lot. In the end, he doesn't load to the raw pressure readings his equipment provides, but to pressure readings corrected by what the reference load told him was his equipment's error factor.

So, if you wanted to compare strain gauge results to commercial equipment, one would ideally get some SAAMI reference ammunition to calibrate to. Unfortunately, reference ammunition is only sold to ammunition makers or others who can show a real need to have it. Otherwise, I think, they fear a run on it would occur that could interfere with the industry.

I notice all Hodgdon's psi-rated loads for the 44-40 exceed the SAAMI MAP, while their CUP-rated loads (in their pistol section) do not. Makes me wonder if someone confused the digits? It's still below the CIP's pressures, but those are measured on a different style of transducer (a channel transducer).

Regarding CUP ratings in manuals, while the correlation between CUP and psi is too poor for reliably converting one unit to the other over a range of chamberings, within a single chambering the conversion by the ratio of the CUP and psi maps within the SAAMI system is going to be close enough for practical work. That is, 11000 psi divided by 13000 CUP is 0.846 psi/CUP for the 44-40, so you can take the CUP numbers in the Lyman Manual and multiply them by 0.846 to get a reasonable expectation of psi. Conversely, dividing psi by that same number will come close to CUP." ~Uncklenick

This is part of how I conclude a relation between psi and cup for the 44-40 ONLY. SAAMI performed two separate tests using the 44-40 test sample cartridges. One tests was using the copper crusher method and the other in the piezo strain gauge. The copper crusher method resulted in 13,000 cup and the Piezoelectric method results were 11,000 psi. Two separate tests method but using approved sample ammunition from the same "batch".

That is pretty much all the definite numbers we have. Next is the High Velocity loads by Winchester. Early loads were labeled as "Low Pressure" but we have no idea what that was. Later one when the powder was switched, loads were recorded to a max of 22,000 cup. So how do I relate my HV load pressures? I have to use Lyman's HV loads for Group II rifles. Since there seems to be a certain percentage of a safety margin, I concluded that 18,500 psi 44-40 loads are close to 22,000 cup. I typically use 18,000 psi when referring to HV max psi loads.

If folks will look at my data, they can see the resemblance and consistency, along with "Unclenicks" 0.846 conversion formula for such low pressures. I am using references from several different sources and combining them into a relation to see if there is any consistency.This is where Velocity come into play. It is last on the list and velocities are consistent with historical documented velocities.

It is paramount that if folks want to understand why I came to my conclusions that they read all of my data. The following is the absolute most simplest I could make it.

https://drive.google.com/file/d/1L4CrfgL59_4nBSq-FzUgyMuCc_oylycZ/view?ths=true

[Larry Gibson]

"Regarding CUP ratings in manuals, while the correlation between CUP and psi is too poor for reliably converting one unit to the other over a range of chamberings, within a single chambering the conversion by the ratio of the CUP and psi maps within the SAAMI system is going to be close enough for practical work. That is, 11000 psi divided by 13000 CUP is 0.846 psi/CUP for the 44-40, so you can take the CUP numbers in the Lyman Manual and multiply them by 0.846 to get a reasonable expectation of psi. Conversely, dividing psi by that same number will come close to CUP."

That's the theory and what we would think. However, as i was told by Dr. Oehler that such conversions work sometimes but most often not. The reason being that smokeless powder many times, if not most often behave differently as the pressure increases. The conversion factors assume the pressure increase/decrease is always linear in proportion. It's not always so which i also found out. That is why ballisticians will tell you "there is no direct correlation between CUP and psi measurements". The only direct correlation, if any at all, will be only comparing the identical load tested in each method to each other. What happens in between is almost always a different story.

[Savvy Jack]

"Regarding CUP ratings in manuals, while the correlation between CUP and psi is too poor for reliably converting one unit to the other over a range of chamberings, within a single chambering the conversion by the ratio of the CUP and psi maps within the SAAMI system is going to be close enough for practical work. That is, 11000 psi divided by 13000 CUP is 0.846 psi/CUP for the 44-40, so you can take the CUP numbers in the Lyman Manual and multiply them by 0.846 to get a reasonable expectation of psi. Conversely, dividing psi by that same number will come close to CUP."

That's the theory and what we would think. However, as i was told by Dr. Oehler that such conversions work sometimes but most often not. The reason being that smokeless powder many times, if not most often behave differently as the pressure increases. The conversion factors assume the pressure increase/decrease is always linear in proportion. It's not always so which i also found out. That is why ballisticians will tell you "there is no direct correlation between CUP and psi measurements". The only direct correlation will be with the identical load tested in each method. What happens in between is almost always a different story.

Absolutely, I agree 100%

I would only advise the use of it for already published loads, for min published loads, in between and for max published loads. Check for consistency, I found consistency in my use for ONLY the 44-40 and with ONLY certain bullets.....and in conjunction with the strain gauge results. Notwithstanding Larry's tests with 44 Magnum and 44-40...Do not, I repeat...DO NOT base your typical loads on 44-40 (1,325fps) velocities and think you can stay under 11,000 psi.

I had to take data from several sources and combine them. If they were consistent, I published them. Oh and for those using Quickload for the 44-40, dump it QUICK!

Mush of my data depended on several combined resources...

1. SAAMI 11,000 psi/13,000 cup
2. Lyman's 49th data for Group I and Group II rifles. I could not have "confirmed" my data if it had not been for Lyman's high pressure load data.
3. Hercules/Alliant's Reloder 7, 240gr load data
4. Historical information on original powders used for the 44-40 rifle vs revolvers
5. Historical Factory Loads and Sharp's Handloading Data from the 1930's
6. Combination of all of my data being consistent. Wrong maybe, but consistent ;-)
7. Winchester's 44-40 gradual decline in performance
8. SAAMI's History timeline and how that affected the performance of the old black powder cartridge firearms.

[Hootmix]

Dang !! ,Bryan you and Larry need to post more on this subject,, I'm down to "1 un read post !!!" (lol-lol-lol-)
Love it !!

coffee's ready ,, Hootmix.

[Savvy Jack]

Dang !! ,Bryan you and Larry need to post more on this subject,, I'm down to "1 un read post !!!" (lol-lol-lol-)
Love it !!

coffee's ready ,, Hootmix.

I am not ready, just call me Grasshopper, and I have yet to grab the pebble from my master's hand!!!!

BobInAus, sorry for the hijack, I forgot where I was replying too!!!

[indian joe]

I just can't tell you how much I have my fingers crossed!!! If the Oehler and the Pressuretrace results are close with Larry's 44 Magnum loads, then it proves my consistency is consistent, but would not confirm my "control" load's results which is Buffalo Bore's factory loads. What we don't know is if BB actually got some pressure testing cartridges from SAAMI or just tested their own.

The 240gr RL loads was published by Lee Precision, but I have no idea if it was their load or a"parrott" load. That load was also published by Alliant and Hercules. I would certainly trust Hercules, more than likely Alliant as well but I fell Lee is just duplicating both Hercules and Alliant's 2005 data. Although they specify 240gr, they do not specify what particular bullet which can be crucial.

Here is a bit of what it takes to test the 44-40.

https://sites.google.com/view/44winchester/handloading/pressure-testing



This is part of how I conclude a relation between psi and cup for the 44-40 ONLY. SAAMI performed two separate tests using the 44-40 test sample cartridges. One tests was using the copper crusher method and the other in the piezo strain gauge. The copper crusher method resulted in 13,000 cup and the Piezoelectric method results were 11,000 psi. Two separate tests method but using approved sample ammunition from the same "batch".

That is pretty much all the definite numbers we have. Next is the High Velocity loads by Winchester. Early loads were labeled as "Low Pressure" but we have no idea what that was. Later one when the powder was switched, loads were recorded to a max of 22,000 cup. So how do I relate my HV load pressures? I have to use Lyman's HV loads for Group II rifles. Since there seems to be a certain percentage of a safety margin, I concluded that 18,500 psi 44-40 loads are close to 22,000 cup. I typically use 18,000 psi when referring to HV max psi loads.

If folks will look at my data, they can see the resemblance and consistency, along with "Unclenicks" 0.846 conversion formula for such low pressures. I am using references from several different sources and combining them into a relation to see if there is any consistency.This is where Velocity come into play. It is last on the list and velocities are consistent with historical documented velocities.

It is paramount that if folks want to understand why I came to my conclusions that they read all of my data. The following is the absolute most simplest I could make it.

https://drive.google.com/file/d/1L4CrfgL59_4nBSq-FzUgyMuCc_oylycZ/view?ths=true

There was a concerted effort during the 1960's -70's to push velocities for the 44/40 to what I think were irresponsible levels, 2000 FPS loads showed in several loading manuals of that time - so do we maybe take the pressure figures from that era with a grain of salt ? or conclude they were crazy and figured things out after they blew a few guns up?

from the Aussie "Reloading Simplified 1973" (in the rifle section NOT pistols) - 200 grain jacketed SP
Dupont 4227 - 29 grains = 2000FPS
ICI 2202 - 29 grains = 1995FPS
Nobels Revolver No1 27 grains = 2000FPS

in the suggested load column they drop two grains for 1850FPS

at the bottom blackpowder 33 grains is guessed at 1300FPS
(33gains of black more likely to get 1100 than 1300)

From a 1983 Hrercules loading manual (Pistol and Revolver loads page)
44 Magnum -- 240 grain lead gascheck Hercules 2400 18 grains = 1325FPS @ 34,300CUP
Blue dot 15 grains same same
Unique 12 grains same same

[Savvy Jack]

There was a concerted effort during the 1960's -70's to push velocities for the 44/40 to what I think were irresponsible levels, 2000 FPS loads showed in several loading manuals of that time - so do we maybe take the pressure figures from that era with a grain of salt ? or conclude they were crazy and figured things out after they blew a few guns up?

from the Aussie "Reloading Simplified 1973" - 200 grain jacketed -
Dupont 4227 - 29 grains = 2000FPS
ICI 2202 - 29 grains = 1995FPS
Nobels Revolver No1 27 grains = 2000FPS

in the suggested load column they drop two grains for 1850FPS

at the bottom blackpowder 33 grains is guessed at 1300FPS
(33gains of black more likely to get 1100 than 1300)

From a 1983 Hrercules loading manual (Pistol and Revolver loads page)
44 Magnum -- 240 grain lead gascheck Hercules 2400 18 grains = 1325FPS @ 34,300CUP
Blue dot 15 grains same same
Unique 12 grains same same

Sharpe's 1930's manuals shows 27.5gr of 2400, 2,100 fps @ 33,000 cup

Your "Irresponsible" goes back much further than the 1960's

In my tests, I recorded 1,735 fps @ 19,652 psi (well over 22,000 cup) with 26gr of IMR-4227 with a 200gr hard cast Acme Magma. My highest psi reading was 21,786 psi...could be close to 30,000 cup, using 12gr of Unique with the same bullet. Pistol powders are BAD medicine when loaded hot. No room for even a 1/2 a grain mistake.

This is my 44-40 test result data spanning only the past few years with the Pressuretrace II system. There are only a few pages of copied data from Lyman, Sharpe, John Kort etc. but it keeps me on my toes trying to remember where everything is located. I constantly have to search my own records to make sure I give correct data and not inadvertently mis-represent anything.

269104

[indian joe]

Sharpe's 1930's manuals shows 27.5gr of 2400, 2,100 fps @ 33,000 cup

Your "Irresponsible" goes back much further than the 1960's

In my tests, I recorded 1,735 fps @ 19,652 psi (well over 22,000 cup) with 26gr of IMR-4227 with a 200gr hard cast Acme Magma. My highest psi reading was 21,786 psi...could be close to 30,000 cup, using 12gr of Unique with the same bullet. Pistol powders are BAD medicine when loaded hot. No room for even a 1/2 a grain mistake.

hmmmm figured that one out the wrong way meself
357 magnum Rossi
38 special brass (some of it probably pretty tired)
RED DOT - dont remember the load but had transposed info across from 357 and 38 special pistol numbers using a 150 grain LEE round nose that I had clipped a flat point on so likely 145 grain
worked my way up, everything going ok, zero signs of trouble - fired a coupl hundred of those - got me a new mold, a 158 grain LEE flat point (my ideal mold for the 357 in a Rossi) proceeded to load those in the same cases, same powder charge, and it was still well under the 357 load - but we just added ten grains of lead and used up a little more case room - noticed a bit sticky extraction on about the fifth shot - number seven or eight - total case head separation !!! ok somebody else's worn out brass - get over it --but going back over the fired stuff the rifle chamber is a bit rough and every little mark is engraved into the outside of all those fired cases. No more RED DOT for this ole cowboy (got a heap of it too me father left it to me)

[Savvy Jack]

Also, your assumption of "I focussed on his "25 gr RE7 = about 23000psi for the comparison I made" - yeah cherrypicked that a bit !" is completely incorrect. That was the load of RL 7 tested which was in answer to the OPs question with the psi reduced by the amount based on the test results. That load of RL 7 under the 240 gr bullet produced 24,400 psi in the 44 magnum as tested. It should, therefore, produce 23,000 psi in the 44-40 as stated. No "cherry picking" involved at all.

I think it is 100% plausible for certain 240gr RL7 25gr loads to produce high velocities (20,000 psi) with certain "components". So far the difference between my 44-40 "components" and Larry's 44 Magnum "components" are too different to compare our tests to each other's but I think the theory he is working on has merit.

Even with my tests being consistent, variations are great depending on the design of the bullet used. Once you get into the 44 Magnum fairgrounds, things can go nuts. This is why I always get angry when folks accuse me of trying to make a 44-40 into a 44 Magnum, it can not be done. 44-40 is a 200gr to 220gr cartridge that works well with SOME 240gr loads. The 44 Magnum is a 240gr on up cartridge. A 44 Magnum with a 210gr bullet ain't a 44 MAGNUM <sarcasm>!

Compare these loads again

Reloder 7, Starline cases, CCI-300 primers, CL- 1.300". I do not use any case shorter then 1.300" with HV loads or loads not in manuals. Most 44-40 factory cases are 1.295 (per Lyman). Starline puts out 1.300 sometimes. I got lucky! Length also effects pressures. In order for the 44 Magnum tests to be compared to the 44-40 tests, all components must be the same in regards to bullet design, weight, bore, bullet diameter/hardness etc.

25gr/3D LRNFP/1,300fps/9,613 psi
25gr/ACME Hi-Tek SWC/1,420 fps/14,542 psi
25gr/SDCHP/1,350 fps/15,248 psi
25.3gr/Lee 3Crimp(forget name)/1,446 fps/15,279 psi


269103

[Savvy Jack]

hmmmm figured that one out the wrong way meself
357 magnum Rossi
38 special brass (some of it probably pretty tired)
RED DOT - dont remember the load but had transposed info across from 357 and 38 special pistol numbers using a 150 grain LEE round nose that I had clipped a flat point on so likely 145 grain
worked my way up, everything going ok, zero signs of trouble - fired a coupl hundred of those - got me a new mold, a 158 grain LEE flat point (my ideal mold for the 357 in a Rossi) proceeded to load those in the same cases, same powder charge, and it was still well under the 357 load - but we just added ten grains of lead and used up a little more case room - noticed a bit sticky extraction on about the fifth shot - number seven or eight - total case head separation !!! ok somebody else's worn out brass - get over it --but going back over the fired stuff the rifle chamber is a bit rough and every little mark is engraved into the outside of all those fired cases. No more RED DOT for this ole cowboy (got a heap of it too me father left it to me)


This stuff gives me a headache. It is absolutely NUTS!

I think a lot of hurt rifles that we see are because guys try to load them heavy with fast burning pistol powders like Bullseye and even Unique. I refuse to use anything faster than Unique because I am not secure in myself catching an accidental double charge of the stuff. I do use Unique in my revolvers because its best. I have used it my rifles but now I shoot longer distances so I use mid-range slower burning rifle powders.

Again from Sharp back in the 1930's


" The 44-40 is capable of excellent performance when loaded properly for handgun use. If, however, one endeavors to combine loading for both handgun and rifle in this caliber, he is destined to meet with only mediocre success. As in all other dual-purpose cartridges, the factory loads are only a compromise at best. Smokeless-powder loading for handguns requires a much more rapid-burning type than loading for rifle use, as the short barrel must burn all the powder if satisfactory results are to be achieved. In addition, rifle cartridges can be loaded to a pressure of about 30,000 pounds in this caliber, whereas the same load in a revolver would be more or less disastrous."