What sort of pressures are our old-style cases built for?

[earlmck]

On another thread we were discussing loads to achieve moderately high velocity with a really fast-burning powder (Titegroup) in the old 44/40 case chambered in a Rossi rifle. So here we have a model 92-style rifle made of modern steel, so well able to handle pressures up toward the 50K psi range.

I poked some figures into the old ballistic program "QuickLoad" and allowed as how you could get the desired velocity level using Titegroup without unduly straining a Rossi rifle, though you wouldn't want the load to even sit next to an old Colt or Win '73 for fear of damage, as you'd be up around 40K psi.

Fellow Levergunner w30wcf provided data for a couple of his satisfactory 44/40 handloads but noted that the heavier load gave very short case life with incipient head-separations showing up. I ran his heavy load through QuickLoad and got an estimated 30K psi for the load.

And I also have a "favorite" load in Win '92 25/20 that gives those incipient head-separations after just a few shots. Had long blamed the rifle for "excess headspace" even though all my normal headspace remedies had not helped the head-separation issue. I just "tested" this load out in QuickLoad and old QL thinks I am in the upper 30K's with the load.

Now a couple of years ago I picked up a Browning in 218 Bee from Levergunner mod71alaska and then Bee brass from BlaineG. And you know what? -- that Bee brass, which is intended for a cartridge generating in upper 40K's pressure range, is about 20% heavier than my 25/20 or 32/20 cases, which are externally the same basic case as you know. The extra beef in the Bee case appears to be in the web area. And indeed, if I convert a Bee case to 25/20 I don't get case head separations (yeah, I tested one case thusly) though I also can't get the same amount of powder in the Bee case as I get in the 25/20 case (both Winchester brand cases by the way).

So my thought is that us fellows shooting the stoutly built model '92s and modern copies thereof may need to pay more attention to the pressure levels our brass is built for than what our rifles are built for. And maybe keep loads under 30K psi even though our rifles don't even know a round has fired until they start seeing pressures up toward 50K psi.

Here I will admit that this sort of consideration did not even enter my brain pan until this very year of 2014 when I happened to notice the great difference in brass mass between the 218 Bee case and the 25/20 case.

I'm having this suspicion that I'm the last guy here to pick up on this brass/pressure deal, though I don't recall another discussion of it on the forum. So is that the case? Is old earlmck the last one here to maybe figure this out?

[Canuck Bob]

Unless plaqued with case stretching from shoulder setback I rarely hear of problems. I have a 22 Hornet, 32-20, and find them strong enough. They are prone to shoulder collapse however. I might add I've never approached 50Kpsi.

Shoulder location seems the greatest threat to brass. My 32 Special isn't too bad but my 303 is really something. The early lever cartridges had long necks and short chamber necks. I often wonder if this is about shooting ammo prone to fouling or in trenches. I once thought it was not an issue because of the rims, wrong!

I do inspect with a bent wire to find any cases with an internal weak spot. It seems I focus on mid range power too. I want my brass to last and last!

[Carlsen Highway]

A timely meditation on pressure and brass cases, coming as it does at the same time I am reloading and about to test some more .44/40 HV loads.

[M. M. Wright]

At one point I had a Tigre, the spanish copy of the '92. It was very nice internally with a beautiful bore and gave pretty good accuracy. I never "hot rodded" loads for it but mostly shot it with cowboy loads even used for competition for the first couple of years that I competed. It didn't take very long for the bolt to start hanging out past the frame at the back. It just battered itself into a head space problem. Primers started to protrude enough to feel and then to see. I was using mostly 231 in the 44-40, (I've never seen a Tigre in another caliber) so this quick burning powder may have been the culprit though I'm thinking the problem was mostly soft steel. I guess in this case the rifle was not built for the pressures but the brass was good enough to keep me from hurting myself.

[Nate Kiowa Jones]

At one point I had a Tigre, the spanish copy of the '92. It was very nice internally with a beautiful bore and gave pretty good accuracy. I never "hot rodded" loads for it but mostly shot it with cowboy loads even used for competition for the first couple of years that I competed. It didn't take very long for the bolt to start hanging out past the frame at the back. It just battered itself into a head space problem. Primers started to protrude enough to feel and then to see. I was using mostly 231 in the 44-40, (I've never seen a Tigre in another caliber) so this quick burning powder may have been the culprit though I'm thinking the problem was mostly soft steel. I guess in this case the rifle was not built for the pressures but the brass was good enough to keep me from hurting myself.

I too would say it is the metal. The spanish made El Tigre was made in the 30's so it was probably poor metal. Even here in the USA we didn't really have good metal or at least good hardening techniques until after WWI.
The main problem with the old BP era bottlenecks is the thin brass. It just stretches too easy. There were express loads offered for the 92's not to be used in the 73's or revolvers, but I don't know what the pressure levels were for those.

[Old Savage]

Well, new to the 25-20, I was not aware of this issue. Thanks for the info.

[earlmck]

Well, new to the 25-20, I was not aware of this issue. Thanks for the info.

I'm not sure what info has been provided so far, OS. The old 25/20 was one of the first cartridges I reloaded for, back when I was just a squirt. But I had read lots of stuff on loading and I knew you started low and "worked up" until you got sticky extraction and then backed off a bit. But I ran out of room in the case before I got sticky extraction, though I got an occasional "pierced primer" (because the firing pin was a little too long, don't you think? ) So I have shot quite a lot of rounds made up of the Lyman 257312 bullet (about 90 grains) pushed by 11.5 grains of 4227 (either Hodgdon or IMR depending on what I found to buy).

I never chronographed that load but I can tell you that it will really thump a jackrabbit. Running it through QuickLoad shows it probably gives me over 2000 fps with that bullet and about 40K psi. Most of my shooting has been with an old black-powder era model 92 and that big old black-powder style firing pin and pin hole are where I get the pierced primers if I use something other than a Remington primer. Brass life has always been short -- head separations showing up after anywhere from 5 to 10 firings; but more likely the 5.

In the future I will work up loads with more attention to accuracy and I'll bet I come up with something more in the 1600 to 1800 fps range with the gas check bullet and nicely below 30K psi and cases may last long enough that I need to watch for neck splits.

Now if this Winchester had been made from metal as soft as that Tigre model that M.M. Wright tells us about I would have developed great headspace problems long ago, but I don't think the Winchester has been particularly bothered by these 40K psi loads. I have made cases from 32/20 brass, just sizing down enough to make a firm fit in the action, and get the same poor case life. Only now after 50 years of shooting that particular load, am I finally suspecting that life might be smoother if I could manage to leave out a grain or two of powder. Been a while since I shot my 25/20's but I have a batch of grandkids who might like give 'em a try.

Too bad jackrabbits are extinct in Central Oregon: I don't know if it is legal to shoot a 25/20 at any lesser target.

[Old Savage]

Earl, I was referring to your info regarding the brass and pressures. Except for a very brief experience for a friend's rifle this is the last thing I have gotten into after 25 yrs reloading.

[Old Ironsights]

Can't speak to old-time cases, but here's what a "modern" balloon-head case will do under excessive pressure...





Blew the extractor right off (Marlin 1895 type).

Easy fix, but... that kind of load needs Brass Hulls or .444 donor brass with a real web & solid head...

[w30wcf]

earlmck,

By the late 1890's Balloon head cases were the solid head type and were known as the SHBP (Solid Head Button Pocket) type. Prior to that they were the folded head type and certainly weaker.

When the WHV (Winchester High Velocity) cartridges were introduced in 1903 they were loaded in the SHBP cases. Pressures of the .45-70, .45-90 & 50-110 WHV cartridges were said to be in the 25,000-28,000 PSI range. They certainly survived one firing but I don't know how many reloads at those levels the cases would withstand.

Old Ironsights,
Ouch! Looks like that case was primed with a shotgun primer.

w30wcf

[Bill in Oregon]

This is a fine thread, Earl. I'll admit to having assumed that if the case had a solid head all the pressure considerations then fell upon the gun and its chamber. But if you neck sizing to avoid shoulder setback and headspacing on the shoulder -- and still having short case life -- the brass itself had to take a portion of the blame. I had no idea .218 Bee brass is so much stronger than .25-20. I know that .225 Winchester brass has this reputation, which is why J. D. Jones liked it for several of his wildcats.
This can go the other way too. I remember the late gunwriter Bob Milek, otherwise a very common-sense guy, dismissed the .45 Colt as a handgun deer cartridge beyond 50 yards because the "case wasn't designed for high pressures."

[Old Ironsights]

... Old Ironsights, Ouch! Looks like that case was primed with a shotgun primer.

w30wcf

Needed to be, since it was a .410 hull and I was working up a slug load...

[earlmck]

This is a fine thread, Earl. I'll admit to having assumed that if the case had a solid head all the pressure considerations then fell upon the gun and its chamber. But if you neck sizing to avoid shoulder setback and headspacing on the shoulder -- and still having short case life -- the brass itself had to take a portion of the blame. I had no idea .218 Bee brass is so much stronger than .25-20. I know that .225 Winchester brass has this reputation, which is why J. D. Jones liked it for several of his wildcats.
This can go the other way too. I remember the late gunwriter Bob Milek, otherwise a very common-sense guy, dismissed the .45 Colt as a handgun deer cartridge beyond 50 yards because the "case wasn't designed for high pressures."

Yes, I have been exactly in there with you Bill, in assuming a solid head case was a solid head case even if it was relatively thin-walled like our 44/40 cases or 25/20 & 32/20 cases. 45 Colt cases (at least the ones I posess) are not thin-walled and my 45 cases that I shoot in my Rossi 454 do not appear less substantial than the 454 cases I have, though I don't own any that are the same brand in both cases. I know the early 454 Casull developers did not seem to have any trouble running pressures waaay up there in the 45 Colt cases they were using at the time, so old Bob Milek was (I believe) wrong. Though he must have been way ahead of me in realizing that some solid head cases are not built to handle as much pressure as others.

I remember some while back in a thread on 32/20 (or maybe 25/20) fellow levergunner Sixgun made a comment about a load, saying it would have short case life. Which I though funny at the time as it was not what I would have considered "hot" for a strong rifle. But if we are needing to pay more attention to pressures -- if our thin-type cases truly do not handle the pressure that the thicker cases handle -- I am going to have to re-think my pre-conceptions.

I used to think I understood the physics behind case-head separations, and that it was only a phenomenon of guns having excess headspace problems. Maybe I was not totally correct?

[earlmck]

Shoulder location seems the greatest threat to brass. My 32 Special isn't too bad but my 303 is really something. The early lever cartridges had long necks and short chamber necks. I often wonder if this is about shooting ammo prone to fouling or in trenches. I once thought it was not an issue because of the rims, wrong!

I do inspect with a bent wire to find any cases with an internal weak spot. It seems I focus on mid range power too. I want my brass to last and last!

Bob, it sounds like you have made some very interesting observations on brass life, having to do with head separations. Back in my early reloading career I was involved with loading for a friend's Enfield 303. This was a sniper version and very accurate but we were getting head separations after only a few loads. Later on in life I have looked back on that and thought that I now knew enough about headspace and fitting the cartridge to the rifle that I could have solved our head separation problems. But your comment makes me wonder: is the 303 British case built or designed in such a manner that poor case life just naturally comes if you load to the mid- to upper 40K psi level the rifle is designed for? Even with a properly headspaced rifle?

[AJMD429]

I know the early 454 Casull developers did not seem to have any trouble running pressures waaay up there in the 45 Colt cases they were using at the time, so old Bob Milek was (I believe) wrong.

One thing there was I think (could be wrong) that the 454 Casull chamber is really on the 'snug' side vs. the typical SAAMI spec 45 Colt chamber.

• http://www.saami.org/PubResources/CC_Dr ... 20Colt.pdf
  http://www.saami.org/PubResources/CC_Dr ... Casull.pdf

Dunno if that is enough to matter...

[Carlsen Highway]

Shoulder location seems the greatest threat to brass. My 32 Special isn't too bad but my 303 is really something. The early lever cartridges had long necks and short chamber necks. I often wonder if this is about shooting ammo prone to fouling or in trenches. I once thought it was not an issue because of the rims, wrong!

I do inspect with a bent wire to find any cases with an internal weak spot. It seems I focus on mid range power too. I want my brass to last and last!

Bob, it sounds like you have made some very interesting observations on brass life, having to do with head separations. Back in my early reloading career I was involved with loading for a friend's Enfield 303. This was a sniper version and very accurate but we were getting head separations after only a few loads. Later on in life I have looked back on that and thought that I now knew enough about headspace and fitting the cartridge to the rifle that I could have solved our head separation problems. But your comment makes me wonder: is the 303 British case built or designed in such a manner that poor case life just naturally comes if you load to the mid- to upper 40K psi level the rifle is designed for? Even with a properly headspaced rifle?

Earl, the .303 headspaces on the rim. The problems with brass life are usually over rifles having generous chamber dimensions by design, which can be beat to a certain point by neck sizing brass. I dont believe the brass itself is weak. With a .303 Lee Enfield, your best friend is a lee loader hand tool.

[Larkbill]

"The problems with brass life are usually over rifles having generous chamber dimensions by design"

This.

In my son's Savage built No3 Mk1 fired cases are noticeably bigger than unfired. We have always neck sized only and so far cases are holding up well. Though we only use them for full power hunting loads twice (three counting original firing) then only use for cast loads.

Was the generous chamber perhaps necessary to ensure chambering of ammo from numerous sources of uncertain quality?