25-20 case separation puzzler

[rickster]

Anyone seen this kind of separation before? I have had 4 case separations out of 50 rounds. Separations occur at the shoulder. I have loaded tens of thousands of rounds in 34 different calibers and have never seen this before. No harm done. The neck and shoulder just stay in the chamber after extraction. A bore brush easily gets the piece back out.

The cases have been fired over 10 times (maybe as much as 20). Have had no case head separations or split necks. Early loads were 20 to 25Ksi J loads. Since then 8 or ten with Meister 85gr cast. Cases failed while shooting with Meisters over a case full of Trail Boss. The reloads were fired in a well broken in Rem 25. Chamber looks fine.

[kelbro]

Never seen that but they are THIN cases to begin with. Possibly setting the shoulders back a little too far. ??? At least you know now where to check with the bent paperclip case separation inspection tool.

[Dale53]

This can happen with most any caliber when the shoulders are set back too far. This is generally the result of following directions that tell you to screw the full length sizing die until it contacts the shell holder. Some even go so far as to set it down until the press goes over top dead center. The Rem Model 25 is NOT a bolt action and probably has a bit of excessive headspace. It is certainly a "bit springy" compared to a strong mauser type bolt action.

I have loaded a 25/20 rather a lot in a modern Marlin lever action (very strong action for the round). You need to take a fired case, and just set the shoulder back barely enough to allow you to close the action. There should be just a bit of "feel" when you do it. That insures that you will not be setting the shoulder back too far. Over do that and you will be unable to properly lock up the action or put undue stress on it. Just barely "feel" the action closing on the case is the best I can describe. Then LOCK the die at that point and it should resolve the problem.

This is where a turret press like the Lee Classic Cast Turret allows you to set each individual die where it should be and just instantly swap out the die with settings already in place. The Dillon 550B works the same way as do the LnL set ups.

FWIW
Dale53

[rickster]

25-20 headspaces off the rim, not the shoulder. Not that a guy cant set the dies to headspace off the shoulder, but it is intended to HS off the rim. And even in similar cases in rifles with excess headspace (like in my Winch 43/218 Bee), case separation occurs at the web, in my experience. Maybe cast loads are different because of the lower pressures? I can see where that might cause the stress to occur farther up the case. Have you had a case separate at the shoulder?

[runfiverun]

mine usually give out at the bottom like the 303 and belted magnum cases do.
i have a friend who's cooper rifle in 223 splits cases at the top like that.

[Dale53]

rickster;
I guess you are directing your question to me. I have NOT had any case separations in 25/20. I am fully aware of where the case is supposed to headspace. However, it is common for belted cases (that are supposed to headspace on the belt but rarely do) to suffer from separated cases. The Rem 25 is a springy action (compared to a bolt action, as a comparison) and maybe, just maybe, the life of a twenty times reloaded case is normal (that is retire it after twenty reloads?).

My high speed load with a 70 gr gas checked bullet (cast of linotype) drives this bullet at just under 2200 fps. In my Marlin, (this is for a strong action which the modern Marlin is) I took five cases, loaded them at the range and fired them 20 times without losing a case. I've shot this rifle quite a bit in lever gun matches and never lost a case through loading (did ding up one or two through loading error). However, I have had no personal experience with the Rem 25 and it just may (through lack of strong lock up) suffer from limited case life.

That IS an unusual point for a case separation but without the rifle AND cases it is difficult to say WHAT the actual problem is. We are ALL just guessing here...

Dale53

[9.3X62AL]

What Dale said.

One 25-20 variant that is notorious for being "chambered long" are the 1988-1992 Marlin Model 1894CL. I got case seps much like your own after 4-6 firings of both WW and RP brass that had been full-length sized in FL sizers screwed down to lightly touch the shell holder. Now, I neck-size the brass in a 25 ACP sizer adjusted to size about 2/3 down the neck. Not only did this lengthen case life, it also tightened groups a bit.

[303Guy]

Rickster, could you post a picture of a fired case, a sized case and a loaded cartridge, please? Could you measure the shoulder/body junction for the three? A picture of the Meister boolit would be nice too. What is the seating depth - boolit base relative to the neck/shoulder? Do you crimp? How often do you anneal and how far down?

[Bret4207]

In addition to neck sizing, annealing often helps keep things from separating.

[atr]

I think Bret may have something going with his thought about annealing. If you have reloaded your cases as many times as you mentioned you probably have hardened the brass and annealing is necessary.

[StarMetal]

25-20 headspaces off the rim, not the shoulder. Not that a guy cant set the dies to headspace off the shoulder, but it is intended to HS off the rim. And even in similar cases in rifles with excess headspace (like in my Winch 43/218 Bee), case separation occurs at the web, in my experience. Maybe cast loads are different because of the lower pressures? I can see where that might cause the stress to occur farther up the case. Have you had a case separate at the shoulder?

You didn't pay attention to what Dale had to say. Yes we all know what rimmed center fire cartridges headspace off, I'll throw in belted magnums too. The knowledgeable reloader will reload all those to head space off the shoulder, that is if they are bottlenecked. Remember when the 30 and 357 Herrett was a hot item. Shooting them out of the Contenders? Lots of head separations until the savy learned to space off the shoulders.

Dale made good points and I like Brets annealing, although I would be careful doing that with such a short case.

Joe

[kelbro]

The brass is very thin and only takes a couple of seconds to anneal.

[rickster]

Dale (and others). Sorry to get under your skin there. I read your post late last night, took it as someone trying to give me kindergarten lessons in reloading and in my haste to get to bed, fired off a short and less than diplomatic response. Maybe what follows will help. It may not be any more agreeable, but at least it includes more information. And I have attached a series of pics.

A little clarification. The thrust of my original question was not to get a lesson in how to extend life cases via adjusting dies and annealing. I am perfectly content getting 20 reloads out of these 50 cases (1000 total), under the circumstances. Under other circumstances, I have 32-20 cases that have been annealed twice and are finally wearing out at over 50 reloads. The thrust of my question was to explore a type of case failure I had not seen before.

Regarding the case in question, I have two setups for reloading. One that uses dies set up to maximize life, using my pet loads. And one for experimentation. In the pic of the east end of my reloading bench you can see a gray and red Lyman turret press set up with 218Bee, 25-20, and 22Hornet dies. In the background is an orange 3 position Lyman press set up for 32-20. In another pic (if I can find it) an old 1976 Ford F250 is set up for field tests.

Time is at a premium when I am testing, so I usually don’t worry about getting the dies set up just right. There are some exceptions to this rule, in that there are some cases (e.g., 225 Win, 218 Bee, and 25 Rem) that must be carefully set up to get anything over 5 reloads. But typically, I reload fast and furious, with more than one gun (so they don’t overheat). When cases start giving out, they go in the grass, unless there is something unusual about them that I want to examine later. Part of this procedure is to see how long they will last, and where they will fail first. Most of the reloads on the 25-20 brass in question were (mis)treated this way.

Some data. The pics show a case that was blackened with a sharpy, and then resized. On either side is spent round and a loaded round. I didn’t get a pic of the case head, but the primer is not flattened or backed out. The pics also show using a 308 case being used to measure and compare shoulder setback. Using this method, a case full length sized with RCBS dies sets the shoulder back .004. A case full length sized in with Lee dies sets the shoulder back about .020. The Lee die is the one I used in the field. No doubt the .020 set back is the cause of the case failure.

Regarding pump actions. I reload for 6 lever actions, including a Marlin 1895 that I converted to a takedown. I don’t have an 1894 for reasons I can explain later, so I don’t have any first had experience with that rifle. I also have a dozen or so pumps. This one has no headspace issues. My own experience (lacking a 1894) relading for both levers and pumps is that lever actions stretch more than pumps because the lock up on a lever is at the rear and the lockup on a pump is at the front. Those may be fighting words. So be it. I will concede that pumps are harder on brass, because standard procedure is to full length size brass to be fed into a pump gun. This is to ensure reliable feeding, not because the receiver stretches. I happen to have a Rem 25 that was overloaded (not by me) to the point that the barrel swelled at the chamber, bowing the frame outward about .030. After examining the gun, I decided to rebuild it (for myself, it will never be for sale). I took the bow out of the receiver, and threaded and chambered an old Enfield barrel for in 32-20. It shoots like a dream, and I have lost count of how many thousands of rounds I have put through it with no problems. At one point I found a used 25-20 barrel. So I swapped barrels. The 25-20 barrel headspaced and indexed perfectly. Yes, I was surprised. At any rate, I personally have no concerns with the strength of the Rem 25 action. This may not be enough o convince everyone else, but that is OK by me. I will gladly take any Rem 25 that you are unhappy with.

Having said all that, the original question still remains (at least in my mind). Why did the case fail at the shoulder, and not at the web?

[Dale53]

rickster;
I mentioned that I know little about a Rem 25 pump gun regarding strength. I just mentioned the Marlin as I consider it a strong action (not as strong as a good Mauser style bolt action but strong nonetheless) to hopefully keep someone with a weak action from using high speed loads (a cast Ballard, for example).

I was NOT comparing a pump action to a lever action (I have no experience with a pump action).

However, I do understand the need for keeping enough headspace to easily operate a rifle, etc. "O" headspace sounds nice when reading about it but can cause operating problems.

To answer your last question, I have no idea why the case failed where it did. However, I offered a couple of suggestions as to possibly why. I still believe setting the shoulder back is the cause. Cases fail where they are the weakest or where the rifle (in this example) support them the least. A large chamber (typical in a lot of early examples of various types of actions) will cause an "abnormal" failure. Brass is ductile (as we all know) but it HAS it's limits. These cases have obviously exceeded that limit.

A chamber cast can rule out a large chamber (or confirm it). We have already discussed pushing the shoulder back, repeatedly.

It is obvious that you are NOT a newbie. I have not experienced ANY recent case separations and suspect that is because I set up my dies to minimize that happening. With my equipment, that is easy to do and only ONCE is necessary (that is NOT a statement of "superiority" but a statement of "what I do"...)

FWIW
Dale53

[StarMetal]

Not on answering the question, but I have a good friend in OK that had a 742 Remington in 30-06. For years he reloaded for it using a Lee hand loader, which you know only neck sizes the brass. He had zero problems...and shot some of the smallest groups I've seen from that type rifle. So much for small base dies or full length resizing at least in his rifle.

I do think one of the first steps to helping the brass have longer life it just neck sizing. Maybe you might try it in an action that normally stretches the brass just to see if it will digest them. If not you can also try partial full length resizing. You already know about annealing. Keeping your inside necks clean helps to as the expander doesn't grab it and pull on it. Another think are the bushing dies. Really not necessary to size the neck portion of a case down more then needed. Same goes to how much expanding it back out.

Joe

[Bret4207]

Rick, if you come across any more 25's needing a home, I'd be a willing adoptive parent. It could join my 2 Savage 23C's, the 23 B and Marlin 1894. The 32-20 case finds a willing home here in all it's guises- 32-20, 25-20 and 218 Bee.

I think you've got the problem identified. The shoulder is getting worked during sizing and shooting that's why they're cracking there. It's the only thing that makes sense to me.

[badgeredd]

Rick, if you come across any more 25's needing a home, I'd be a willing adoptive parent. It could join my 2 Savage 23C's, the 23 B and Marlin 1894. The 32-20 case finds a willing home here in all it's guises- 32-20, 25-20 and 218 Bee.

I think you've got the problem identified. The shoulder is getting worked during sizing and shooting that's why they're cracking there. It's the only thing that makes sense to me.

I agree Bret. I had a similar problem with the 218 Mashburn, before I segregated the brass from 2 different rifles. I neck size only and anneal after 5 loadings.

Edd

[35remington]

Here's my own take on it, for whatever it's worth:

It seems to me that the rim is headspacing the round as you load it, and there is some gap twixt the shoulder of the case and shoulder of the chamber. When fired, the case head near the rim doesn't have much room to go rearward or forward, as the rim recess in the chamber doesn't permit the cartridge to go forward very far under the firing pin blow, so it can't go backward very far to hit the bolt when the case head is hit by the pressure of the powder gasses. In theory, it's properly headspaced because the rim is doing an effective job. In practice, it's properly headspaced but poorly dimensioned for the chamber it's fired in.

If it can't go rearward very far when it is backstopped by the bolt face (and it can't go rearward very far and stretch the case near the head because it didn't go forward very far) then the most significant gap in regards to case conformity to the chamber is not near the head of the case, but near the shoulder due to the sizing method used.

It may be that since most of the gap or slop is near the shoulder, most of the stretching and thinning (or maybe the repeated working and work hardening of of the case walls just below the shoulder is a better term) of the case commences from that point nearest to the gap, which is the point where the case body grips. The neck grips on firing. The case body grips on firing. The head goes backwards only very slightly before it is stopped by the bolt face. The only thing that can move much is the case shoulder, and it's blown forward. In effect, you're fireforming the case shoulder forward on every shot. A few times is probably not noticeable at all.

Repeatedly makes the unsoundness of that practice apparent, and the brass may be worked excessively in that area, leading to its forming a weak point and eventual failure. It would make sense the case would fail near the area that is being worked the most, which is the shoulder area.*

When a case head separates near the head, it separates because it's being worked there. You're working the shoulder more than the head.

If your (Lee?) dies set the shoulder back as much as twenty thou, that's a lot. If you were headspacing on the shoulder in a rimless cartridge, that would be considered greatly excessive headspace artificially produced by the loader by the improper adjustment of the die. Having a rim masks the problem, but doesn't shield the brass near the case shoulder/chamber shoulder gap from repeated excessive working.

Now, what I just said may be a rehash, in some form, of what the other guys are thinking. It's just my way of putting it into text. For better or worse, I guess.

On edit: *Look at Dale's suggestion: "Cases fail where they are the weakest or where the rifle (in this example) support them the least."

Less support means more working of the brass. More working of the brass means failure at the worked area.

[rickster]

Sounds like we are in good agreement fellas. And 35 Rem, as usual, gets the prize.

Something I forgot to mention, is that I measured the OD of the shoulder before and after resizing. The change was only .003, or 1.5 thous per side. So I think we can rule out an enlarged chamber.

Oh, and a final thanks to Dale (and others), who prompted me to go to the trouble to measure the setback. I had expected some, but not .020. Discovering that much pretty much put the nail in the coffin.

[Bret4207]

Sounds like we are in good agreement fellas. And 35 Rem, as usual, gets the prize.

Something I forgot to mention, is that I measured the OD of the shoulder before and after resizing. The change was only .003, or 1.5 thous per side. So I think we can rule out an enlarged chamber. But how far is it moving front to back? Is the angle changed? Pretty hard to measure.

Oh, and a final thanks to Dale (and others), who prompted me to go to the trouble to measure the setback. I had expected some, but not .020. Discovering that much pretty much put the nail in the coffin.

Agreed.

[Dale53]

The important thing is, the cause has been determined and the "fix is in":mrgreen:.

Dale53

[pjogrinc]

In some of my research on the 25-20 SS, I have found several references to case streching if the case interior is not clean. Could you be having the same problem ?? I know in my WIN 1885 HW with original barrel/chamber, that if I do not clean the brass every 2 firings, that my case length grows, but only .002 to .003 inch. Don't know if this will help, but try it, it wont hurt.

[James Gibson]

why dose it look like they came apart at the annealing line? Could it be that after the annealing the neck and shoulder expanded and held in the chamber and the lower part was too hard to expand to the wall of chamber and it moved back and seperated.

[rickster]

I think that what might look like an annealing line is a smoke line from escaping gasses.

I put a few tack welds on the face of a 25-20 shell holder and then machined the welds back with a lathe so that I can run the case all the way in until the die bottoms out on the shell holder. That shell holder will be dedicated to the Lee die. Now I wont have to worry about whether the dies are adjusted just right. (Lee dies do not have a locking ring. Instead they have a nut with an oring. That’s fine if they can be left set up in a turret, but not so good if you frequently swap dies around like I do in the field.) The buildup on the shell holder face will effectively add .016 in to the length of the shell holder/die combo. So now the shoulder will only be pushed back and forth .004, instead of .020. That should give a good compromise between reliable function and case life.

I hadn’t thought of the effect of a clean/dirty case neck. Could have been a factor as well.

[StarMetal]

I think that what might look like an annealing line is a smoke line from escaping gasses.

I put a few tack welds on the face of a 25-20 shell holder and then machined the welds back with a lathe so that I can run the case all the way in until the die bottoms out on the shell holder. That shell holder will be dedicated to the Lee die. Now I wont have to worry about whether the dies are adjusted just right. (Lee dies do not have a locking ring. Instead they have a nut with an oring. That’s fine if they can be left set up in a turret, but not so good if you frequently swap dies around like I do in the field.) The buildup on the shell holder face will effectively add .016 in to the length of the shell holder/die combo. So now the shoulder will only be pushed back and forth .004, instead of .020. That should give a good compromise between reliable function and case life.

I hadn’t thought of the effect of a clean/dirty case neck. Could have been a factor as well.

Rickster,

That's a good idea. Kind of insurance and I like it. You might swap the lock ring out on your Lee die with one from say RCBS and not have to worry about that O ring. I understand what you are saying about constant swapping the dies out. One thing I don't like about the Lee die is when you have it screwed in tight in your press, watch as you size a case. It moves. Now whether that is a good or bad thing I haven't determined yet. Maybe you could think of it as self aligning and maybe that's good. But watch it next time you use one.

I hope that readjustment of sizing solves your problem

Joe

[9.3X62AL]

Good to hear that the problem was found and addressed.

Both 25-20 and 32-20 WCF chambers and dies are a little "poetic" in terms of dimensioning, in my experience. I have a Marlin Model 27-S slide action in 25-20 in need of some TLC in other ways, but its chamber specs are a LOT better than the far newer Model 94 levergun I discussed in my prior post. So much so, that as I continue the rebuild on the 27-S I will dedicate W-W brass sized for that rifle's chamber, and set aside the R-P for the levergun. No way to have "one size fits all" with those two chambers, and the levergun is likely a bit stronger than the century-old slider anyway.

[Baron von Trollwhack]

For my Classic "Long Chamber" .258 Boxer Central Fire aka 25-20 Marlin, I cured most all case/accuracy problems by (1) case forming from 32-20 brass, (2)less than fully neck sizing and annealing every third firing, (3) using a Lyman "M" die after sizing. I get darned good results, 3" @ 100 for 5 shots, 257420 or group buy. BvT