25-20 cases and reloading

[Marvin S]

I shot My new/old Marlin 27S for the first time yesterday useing new Rem cases. I shot about 20 rounds and noticed that two of the cases split just above the head. So im thinking something is maybe wrong with the chamber.
I get home and examine the chamber and measure the best I can with a telescoping bore guage and so far it looks okay. Then I get to looking at case dimentions in several manuals and find that case head measurement vary from .347 to .349. My Rem case heads measure .343 and that is what the LEE die sizes them back to.
The Rifle is in very good condition overall and looks to have been not fired in the last 50 years and the bolt locks up tight. I may try a chamber cast next.
Any other thoughts guys. I did measure the fired case at the split and it is .350.

[runfiverun]

case head separation is a way of life with the 25-20.
you just gtta watch for it and be ready to toss those spensive little buggars.
you could try to have a die opened, but it's just the way they are.
also use a good flair on the case mouth before seating.

[Marvin S]

These are splitting length wise. Is this commom also? Maybe too much head space?

[DLCTEX]

I believe that excessive head space will cause case separation, not longitudinal splits. I would check for an oversized chamber (measure a fired case) and try different brass, you may have a bad batch. Also check a resized case to see if the sizing die is undersized. For what it's worth, I've never had a case head separation in 22-250 in 30+ years of reloading for it. Lots of split necks after many reloadings, but then I don't load to the max.

[Dale53]

I have a modern Marlin lever action in .25/20. We used to have lever action matches at our club, so it got shot a LOT. I used the Lyman 257420 GC bullet cast of linotype and shot a full load (2100+ fps) and NEVER lost a case. I had a good number of cases. Just to check for case life with the full load, I loaded five cases at the range and kept shooting them. After 20 reloads, with NO case loss, I tired of the activity and quit.

I assume I had a good chamber and good brass. Every now and then you can get a bad lot of cases, but I have been lucky. I have had excellent results with Winchester .25/20 brass.

If I were ordering new cases, they would be Winchester simply because of my experience with this brass.

The two most likely cause of split cases would be a oversize chamber or a bad lot of brass. Occasionally, I have found a die that oversizes brass, but seldom to the extent that it causes split cases.

I suggest you make a chamber cast and determine the condition of your chamber.

FWIW
Dale53

[Marvin S]

I'm not finding any empty cases other than Remington.

[Green Frog]

Marvin,

If they are new cases (as I now reread that you say) I would suggest you may have a very loose chamber. If it is a brass problem, you can eliminate a lot of the problem with neck sizing instead of full length.

Froggie

[Dale53]

Here is some Winchester brass at Buffalo Arms:

http://www.buffaloarms.com/browse.cfm/4,73.html

Dale53

P.S. Hi Froggie! rdm

[atr]

Marvin,
I reload 25-20 for a Savage model 23B...and I use Remington brass...Ive never had any splitting or case head separation. I think the suggestion that you only size the neck is a good one, as is taking a cast of your chamber. And I wouldn't ignore the suggestion that you have a batch of bad brass. Generally speaking the 25-20 is a pretty forgiving cartridge to reload.
Let us all know what you discover.
thanks
atr

[Marvin S]

Ive had none of these problems with my 27S in 32-20. I will pour a cast maybe tommorow but dont really know what to use as a standard. Could some one measure the head dia of their Winchester cases for me. Thanks for the tip on Win cases at Buffalo Arm.

[Leftoverdj]

Longitudinal splits neat the base are very bad, Tell Remington about it. Maybe you'll get some replacement brass out of it.

Neck splits are very common and nothing to worry about, just toss them when it happens. It's especially common in brass with some age on it, even if they have never been fired.

[Bret4207]

If the dies are overly sizing the cases an option may be to use a neck sizing die.

[Marvin S]

The dies are sizeing them back to the original head dia of the Remington cases. If the cases where made to what the Accurate loading manual says they are supposed to be I dont think it would be a problem.

[runfiverun]

short size them then, just the first 1/4" of the neck,enough to hold your boolit securly.
use an universal primer punch if necessary.

[Marvin S]

Just poured a chamber cast and done some measureing. After full length sizeing, the cases are .010 smaller than the chamber at the head/main body area. I have a universal decapper that I use on my 38-55 32-40 and such. After I fire form the rest of em ill try just neck sizeing. Also plan on ordering some Winchester cases and trying them. The main reason I buy Remingtons in 32-20 is they are longer than the Win cases. Sure hope something works for this fine rifle, besides I have a lot of money in it not to mention the new Marbles tang sight.

[Dale53]

MarvinS;
Die instructions shipped by most all of the manufacturers do not tell the whole story. Lever action rifles do not have the camming power of a Mauser style bolt action. Partial sizing of the case can lead to all sorts of problems in a lever action if it is done blindly.

Head separations are often caused by setting the shoulder back too far on each reloading. The shoulder gets blown forward when the round is fired and eventually (two or three reloads) the head separates. This is solved by NOT setting the full length die hard against the shell holder. The proper way to do it is to take a fired case, back the full length die out a couple of turns, size the case. Then try the case in the rifle and keep moving the sizing die towards the shell holder just a bit at a time until you have just the smallest bit of "feel" when you close the action. You want to leave the shoulder of the case forward enough to feel when you close the action. Too much "feel" and the action will not close properly. By having "feel" when you close the action you have insured that the shoulder has not been pushed too far to the rear upon sizing. This even works with rifles that have moderately "too much" headspace.

Splits on the side of the case are caused from either of two things. Either the chamber is oversize or it is a bad lot of brass. It is possible that this can be aggravated by excessive headspace (often caused in old rifles by set back of the locking system caused by wear or excessive pressures).

The easiest way to check this out is to change the lot and brand of cases. If the new cases work well, then you have found the problem. If the new cases split, then it is undoubtedly a rifle problem.

Partial sizing or neck sizing in a lever action can lead to lengthening of the case head to shoulder dimension interferring with closing of the action. The solution there is to look at paragraph two above. Bolt action bench rest shooters often neck size. After a few times they have to re-size the cases to set the shoulder back. They do it by the "feel" method (they actually have a separate die set up and when they feel it happening, they go to the full length die and reset the shoulder). However, since you have a lever action (and I have great respect for a good lever action) you must be more vigilant - you don't have the camming power to overcome a "too long to the shoulder case", so you can be stuck with a bunch of loaded rounds that won't allow you to close the action all the way. Using the "feel" method when partial sizing has worked well for me in the past.

Good luck and keep us posted of your progress.

Dale53

[atr]

Marvin,,
here is what I measured from a fired case from a Savage model 23B
hope it helps.
excuse the pathetic drawing
atr

taken on a Win Super-X case

[BerdanIII]

You might want to try partially resizing .32-20 cases to fit your .25-20 using the technique described by Dale 53. According to SAAMI (not much help on older guns, I agree) the .32-20 WCF case is about 0.351" just above the rim. You may have to watch the length of the reformed cases, but I'd be willing to bet the chamber is over standard length.

I got this idea from an early Fouling Shot.

[beagle]

I have a Marlin M1894 .25-20 and a 24" Douglas barrel that I replaced the factory barrel with. I have had no problems with head seperation with R-P cases.

A friend gave me a bag full of cases fired in his Model 27s and I did get a lot of head seperations with some of the Winchester brass in that lot so the Model 27S may be prone to developing headspace problems. About a box of .218 Bee cases in that vbatch was fireformed and I haven't had any problems with them so I'm thinking he had headspace problems in the M27S.

I always neck size my brass and have had no chambering problems.

As has been suggested, neck size and see if the problem don't either go away or get a lot better./beagle

[Marvin S]

Thanks for all of the imput guys, I will approach this with all thoughts considered.
ATR is that a Win or Remington case?