Cases sticking in chamber

[Dezynco]

I'm sure I know the answer to my problem, but I wonder what causes it.

I have a Contender barrel chambered in 7.62x39 (308 bore).  I have a batch of Winchester once-fired brass that I neck-sized and reloaded.  I'm having problems with about half of the brass sticking in the chamber.  This batch of brass is all from the same bag, I deliberately kept it all together to work up some hunting loads for this deer season.  When I say the brass is sticking, I mean the UNLOADED brass.  When I ran afoul of the problem with loaded cartridges, I went through my empties one at a time and found that about half of them will stick.

I cleaned the barrel and chamber very well to be sure that there was no gunk in there.  I'm pretty sure that a full-length resize will fix the problem, but I was hoping to neck-size only.

Any ideas what's causing this, I'm sure it's not the neck because, even though I cannot fire it, factory ammo will fit just fine, and factory ammo is usually .310 - .311 diameter.  My barrel is 308, so there's plenty of room in the neck area of the chamber.

What's causing the brass to stick?

[LaOtto222]

Could be a number of problems, but over pressure can be one of the the causes, an over sized chamber may be another. It is not unusual for brass sticking in a chamber of a break open rifle. If I had this problem and I was sure I was not getting an over pressure situation, I would just bump the shoulder back enough to chamber. You do this by backing off your full length sizing die at least one full turn and then taking a case that is over sized and run it into the die. then try to chamber it. Keep turning the die down 1/32" of a turn, run the case back in and trying the case. When it chambers OK, then try another one that is not going into the chamber. If it chambers OK, lock down your die. You are sizing just enough to chamber rounds. You are doing more than just neck sizing, but will extend case life, by not stretching enough to fill the chamber each time you fire the case and you will have the case nearly filling the chamber. Just make absolutely sure you are not getting over pressure to start with. A deer is not going to know the difference if you are getting 200 fps less, it will do the job just as well. Good Luck and Good Shooting

[Dezynco]

Thanks for the tip.  However what puzzles me is that these are once-fired empties that will not come out of the gun.  The first firing was with some very mild cast bullet loads.  The problem seems to be random.

I wonder if it's got anything to do with the quality of the brass.  I've thrown out a batch brass by this same manufacturer be cause I was having the same problems.  I just thought the brass was worn out.

[Graybeard]

I might be wrong but I don't think the 7.62x39 is a proper fit for the Contender. I thought that was an Encore only type round. I suspect it's too much pressure for the Contender platform that's at fault.

[Sensai]

The first firing was with some very mild cast bullet loads.

This MAY be your problem.  With very mild rounds the pressure doesn't build rapidly enough to really hold the cartridge walls to the chamber walls.  The cartridge sets completely back to the breech/bolt face before it is fully expanded.  This results in the maximum sizing for a "fire formed" cartridge in that particular chamber.

If I had this problem, I would full length resize the cases once.  Load them with my normal load.  Fire this loading.  Check the chamber fit after this firing.

I think that the chamber fit will be fine, and you can start neck sizing these cases.  I would be sure to check the case lenght, it may have streched after having the shoulder moved twice.

[LaOtto222]

Bill - I think you are correct. The 7.62X39 is not listed in the T/C custom shop as an option. My guess it the round is way too hot for the wall thickness of the Contender barrel + too much pressure on the breech face - thus causing sticking cases.

[Dezynco]

You guys are right about the 7.62x39 being too hot for the Contender.  The 7.62x39 WAY too hot with factory ammo, but it's fine for the handloader.  Bullberry specifically advertises this barrel for "handloading only", absolutely no factory ammo in their Contender barrel.  Given that, it's a very accurate little cartridge, but you might as well consider it a wildcat.

The bit about the mild cast bullet loads makes perfect sense in that the cartridge is pushing all the way back into the breach face.  I full-length resized the cases and everything is good now.  Had to borrow my old man's dies, I only have a neck-size die.