garand spent cartridge question

ajmaudio · May 15, 2010, 05:23 AM

starting to get more serious about shooting and just started reloading... due to this I am paying much more attention to my cases and such. I have noticed that the spent cartridges from my garand are expanded slightly out of round. I'll try and explain:
the part of the case that expands notably near the case head is biviously expanded more to one side than the other. total expansion in comparison to the far head end of the case is about 5 thousandths and within case spec at .469-.470 ... the far head end measures .464-.465
It would seem that the bolt/chamber are not centered perhaps?? most of this expansion is to the one side... Just wanted input as to the safety or normalness of this behavior in this particular firearm. the gun shoots great and fyi this behavior is similar between reloads and factory ammo.
Thanks

ogree · May 15, 2010, 06:05 AM

There is a possibilty that the back end of the chamber was cut slightly oval and that could be leading to the problem you are having.
It is quite rare for this to happen, I have only come across one rifle that had this problem, it comes from the barrel not running true (excessive run-out) in the chuck while the chamber is being cut.
Usually a little run-out will just cause the chamber to be slightly oversize and remain round as it should be.
As long as the headspace is correct you shouldn't have any safety issues with it the way it is, the rifle I saw with this problem that I mentioned earlier is still in use today with the barrel unaltered.
It will probably put a tiny bit more stress on the brass and slightly shorten the life of it.

dahermit · May 15, 2010, 07:13 AM

If you observe, almost all rifle spent cartridge cases will expand more on one side. My understanding is as follows: The cartridge must be smaller in diameter than the chamber to enable it to enter the chamber. It comes to rest on the bottom of the chamber with any clearance on the top. When it fires, it expands in the direction of the clearance to fit the chamber leaving the solid head slightly off-set from the body of the expanded case.

Rifleman1776 · May 15, 2010, 07:33 AM

These are very old guns, wear of the chamber is a possibility.
Resizing dies will fix it. I don't see a problem. But do clean and inspect carefully. For reloading, the old issue ammo can be reloaded nearly indefinitely, in my experience. I stopped counting many years ago.

ajmaudio · May 15, 2010, 05:00 PM

I did indeed notice that the old military brass seems to hold up better. I need to get my hands on more of it. Most of my reloaded brass in Win. It never ceases to amaze me that teh human eye and finger can detect such small bumps etc.. I mean.. .005 is small and yet it is easy to feel.

May 15, 2010, 05:23 AM	#1
ajmaudio Member Join Date: April 27, 2010 Posts: 19	garand spent cartridge question starting to get more serious about shooting and just started reloading... due to this I am paying much more attention to my cases and such. I have noticed that the spent cartridges from my garand are expanded slightly out of round. I'll try and explain: the part of the case that expands notably near the case head is biviously expanded more to one side than the other. total expansion in comparison to the far head end of the case is about 5 thousandths and within case spec at .469-.470 ... the far head end measures .464-.465 It would seem that the bolt/chamber are not centered perhaps?? most of this expansion is to the one side... Just wanted input as to the safety or normalness of this behavior in this particular firearm. the gun shoots great and fyi this behavior is similar between reloads and factory ammo. Thanks

May 15, 2010, 06:05 AM	#2
ogree Senior Member Join Date: January 18, 2005 Location: Idaho Posts: 151	There is a possibilty that the back end of the chamber was cut slightly oval and that could be leading to the problem you are having. It is quite rare for this to happen, I have only come across one rifle that had this problem, it comes from the barrel not running true (excessive run-out) in the chuck while the chamber is being cut. Usually a little run-out will just cause the chamber to be slightly oversize and remain round as it should be. As long as the headspace is correct you shouldn't have any safety issues with it the way it is, the rifle I saw with this problem that I mentioned earlier is still in use today with the barrel unaltered. It will probably put a tiny bit more stress on the brass and slightly shorten the life of it.

May 15, 2010, 07:13 AM	#3
dahermit Senior Member Join Date: October 28, 2006 Location: South Central Michigan...near Posts: 6,501	If you observe, almost all rifle spent cartridge cases will expand more on one side. My understanding is as follows: The cartridge must be smaller in diameter than the chamber to enable it to enter the chamber. It comes to rest on the bottom of the chamber with any clearance on the top. When it fires, it expands in the direction of the clearance to fit the chamber leaving the solid head slightly off-set from the body of the expanded case.

May 15, 2010, 07:33 AM	#4
Rifleman1776 Senior Member Join Date: April 25, 2010 Location: Arkansas Posts: 3,309	These are very old guns, wear of the chamber is a possibility. Resizing dies will fix it. I don't see a problem. But do clean and inspect carefully. For reloading, the old issue ammo can be reloaded nearly indefinitely, in my experience. I stopped counting many years ago.

May 15, 2010, 05:00 PM	#5
ajmaudio Member Join Date: April 27, 2010 Posts: 19	I did indeed notice that the old military brass seems to hold up better. I need to get my hands on more of it. Most of my reloaded brass in Win. It never ceases to amaze me that teh human eye and finger can detect such small bumps etc.. I mean.. .005 is small and yet it is easy to feel.