Armory Sponsor
Posted: 10/16/2012 5:46:49 AM EDT
| Seems I remember Bench Rest shooters neck sizing only. Can this be done for an AR? I have new Fed LC 12 ammo. |
| To elaborate on what was already said the reason you can't neck size only brass for use in an auto-loading rifle is the case shoulders will expand upon firing and will not properly fit the chamber unless pushed back. You "could" do it, but you will have feeding issues and rounds will not properly chamber. From a reliability standpoint it would not be in your best interest. The chambers on bench-rest rifles and bolt guns are much tighter than the 5.56 chamber and the shoulders do not expand as much. This is why you can do it in bolt guns. Hope this helps. |
|
First of all I agree with the posts before mine. But like with most things in this world there are exceptions. In the case of your AR I too would say you would most likely get poor results for the reasons stated by the others.
BUT: For the record I routinely shoot neck only sized brass from my 49-56 MAS auto loading rifle. My brass is on it's 4th cycle and still works fine. I do however test chamber every one before loading them. Just lucky I guess. 
|
|
If you are reloading cases that were fired from a given rifle to be used again in the same rifle (or one with a more generous chamber) you could likely get away with less than full length sizing. By that I mean the sized case wouldn't necessarily have to fit a case gauge as long as it easily chambers in the rifle in question. In my opinion, as long as the neack is sized and the shoulder is slightly bumped back, the case should work fine. I would still use a FL die, but it could be adjusted to less than full length setting.
I know of older guys who have hunted for years with military rifles sporterized back in the '50's that have excessive headspace and they load fireformed cases that are for that rifle only. Their rounds will probably not fit other rifles of the same caliber, but the rifle is still servicable as long as factory ammo is not used in it. |
|
Quoted:
If you are reloading cases that were fired from a given rifle to be used again in the same rifle (or one with a more generous chamber) you could likely get away with less than full length sizing. By that I mean the sized case wouldn't necessarily have to fit a case gauge as long as it easily chambers in the rifle in question. In my opinion, as long as the neack is sized and the shoulder is slightly bumped back, the case should work fine. I would still use a FL die, but it could be adjusted to less than full length setting. I know of older guys who have hunted for years with military rifles sporterized back in the '50's that have excessive headspace and they load fireformed cases that are for that rifle only. Their rounds will probably not fit other rifles of the same caliber, but the rifle is still servicable as long as factory ammo is not used in it. Neck sizing is neck sizing! Any sizing that contacts the case body or bumps the shoulder back is NOT neck sizing. By definition, you are not "neck sizing " if you bump the shoulder back. The OP asked about "Neck sizing" , not Partial Neck sizing or Partial Full Length sizing. |
|
Quoted:
Seems I remember Bench Rest shooters neck sizing only. Can this be done for an AR? I have new Fed LC 12 ammo. Most BR folks F/L size now, and as noted, its not a good plan for an autoloading riflle anyway. From an accuracy perspective, F/L sizing with a good fitting die is the way to go, even for BR and F-Class bolt rifles. |
|
Quoted:
Quoted:
If you are reloading cases that were fired from a given rifle to be used again in the same rifle (or one with a more generous chamber) you could likely get away with less than full length sizing. By that I mean the sized case wouldn't necessarily have to fit a case gauge as long as it easily chambers in the rifle in question. In my opinion, as long as the neack is sized and the shoulder is slightly bumped back, the case should work fine. I would still use a FL die, but it could be adjusted to less than full length setting. I know of older guys who have hunted for years with military rifles sporterized back in the '50's that have excessive headspace and they load fireformed cases that are for that rifle only. Their rounds will probably not fit other rifles of the same caliber, but the rifle is still servicable as long as factory ammo is not used in it. Neck sizing is neck sizing! Any sizing that contacts the case body or bumps the shoulder back is NOT neck sizing. By definition, you are not "neck sizing " if you bump the shoulder back. The OP asked about "Neck sizing" , not Partial Neck sizing or Partial Full Length sizing. Thank you. I stand corrected. |
|
It is not just the chamber dimensions, but an autoloader extracts the brass while it is still under pressure. IIRC the port pressure on an M-14 is 14,0000 PSI which means there is 14,000 PSI in the empty shell casing as the action is opening.
I test-fired a FAL rifle I assembled for a friend recently and initially had the gas system set on G, which disables the gas system and keeps the brass in the chamber after the gun is fired. I then turned it to A, which is semi-auto. The single-shot brass fit in a chamber gauge, and the others did not. |
Armory Sponsor