Folks, I know the 7th round stoppage problem was fixed after they discovered they cut too much off the receiver. This is what we commonly know as the 7th round stoppage for collectors and receivers that were cut and were not later welded up at the arsenal and remachined, are rather rare.
Having said that, a stock CAN cause a 7th round malfunction as well. This is very rare in a G.I. stock, but it can happen. It happens mostly with after market stocks. Further, it can happen from contact in one of three places.
The first place is in the relief cut on the stock for the bottom tail of the clip latch. The EMcF stocks and earlier stocks had an angle relief cut instead of the deep half round relief cuts that we are used to seeing as the arsenal changed the cut. As the stock wore, the tail of the clip latch would press against the wood (usually causing an indent there) and it would slightly alter the functioning of the rifle. It usually showed up more often at the 7th round, but it can show up sooner in the clip than that. Even with the latgr deep half round relief cuts, if the tail of the clip latch rubs and indents on the stock, it will cause the same thing. This is a problem with most commercial stocks. After shooting it for a while, you will see an indent from the tail of the clip latch. Clear/cut out JUST the wood that is indented and it should not happen at all or for a very
long time.
I've also seen indents in commercial stocks from such things as the follower arm cause this problem though that seems to have been pretty much corrected in the last 10 years or so. Bishop and some of the old Rheinhardt Fajen stocks had that problem where they didn't cut the large rounded relief cut in front of the stock well deep enough.
Now the third area sounds may sound more like voodoo than engineering and I'm well aware of that when I bring it up. Somewhere I read that the arsenal found out that if the receiver bore down (and indented the wood) between the rear of the receiver legs and back to 1 1/8 from the rear of the receiver heel (measured from the rear going forward), that this would also cause a 7th round or other malfunction. There is supposed to be just enough room between the top of the stock and the bottom of the receiver there that you can barely see light between the two. When the stock is correctly fitted, the receiver is actually bent down slightly between the forward bedding area and the bedding area around the rear of the receiver heel - when you tighten the trigger guard down. That keeps the rifle snug and accurate, but it also ensures it will function correctly. On MANY commercial stocks, I've seen indenting in that area where there should be no contact. What I do is use a flat file and draw file between the two points on top of the stock so there is the proper clearance where you can just see light. I actually did this again on a commercial stock at Camp Perry a week or so ago after checking timing of the receiver and just clearancing the stock corrected the function issues. Yeah, I'm sure this sounds like voodoo and I don't have an engineering explanation but I personally believe it has to do with the stresses put on the operating parts. For whatever reason, it works. HTH
to prefer its clips to be stacked one way or another? My rifle prefers for the ammo to be stacked "high right" in the clip. Some don't have a preference - this one does. I've had to re-stack clips that I had hand-stacked from high left to high right to get them to feed at all.
PM
Originally Posted by RCS
