Right.
If my problem had been that every round had exhibited the same issue, I’d probably have started by measuring the steel cased ammunition (or just throwing it out altogether). When I noticed that the problem only occurred after a certain number of rounds (more or less, about 50 rounds or so), regardless of any other factors, then I knew that it had to be a result of some condition changing with the gun.
When my buddy stated it was a dirty chamber issue and suggested I run a brass round every so often, I almost dismissed it as being “too simple”, therefore ignoring Occam’s Razor altogether. I had considered checking chamber dimensions, and perhaps even changing the chamber dimensions with a reamer if necessary, but to my surprise, mixing in the brass seemed to work. I still need to do more testing, though.
The more input and suggestions the better, though, especially for people who might be experiencing problems that aren’t exactly like the ones that happened to me.
That’s the cool thing about opening a gun thread on Free Republic. There are a bunch of knowledgeable people here. Every time I’ve shared information about something I’ve discovered, I end up picking up more new info that what I shared.
Thanks.
I should have mentioned this about measurement:
If I sit down with high quality ammo (never mind Russian or ChiCom cut-rate stuff) and measure them, I’m going to find variances. There is almost no manufacturing process that can maintain super-tight tolerances down to, oh, less than one-thousandths of an inch without huge inspection/maint/culling protocols and expenses. There are variances on the length of the case, the thickness of the neck, the concentricity of the bullet in the neck, the roundness of the case, the diameter of the case, etc.
In ammo, I’ve measured brand-new cases from US high-quality manufacturing plants of as much as .003” in areas like length, neck diameter, etc. I’ve seen variances in weight between cases as much as 3 grains. Again, this is the good stuff. The best stuff will be tighter yet, but the price starts heading for the moon. Instead of buying the very best, I’ll often buy bulk “good stuff” and then measure/sort brass, sell off what I don’t want, etc.
You’ll see some plants and companies have more and less variance. What’s more is that as tooling and machines wear, sometimes the mean of the measurement starts to drift upwards... so that some of the stuff that is on the outside statistical edges will fall outside the allowed bounds of the chamber.
So not every case or round where the tolerances are out of spec will fail to feed because not every round will be out of spec. If the reloading plant’s dies are getting worn, hey, maybe one-in-ten rounds is out of spec, maybe more if they’re a foreign outfit and they don’t have to listen to complaints.
Part of why there’s a designed-in slop between the chamber size and the SAAMI max ammo dimensions is to allow for dirt, ammo dimensional variance, etc. That’s also the reason for allowances in go/no-go headspace dimensions.