I sure could use some help here.
I don't know much about overpressure situations. My new-to-me M44 Mosin-Nagant was exhibiting a "sticky bolt" while shooting some Russian surplus ammunition from 1986.
It has no problem shooting heavy ball from Hungary made in 1951. The action is very slick using that stuff and I can reach over and operate the bolt handle with no problem (I'm a lefty). The ammunition is copper washed steel.
The Russian stuff is light ball. It has a laquered case mouth and primer, and the case is not laquered. It is copper washed steel as well.
When I first fired it I could hardly get the bolt open. I then came to the internet forums and found that the Mosin-Nagants have "sticky bolt syndrome." I followed the steps to correct this.
While it helped somewhat, the problem still existed.
I took a closer look at my spent cases. This is typical of what I found on the Russian stuff.
At first I thought these were a couple scratches, perhaps manufacturing defects.
I then noticed that the case is cracked, with light visible through the crack.
The rifle is OK. It's sturdy, if not purdy :)
Can someone tell me if this is a sure sign of overpressure? I don't know what else to look for; I've never seen an example of a flattened primer.
The bands which go around the cases look to be from some sort of annealing process. Looks like other heat treated metal I've seen.
Also, this ammo blows moisture of some sort back. Is this indicative of anything?
Overall, what exactly am I looking at gents? Over pressure, or is this typical of Russian stuff?
Personally, I think hard extraction + random case ruptures = overpressure.
The case code is "60" at 12:00 and "86" at 6:00 for those who may be wondering. I do not have a lot number.
Any help is appreciated.