What are the characteristics of an over pressure round?

[Arik]

I know pictures are worth a 1000 words but I didn't take one and this has been bothering me for 2 days.

On Saturday I took an AK class and everything was going great until the end. At the time I was using a Bulgarian 74 5.45x39 with wolf ammo.

On the last drill everything was going fine till I got to maybe 3rd of 4th round when I had a malfunction. I was in prone with the mag resting on the ground. The bolt in the open position. I go to run the bolt thinking the previous case may have gotten caught. Nothing....bolt stuck to rear. I the go to remove the mag, a E. German bakelite, and it won't budge. The mag release is locked up. One of the mags on me was a Polish steel mag. I use it to smack the mag release and after a few good smacks it works and dislodged the release.

One round falls out, the one that it had tried to chamber after the previous one was fired and the bolt closes but not all the way, and needs to be mortared to be opened up again. I notice the fired case is stuck in the chamber with about a quarter of it sticking out. The rim, where the extractor holds it, is torn off. I let the gun cool then inserted the cleaning rod and tried to tap out the casing using the steel mag. Didn't work. Since I had to be somewhere after this and still had an hour drive I didn't mess with the rifle, just threw it in the car and left. Yesterday I was too busy and later to pissed off to mess with it.

The ammo was wolf with the grey steel casing and I can't remember if it was from the black flat box or the military classic square camo colored box.

From what I can see the primer seems to have bulged out a little.
I've never had issues with ammo in any caliber or style. I'm guessing that that round was overpressured?!?!!?

What damage if any should I look for?

[georgeib]

I know pictures are worth a 1000 words but I didn't take one and this has been bothering me for 2 days.

On Saturday I took an AK class and everything was going great until the end. At the time I was using a Bulgarian 74 5.45x39 with wolf ammo.

On the last drill everything was going fine till I got to maybe 3rd of 4th round when I had a malfunction. I was in prone with the mag resting on the ground. The bolt in the open position. I go to run the bolt thinking the previous case may have gotten caught. Nothing....bolt stuck to rear. I the go to remove the mag, a E. German bakelite, and it won't budge. The mag release is locked up. One of the mags on me was a Polish steel mag. I use it to smack the mag release and after a few good smacks it works and dislodged the release.

One round falls out, the one that it had tried to chamber after the previous one was fired and the bolt closes but not all the way, and needs to be mortared to be opened up again. I notice the fired case is stuck in the chamber with about a quarter of it sticking out. The rim, where the extractor holds it, is torn off. I let the gun cool then inserted the cleaning rod and tried to tap out the casing using the steel mag. Didn't work. Since I had to be somewhere after this and still had an hour drive I didn't mess with the rifle, just threw it in the car and left. Yesterday I was too busy and later to pissed off to mess with it.

The ammo was wolf with the grey steel casing and I can't remember if it was from the black flat box or the military classic square camo colored box.

From what I can see the primer seems to have bulged out a little.
I've never had issues with ammo in any caliber or style. I'm guessing that that round was overpressured?!?!!?

What damage if any should I look for?

Almost sounds like you may have a bullet lodged in the bore...

[Arik]

Almost sounds like you may have a bullet lodged in the bore...

Couldn't tell but the cleaning rod goes all the way down. Just the tip sticking out

[Arik]

This is making less and less sense now.

I went to try to knock out the casing. No luck. So I decided to check out the mag. At first I inserted a different mag and it locked in and came out fine. The I inserted the mag that was in the gun when this happened. It locked in fine but was a little more difficult to unlock. Then I looked at another mag, a Polish steel one and it had a large dent in it. Totally F'd. Follower is stuck, rounds just fell out after I took the first one out. 2 rounds also had dents.

So im thinking out of battery fire and the bakelite mag didn't fly out due to resting on the ground. But none of the ammo got damaged either.

Then I'm thinking maybe the pressure hit the metal mag causing it to have a huge dent but there's no damage or burn marks on the check rig where that mag was.

Then I thought maybe the dent is unrelated and I simply fell on something when I went prone and didn't realize it in all the excitement. But I'm a lefty and that part of the mag was facing my body not the ground!


WTF!

[georgeib]

Start by squirting some Liquid Wrench around the casing and in down the barrel, and then give it an hour or two to soak. Then try removing the stuck casing again.

[Lefty223]

Start by squirting some Liquid Wrench around the casing and in down the barrel, and then give it an hour or two to soak. Then try removing the stuck casing again.

FWIW a DIY 50/50 mix of acetone and auto transmission fluid (ATF) was proven by Practical Machinist to be the BEST solvent for remove stuck or frozen items by a huge factor! 2X better than Kroil, which was the best of the commercially available solvents. LW was way down the list ...

[RetroRevolver77]

delete

[Arik]

Remove your muzzle brake. Run your cleaning rod down the bore until you make contact with the casing, then tap the rod with a hammer.

Why didn't I think of that! I tapped the rod with a mag, the a hammer. When that didn't work I flipped it upside down and hit the rod against a concrete floor. Still stuck, but now at a gunsmith

[RetroRevolver77]

delete

[Arik]

You used a mag without any density which is not a hammer. You use either a hammer when at home or if on the range- run the rod into a fixed surface like a tree or a bench, something that isn't going to move. It takes a lot of force when that happens. Worse case scenario is you have a ripped shell casing shoulder stuck in the chamber and another casing shoved in behind it. I actually hope that is scenario since you decided to be a smartass in your reply. LOL.

The case is empty. When you put the rod in you can hear it hit the inside of the case. If it was another ripped casing this one wouldn't have fired. It sticks out far enough that the bolt doesn't close ..... doesn't come close to closing.

At home I let it soak and flipped it upside down and hit the rod against the floor. Doesn't budge. Yesterday I gave it to a gunsmith