Abnormal wear? (Bolt carrier-rear trunion contact)

[geofri 4]

Some pening on the back of the botl carrier, and the gnashing of the bolt carrier to the rear trunion made it a little stick to remove the recoil spring.. will this slow/stop after some breaking in?

 

 

 

[kdbutler 563]

Ouch. I'm afraid I don't know much about that, but I'd look into replacing the recoil spring perhaps. I'm sure you'll get better responses from members with more experience on the issue.

[joek4061 6]

They all have this to some degree or another. I wouldn't get overly worked up about it. If you want you can try a buffer and or a wolf 10% recoil spring.

[scattergun10 125]

They all have this to some degree or another. I wouldn't get overly worked up about it. If you want you can try a buffer and or a wolf 10% recoil spring.

 

What he said.

[jimdigriz 580]

Do you have a hammer spring other than the factory one?

[postbanben 9]

what rifle is this?that is significant striking from what i've seen.i have a sgl 21 that does this and it made the recoil spring stick when taking it out.my saiga conversion with an a2 does it less.it drives me nuts.

[imarangemaster 315]

That is not abnormal for an AK. I am not generally a fan of recoil buffers on AKs, but if it is cycling fine, I would just get one rather than screwing with springs.

[my762buzz 141]

A factory installed adjustable gas block sort of like the Saiga 12 or more like a multi level similar to a FAL might help with tuning the gas system to the specific load. Can anyone be 100% certain that their favorite loads are not overgassing the cycle and beating the hell out of their gun. The argument can be made that if it needed a gas regulator the original AK47, AKM, AK74M, or etc would have been designed that way. The problem is that a specific mil spec issue load is also designed around the original systems and a commercial NON mil spec load may increase the gas pressure at the gas block to an already generously overgassed system making things far worse.

[postbanben 9]

good point.what commerc load is most like the military round?

 

i wouldn't doubt the conversation for a gas regulator went like this "should we put a gas regulator?" "no we have to keep it simple i have no faith in a common soldiers ability to use one,over gas the bitch and who cares if americans grand kids have the rivets fall out."

[my762buzz 141]

good point.what commerc load is most like the military round?

 

There are several factors to consider here. Checking powder types and powder weights would take a long time.

Since saigas are basically modified ak74 mechanisms, the ak74 mil spec rounds would serve as an ideal mil spec model.

Suppose someone observes how far a 5.45x39 saiga ejects 7n6 from the rifle. A 7.62x39 saiga should have nearly the same cycle

speed and ejection distance. This sets a standard control. If 7n6 ejects 15 ft away on average, then any commercial 7.62x39 load should not eject any farther away. It would be good to note that even though many would consider muzzle exit velocity this does not indicate the exact gas pressure at the gas port for that load. Different loads can have different varying pressure points depending on rate of burn, yet could still have similar exit velocities. However, the bolt carrier velocity is based on the exact gas pressure at the gas block, and so is the ejection distance.

Edited December 28, 2011 by my762buzz

[IndyArms 10,189]

It will be just fine... Yall are overthinking this whole thing way too much.

It's made to be fixed by being beat on with hammers... It can be run over by a truck, dumped in the sand, and picked up and fired without more than a cycling of the action... It will be fine. If your shells eject 15 feet or 18 feet its EJECTING them... its WORKING. If you get a 16th of an inch of shiny steel at the rear trunnion... smile, and load another mag and shoot some more. It's all good.

 

 

 

[imarangemaster 315]

It will be just fine... Yall are overthinking this whole thing way too much.

It's made to be fixed by being beat on with hammers... It can be run over by a truck, dumped in the sand, and picked up and fired without more than a cycling of the action... It will be fine. If your shells eject 15 feet or 18 feet its EJECTING them... its WORKING. If you get a 16th of an inch of shiny steel at the rear trunnion... smile, and load another mag and shoot some more. It's all good.

 

 

 

I agree. A buffer would be just fore your peace of mind. My AKs have all had some variation of that wear, and never have had any kind of failure. My current Saiga is an anomaly, in that it had none of that wear, but I have a vented Chinese Type 56 gas tube on my restoration. The lack of it is more unusual than having the peening.

[postbanben 9]

good point.what commerc load is most like the military round?

 

There are several factors to consider here. Checking powder types and powder weights would take a long time.

Since saigas are basically modified ak74 mechanisms, the ak74 mil spec rounds would serve as an ideal mil spec model.

Suppose someone observes how far a 5.45x39 saiga ejects 7n6 from the rifle. A 7.62x39 saiga should have nearly the same cycle

speed and ejection distance. This sets a standard control. If 7n6 ejects 15 ft away on average, then any commercial 7.62x39 load should not eject any farther away. It would be good to note that even though many would consider muzzle exit velocity this does not indicate the exact gas pressure at the gas port for that load. Different loads can have different varying pressure points depending on rate of burn, yet could still have similar exit velocities. However, the bolt carrier velocity is based on the exact gas pressure at the gas block, and so is the ejection distance.

 

i don't have a 74 to do this experiment.if someone was to do this would it be best to have the guns equally braked or does it not matter?

[Scott Kenny 144]

It doesn't matter, because what you're (indirectly) measuring is gas pressure at the port. The brake uses gas that doesn't go into your gas system.

 

Reminds me, I need to do some playing around with new springs for Petra, even a Wolff extra-power spring isn't stiff enough.

[pjj342 632]

When my 02 saiga was in its factory config, it pounded the crap out of my trunion.

 

The only thing that worked, which wasnt for that purpose, was the texas ak FCG I used for my conversion. The hammer is higher and provides more push on the carrier as its moving rear ward. It was so high that when I took a file to it, while checking and checking, it took 2 hours to get it down to where the carrier would go over decently, but still not nearly as easy as over the factory hammer.

 

If your hammer has a factory like profile, a higher hammer might help, it completely fixed mine.

[imarangemaster 315]

When my 02 saiga was in its factory config, it pounded the crap out of my trunion.

 

The only thing that worked, which wasnt for that purpose, was the texas ak FCG I used for my conversion. The hammer is higher and provides more push on the carrier as its moving rear ward. It was so high that when I took a file to it, while checking and checking, it took 2 hours to get it down to where the carrier would go over decently, but still not nearly as easy as over the factory hammer.

 

If your hammer has a factory like profile, a higher hammer might help, it completely fixed mine.

 

Maybe that's why I have no pounding on my Saigha trunnion. I used a Texas AK double hook FCG on it. Nice observation.

[Rhodes1968 1,638]

It will be just fine... Yall are overthinking this whole thing way too much.

It's made to be fixed by being beat on with hammers... It can be run over by a truck, dumped in the sand, and picked up and fired without more than a cycling of the action... It will be fine. If your shells eject 15 feet or 18 feet its EJECTING them... its WORKING. If you get a 16th of an inch of shiny steel at the rear trunnion... smile, and load another mag and shoot some more. It's all good.

 

 

Man has a point.

If you cant stand it put a buffer in, just get a good one dont be cheap and keep a spare.

[Bigtwin 219]

I have/had a similar amount of wear. I was a bit concerned and asked aroud this forum. the answers were all over the place from changing the gas port to changing springs, and using a recoil buffer.

 

I started with a new recoil spring...same results. I used a marker to tell if it was still hitting the trunion, it was.

As I have read negitive things about the recoil buffer, I was reluctant to try it. Now I have one on my Saiga without any issues. No short stroking or any other issues.

 

Try one and see if it works for your rifle!