Tula is dirty, but light primer strikes after 200 rds?

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Pistoler0

New member
My 7.62x39 AR (by Atheris rifle) is great and I am happy with it, but the only issue is that I start having light primer strikes after roughly 200 rds.

I installed an "enhanced" firing pin in it so that it could deal with harder russian ammo primers. I purchased (but have not installed yet) a stronger firing spring. I didn't put it in yet because it is my understanding it makes the trigger pull a bit heavier.

Is it normal for the bolt to get so dirty to have light primer strikes after only 200 rds?

What I do is take the bolt carrier out, spray the whole thing thoroughly with CLP or Ballistol, and it is back to shooting again.

What is one to do if in the middle of a class or competition? 200 rds would go very fast, I assume.
 
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stagpanther

New member
but the only issue is that I start having light primer strikes after roughly 200 rds.
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In other words, you get "normal" full power strikes at first but it slowly degrades to where after 200 firings the pin strikes get lighter on the primers?
 
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Carl the Floor Walker

Moderator
After receiving a Beretta Nano, I went on a quest to see how many rounds I could fire through it, but the ammo shortage stopped me from continuing. I made it close to 15,000 in a fairly short time. During that time I shot just about everything. The only thing that would stop it was Tula and Wolf when the gun became dirty. And I shot a whole lot of this ammo. BUT, as soon as that happened, I would just take a cotton swab and quickly clean the feed ramp and then would keep on trucking.The Powder itself is a dirty powder, but not a sticky type. It was always easy to clean once I got home. Other than that I had no issues. This is also the case with shooting other guns I own with that ammo.
 
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Pistoler0

New member
stagpanther said:
In other words, you get "normal" full power strikes at first but it slowly degrades to where after 200 firings the pin strikes get lighter on the primers?
Click to expand...
Yes stagpanther, that's exactly what happens you described it perfectly

DoubleNaught, I installed the "enhanced" firing pin from the get go, because initially the rifle was sent to me without a BCG and I sourced one on my own.
 
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Shadow9mm

New member
Pistoler0 said:
Yes stagpanther, that's exactly what happens you described it perfectly

DoubleNaught, I installed the "enhanced" firing pin from the get go, because initially the rifle was sent to me without a BCG and I sourced one on my own.
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what makes the "enhanced" firing pin enhanced? is it a different material like titanium? is it lighter or heavier? does it protrude more? is it possible its over sized in the bolt and dragging? Have you removed and cleaned your firing pin. Are you lubing it, I always keep mine dry so fouling does not stick.

Tula is weak, dirty, and steel cased. steel does not expand and seal nearly as well as brass. and with weak ammo there will be an even weaker seal meaning a lot more fouling getting around the casing back to the bolt.

With that said, you should get more than 200rnds before its too fouled to run....
 
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Hawg

New member
Carl the Floor Walker said:
After receiving a Beretta Nano, I went on a quest to see how many rounds I could fire through it, but the ammo shortage stopped me from continuing. I made it close to 15,000 in a fairly short time. During that time I shot just about everything. The only thing that would stop it was Tula and Wolf when the gun became dirty. And I shot a whole lot of this ammo. BUT, as soon as that happened, I would just take a cotton swab and quickly clean the feed ramp and then would keep on trucking.The Powder itself is a dirty powder, but not a sticky type. It was always easy to clean once I got home. Other than that I had no issues. This is also the case with shooting other guns I own with that ammo.
Click to expand...
It's not so much that the powder is dirty. Steel cases don't expand as much as brass does so you get more blow-by than you do with brass.
 
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stagpanther

New member
Yes stagpanther, that's exactly what happens you described it perfectly
Click to expand...
Sounds like residue build-up might be contributing to the problem if it's a gradual deterioration thing. Is there a special trigger group installed for reduced trigger pull? Might be something reducing the effectiveness of the hammer strike on the pin. I'd try a better quality ammo and see if the same problem repeats. What does the rifle manufacturer say about the issue?

Are you sure the BCG headspace correctly? Many people just assume correct headspacing is "automatic" with AR's--which is often true, except when it isn't.
 
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Joe-ker

New member
Shadow9mm said:
what makes the "enhanced" firing pin enhanced? is it a different material like titanium? is it lighter or heavier? does it protrude more? is it possible its over sized in the bolt and dragging? Have you removed and cleaned your firing pin. Are you lubing it, I always keep mine dry so fouling does not stick.

Tula is weak, dirty, and steel cased. steel does not expand and seal nearly as well as brass. and with weak ammo there will be an even weaker seal meaning a lot more fouling getting around the casing back to the bolt.

With that said, you should get more than 200rnds before its too fouled to run....
Click to expand...
The shoulder is machined a little more so the pin protrudes a bit further on firing. It is same overall length. It is a must on 7.62 builds.

I recently build one…..I had a couple light strikes on some old military surplus stuff. But has been flawless since. All wolf ammo here now.
 
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Onward Allusion

New member
You did not mention WHICH Russian ammo. I have personally experienced this with the steel cased poly ammo - Wolf and Brown Bear. It's not a problem with the primer. The problem is caused by the poly residue melting due to the gun getting hotter with usage. That and the steel case -vs- brass thing.

You pause and clean and that gets rid of the gunk and lets the gun cool. The melted poly residue is not letting the gun chamber and function at 100%, hence your "light strikes".

Why is this happening to your AR chambered in a Russian round? Because these types of Russian rounds are made for AK patterned platforms - loose tolerances.

Yes, old, slightly fat, but with some knowledge. :)
 
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Joe-ker

New member
Onward Allusion said:
You did not mention WHICH Russian ammo. I have personally experienced this with the steel cased poly ammo - Wolf and Brown Bear. It's not a problem with the primer. The problem is caused by the poly residue melting due to the gun getting hotter with usage. That and the steel case -vs- brass thing.

You pause and clean and that gets rid of the gunk and lets the gun cool. The melted poly residue is not letting the gun chamber and function at 100%, hence your "light strikes".

Why is this happening to your AR chambered in a Russian round? Because these types of Russian rounds are made for AK patterned platforms - loose tolerances.

Yes, old, slightly fat, but with some knowledge. :)
Click to expand...
The poly was created for the AR platform to aid in feeding since the old laquer style can lead to more gunk. Not going to say you are wrong at all but I’d like to think the poly will be more reliable.
 
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jetinteriorguy

New member
If any of my AR’s is acting up I just douse it with oil and it works again, except my Zero Fail BCG which has never failed no matter how dry or dirty.
 
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Pistoler0

New member
stagpanther said:
Sounds like residue build-up might be contributing to the problem if it's a gradual deterioration thing. Is there a special trigger group installed for reduced trigger pull? Might be something reducing the effectiveness of the hammer strike on the pin. I'd try a better quality ammo and see if the same problem repeats. What does the rifle manufacturer say about the issue?

Are you sure the BCG headspace correctly? Many people just assume correct headspacing is "automatic" with AR's--which is often true, except when it isn't.
Click to expand...
Stag, I didn't install a new trigger, I think that it might be blow back build up.

I am going to put in a stronger firing spring and see if it solves the issue.
 
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rickyrick

New member
If it was mine,
200 rds and starts having issues, like light primer strikes, I’d be concerned and hesitant to fire it until I was relatively certain as to the cause.
But, I have no experience with 7.62x39 rifles.
Many stories and video accounts of blown up ARs involves an AR getting finicky not long before the boom.
I’ve had a few light primer strikes in some rifles, (not ARs) involved viscous lubricant getting into the firing pin channel.

In ARs, I haven’t had any light primer strikes, but I have heard of it with Russian ammo.

Probably not a dangerous condition, but I’m an over cautious big chicken.
You have a symptom of something going on, I’d try a regular firing pin if there’s no oil or gunk in the channel.
 
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