Anyone experiencing blown AR extractors with metal cases

jdman, i'll give you one guess...
and yes it was replaced under warranty. and no, I haven't tried it. I just moved to vic, so still unpacking - then off to work again. easily about 600 rounds before it started to ftf/fte, and I took a look and was like wtf.
 
ok it was NEA, geeeeeze

I just got a DPMS 7.62x39 bolt, I think I remember someone mentioning that norinco steel cased ammo destroyed his extractor too, kind of worried as its the only non-corrosive ammo I have and those bolts are impossible to find
 
Out of curiosity, what length barrel ? What gas system length ? Do you know your buffer weight ? and what direction is your brass chucking ?
 
They do, gives more time for the pressure to recede for easier extraction.

IF your timing is off, it's trying to pull the case out while the pressure is still high and the case sealed in the chamber.
When this happens with brass, the extractor will actually jump off the rim, usually taking a gouge out of it, then it will pick up the next round and shove it right into the back of the one still stuck.

I've had this problem before under experimental circumstances. I reload and have an adjustable buffer, so I've been able to tinker with many different weights, and seeing how they react to powders of different burn speed.

I've done a lot of weight/timing experiments, and I always seems to end up with my buffer at it's heaviest weight. 6oz. My AR runs with Swiss movement and never have extraction issues with known good configurations. I chuck to 4'oC, and 3500 rounds in, my extractor is still running strong, and I got the bolt used.

I have not shot a lot of steel, but I imaging the steel rim would not give way as easy as brass would, so it could be very hard on the extractor.
I would inspect your spend cases for signs of gouging on the rim.

Never had any problems running steel with my config, but I don't have a 7.5", and have never shot more then 100 rounds of it in one session before cleaning.

Not saying this is your problem, 3'oC is reasonable. It is something to consider tho'. First thing I'd try anyway.

There is also the factor, mentioned already, of enamel build up in your chamber. I assume you scrub out your chamber as part of your regular maintenance schedule.

The metal of the steel case is softer then the metal your bolt/extractor is made of, so it can't harm it, in theory.
It's generally regarded as perfectly safe for an AR, provided you have compensated and can manage the enamel build up.
They recommend bringing chamber cleaning tools to the range for extended shooting sessions.

If it was me, I'd make sure to keep my chamber clean, and advance my buffer timing, and see if that helps.
 
I run an o ring on my extractor spring. Funny the extractor is fine, and still quite "edgy" but the lugs are gone. Different metals? Different pressures?
 
Conte said:
They do, gives more time for the pressure to recede for easier extraction.

IF your timing is off, it's trying to pull the case out while the pressure is still high and the case sealed in the chamber.
When this happens with brass, the extractor will actually jump off the rim, usually taking a gouge out of it, then it will pick up the next round and shove it right into the back of the one still stuck.

I've had this problem before under experimental circumstances. I reload and have an adjustable buffer, so I've been able to tinker with many different weights, and seeing how they react to powders of different burn speed.

I've done a lot of weight/timing experiments, and I always seems to end up with my buffer at it's heaviest weight. 6oz. My AR runs with Swiss movement and never have extraction issues with known good configurations. I chuck to 4'oC, and 3500 rounds in, my extractor is still running strong, and I got the bolt used.

I have not shot a lot of steel, but I imaging the steel rim would not give way as easy as brass would, so it could be very hard on the extractor.
I would inspect your spend cases for signs of gouging on the rim.

Never had any problems running steel with my config, but I don't have a 7.5", and have never shot more then 100 rounds of it in one session before cleaning.

Not saying this is your problem, 3'oC is reasonable. It is something to consider tho'. First thing I'd try anyway.

There is also the factor, mentioned already, of enamel build up in your chamber. I assume you scrub out your chamber as part of your regular maintenance schedule.

The metal of the steel case is softer then the metal your bolt/extractor is made of, so it can't harm it, in theory.
It's generally regarded as perfectly safe for an AR, provided you have compensated and can manage the enamel build up.
They recommend bringing chamber cleaning tools to the range for extended shooting sessions.

If it was me, I'd make sure to keep my chamber clean, and advance my buffer timing, and see if that helps.
Click to expand...

Thanks ill look into that. Just ordered a new extractor so ill see how it works. The brass looks fine so ill clean her all up and run a few rounds and see how it's working out.
 
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