AR Bolt Failure!

[brwnfldl]

Soooo, havent seen this before. Anyone else? One chunk went into the chamber, the other went down into the lower. Thankfully the round failed to seat. I almost thought of using the foward assist for the first time, sooooo glad I stopped to check it out.

 

[shooter521]

Yes, I've seen it before. How many rounds on that particular bolt, and who's the manufacturer?

 

[brwnfldl]

Bushmaster, close to 6k rounds. This a common thing? Metal fatigue, cracks?
How often should I be replacing the bolt?

 

[djl02]

I alway thought after 5k it needed replaced or upgraded. (barrel and bolt)

 

[shooter521]

Bushmaster, close to 6k rounds. This a common thing? Metal fatigue, cracks? How often should I be replacing the bolt?

Not an especially common failure (particularly in commercial guns), but not unheard of, either. Given the round count, I would say it's just honest wear rather than some kind of manufacturing flaw, though I might expect it closer to 10K assuming a "normal" firing schedule. Replace the bolt and drive on.

If it was a "bad" bolt, I would have expected it to crack at the cam pin hole rather than shearing a lug, and at a much lower round count.

I alway thought after 5k it needed replaced or upgraded. (barrel and bolt)

I do not regard the bolt as a planned replacement part; I'll shoot it until something breaks. That said, I have seen 10K thrown around as a benchmark by knowledgeable folks whose opinions I trust. A good chrome-lined carbine barrel should last at least twice that many rounds, again assuming a normal firing schedule and normal ammo.

My

 

[Dtruck260]

WOW, hope I never see that on mine!

+1 for BFBC2 in the background, lol

 

[DaKruiser]

The round failed to seat, did you pull the trigger, and then notice? That looks scary to me not sure what all else would have came apart if the round had went off. Good for you and anyone around you it didn't! I hope I never see this, well I would like to have the time to shoot that much!

 

[CombatVet]

I've seen it a time or two when I was an armorer in the military. Not very common though.

 

[zsm]

It is common, for the fact that if a bolt breaks, it will usually break at the two lugs adjacent to the extractor or the cam pin.

This happens because the ar15 bolt

Get a new bolt from denny/bcm/spikes, or if you want something even more durable, get an enhanced bolt from jp or something