One-in-a-billion Bushmaster

[IM_JOHNNYV]

My neighbor asked me to take his Bushmaster AR15 to the range to see if I could find out why it would not eject. He inherited the rifle from his brother and when he received it, it was unfired and new in the box. He (neighbor) went to the range after getting the rifle and the first two shots ejected normally, but then it would no longer eject - sounded strange to me. I inquired about the ammo and if the rifle was properly lubricated and he said he thought it was. So before going to the range I did my normal preliminaries, checked to make sure it was empty, the rifle cycled properly when empty, action lubricated, and gas tube clear of any obstructions - all OK. I took to the range some Federal 55 and 62 grain bullets. First shot - FTE, second - FTE and all subsequent rounds FTE. Accuracy was phenomenal, shooting under ½" groups consistently - STRANGE, to say the least.

Took the rifle back home and started double and triple checking everything and found what I believe to be a One-in-a-billion oddity. When my neighbor fired the second shot out of the rifle, during the ejection cycle, the case had an apparently loose primer that unseated itself, was in mid-air when the bolt started its forward cycle, and found its way into the gas key, restricting gas from entering the bolt to start the ejection cycle. If you check the primer size, you'll see it fits the gas key perfectly and can completely restrict the gas flow.

After removing the primer, the rifle functioned flawlessly. Truly One-in-a-billion....

[imschur]

wow  <laughs>

[planeflyer21]

Great...last time I read something like that it happened to me the next time I went shooting.  In that case it was a loose primer dropping into the trigger group.

Jon

[unforgiven]

:o Good eye brother JOHNNY. <thumbsup>

[Madhouse]

Good find.  How is it you ended up even looking in the gas tube?

[IM_JOHNNYV]

Good find.  How is it you ended up even looking in the gas tube?

Process of elimination using compressed air. If the gas doesn't move, then neither does anything else. <thumbsup>

[planeflyer21]

That would be a suck-o-la in a firefight.

Jon

[IM_JOHNNYV]

Could be one reason you see a lot of military ammo with sealant around the primer....

Makes me wonder......

[planeflyer21]

Don't know if it is correct or not, but had read that the primary reason European and commie countries sealed the primers was to keep moisture out.

That wonderful military crimped-in primer is so they don't come out.

Jon

[SPBCTS]

Just when you think you've seen everything something like this comes along.

Great find, really.

A great story for BS sessions...