I have had off/on problmes with an Essential Arms lower.  

I seem to have all the problems fixed except for one. (I replaced the 'lower guts', recoil spring, disconnector, sear etc)

The gun seems to be 100% reliable except when I am bump firing.  

It will rattle off 3-15, rounds in a long (fast!) burst, then jam.  The jam is almost always a round in the chamber, but without a 'cocked' hammer.  (occasionally a round will 'jump' the bolt.)

To continue firing you have to fully open the bolt, eject the round, chamber a fresh round, and fire another burst.

I have tried different magazines, all seem to give equal number of randomly spaced jams. (failure to fire?)

I get the same basic problem with my DR200.  

Do all guns work like this when being bump fired?  I am assuming it is because the gun is 'floating' in the air without the benefit of a shoulder to recoil against.

TheRedGoat


BTW, East Texans, Dallas Dwellers, check the meetings and events message area to give us some ideas on where/when to have a shoot....

Stop Bump Firing!!!   Problem solved.
You can't expect ANYTHING in the way of reliability when you are doing the bump...

The probelm you are having happends in ALL guns when BF.  The hammer is falling too early and the bolt isn't locked up yet. You may notice a dimpled primer.


BISHOP

Obviously you have a rifle with the T/C anti-bump tigger module installed.  American makers have been using these for a while now.

LOL!

1. Buy an AK-47
2. Bump fire and abuse it all you like.
3. Save the AR for REAL shootin'

i got introduced to Mr. Bump via a Norinco preban 223 AK and it would do the very same  thing..

Speaking of the Bump i was at the range this weekend and a kid had a brand new Armalite AR with midlegnth forearms and compensator (Cool gun)...He said something about wishing he had a full auto and i told him he did and i bumped about 10-15 rounds.  He went nuts and wanted to try it but those were his last rounds i shot....he left to get more ammo....Dick

What is bump firing?

slowhand, Bump firing is using the recoil of the gun to 'simulate' cyclic firing.

Dickwholliday, same reaction when I showed the neighbors up the road the trick...  

You are firing faster than the gun could cycle. Slow down your rate of bump.

Sounds like the action isn't getting far enough back to cock the hammer.  The action depends on the inertia of the gun to work against.  When bump firing there is less inertia because you're letting the gun move back with the action.

You could always try hotter ammo.

Thanks for the advice guys/gals.

You have confirmed my theory.

A novelty way to fire, but not foolproof.

TheRedGoat