AR Sponsor
Posted: 11/15/2012 4:52:30 PM EDT
|
My step dad recently put together a mid-length upper and it is failing to extract on every round. I have tried Silver Bear, surplus, Hornady, and a couple other manufacturers and every time it fails to eject and the bolt carried is only out of battery just enough so that I can see a little bit of brass. I took it apart earlier today and I am thinking that the gas port is too small, it measured .054. It has a regular mil-spec buffer, and spring and a Palmetto state BCG, but I had swapped that out with my LMT one and it did the same thing. It also acts the same on all of my lowers.
So basically would I have to have the gas port enlarged or is there something else I should try first? |
|
What is the barrel length, 16"? .750" gas block journal?
Have you already examined the gas system for leaks or misalignment? A couple of common failure points are sliding a low profile gas block all the way to the shoulder on the barrel leading to a partially obstructed gas port, and a loose or leaking gas key to bolt carrier junction. |
| Well there is an almost perfect outline from the hole in the gas block around the gas port, is opening that up something that can be done with a mill or a drill press or is it better to send it off? I measured the gas port on my mid-length earlier and mine is at .0695 so I am guessing his is pretty under spec. |
AR Sponsor