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Bama27139
16 April 2017, 19:56
I just finished a LR-308 building with a polymer lower and DPMS upper and a area precision BCM. I shot it today for the 1st time and ran into a problem. Any help you can give me is great. I can manually put a round in the chamber and it fires fine and it will cycle good and put another round in the chamber but the next round will not fire because of light primer strike. I can manual cycle and it will fire fine but the same thing happens. Thanks in advance for the help.

UWone77
16 April 2017, 20:18
I'd start with... did you install the hammer spring correctly in the right orientation?

Eric
17 April 2017, 05:34
http://img.photobucket.com/albums/v503/AR15forme/FCG.jpg (http://smg.photobucket.com/user/AR15forme/media/FCG.jpg.html)

SINNER
17 April 2017, 05:53
I am assuming you mean a Aero Precision BCG? If so you have the most jacked up BCG I've seen. I purchased 4 of them and they all had the same issue. The diameter of the firing pin is too large for the pilot hole through the bolt. The protrusion was half of the protrusion of multiple other carriers I checked. The pins would actually get stuck in the carrier with the slightest amount of carbon. Very scary to think of the potential of accidental discharges if the pin got stuck out far enough to cause a fire before the bolt locked into battery.

I wound up taking a few thousandths off the pins in my lathe. 2 of the BCG's I actually had to remove the gas key to get the cam pin out. I have BCG's from other .308's that require some force to remove the cam pin but even with 2 screwdrivers under the pin these would not pass by the gas key. You could see the keys on the carriers that had issues were not rounded off to allow the cam pin to pass by.

Bama27139
17 April 2017, 07:16
thanks I have checked the hammer spring I have done that once before

Bama27139
17 April 2017, 07:20
thank you for the info I took the BCG apart and the firing pin was tight but I lubed it good and it was better will take apart again I do not have a lathe but I will see if I can work on it

SINNER
17 April 2017, 08:06
I actually have a pic showing how far the firing pin was stopping from the tail of the bolt. The taper at the front of the pin that actually passes through the bolt face is where the binding was occurring. I cut that taper back very slightly and the firing pin then bottomed on the tail as designed.

FYI I have yet to find any other firing pin that will work in an Aero BCG. I must have pulled the pins out of 10-12 BCG's and not one is close in dimensions to their pins.

3145

Joelski
6 June 2017, 17:11
http://img.photobucket.com/albums/v503/AR15forme/FCG.jpg (http://smg.photobucket.com/user/AR15forme/media/FCG.jpg.html)
This is perfect for showing people why their anti-walk pins are basically a decoration.

mustangfreek
7 June 2017, 18:19
I am assuming you mean a Aero Precision BCG? If so you have the most jacked up BCG I've seen. I purchased 4 of them and they all had the same issue. The diameter of the firing pin is too large for the pilot hole through the bolt. The protrusion was half of the protrusion of multiple other carriers I checked. The pins would actually get stuck in the carrier with the slightest amount of carbon. Very scary to think of the potential of accidental discharges if the pin got stuck out far enough to cause a fire before the bolt locked into battery.

I wound up taking a few thousandths off the pins in my lathe. 2 of the BCG's I actually had to remove the gas key to get the cam pin out. I have BCG's from other .308's that require some force to remove the cam pin but even with 2 screwdrivers under the pin these would not pass by the gas key. You could see the keys on the carriers that had issues were not rounded off to allow the cam pin to pass by.


Wow...missed this before..

Sounds like a real cluster phuck . Are you still using them , or like the guy on ar15 that cut his aero lower in half cause something was out of spec...[BD]

Eric
8 June 2017, 02:48
This is perfect for showing people why their anti-walk pins are basically a decoration.
If you need anti-walk pins something is wrong.

Former11B
8 June 2017, 03:26
Wow...missed this before..

Sounds like a real cluster phuck . Are you still using them , or like the guy on ar15 that cut his aero lower in half cause something was out of spec...[BD]

That was a Spikes lower, IIRC

mustangfreek
8 June 2017, 04:14
That was a Spikes lower, IIRC

I remember that one, but no kinda recent dude over there got pissed the safety selector didn't fit right, IIRC...chopped a aero lower right in half...lol