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Can anyone tell me if Azimuth bolts use a standard length firing pin. I remember some manufacturers (Toolcraft?) using shorter than standard pins and I'd like to avoid that if possible. While we're at it, has anyone used one of their bolts? Diamondback has their BCG on sale for 75 bucks shipped right now and I'm considering grabbing one if it's a decent piece.
- Kirk -
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I have no experience with Azimuth products. The specification I found for AR-15 firing pins is 3.2790 with a tolerance of minus -.007. I had one Colt firing pin measure 3.2800. For a short period of time Toolcraft used 2.800 length 6.5 Grendel bolt with .136 bolt face depth. This shorter bolt requires a shorter 3.269 firing pin. Alexander Arms lengthened their 6.5 Grendel bolts to 2.810 so standard mil spec firing pins could be used. The longer length is because of the .01 deeper bolt face depth compared to 5.56/223 bolts (.125 bolt face depth and 2.800 bolt length).
There can be around .002 in tolerance in bolt measurements and there is a tolerance of .008 in firing pin protrusion to accommodate manufacturing tolerances. Firing protrusion spec for AR-15 is .028 to .036 regardless whether 5.56/223 or 6.5 Grendel.
Posts: 221
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Joined: Jun 2017
VASCAR2 Wrote:For a short period of time Toolcraft used 2.800 length 6.5 Grendel bolt with .136 bolt face depth. This shorter bolt requires a shorter 3.269 firing pin
Yes, I remember reading that here. I couldn't remember if any other manufacturers had done that and my searches didn't turn anything up. I understand that Azimuth makes good 5.56 stuff but I never heard anything about their 6.5G bolts. Thanks for the refresher on the bolts.
- Kirk -