03-16-2020, 03:23 PM
I bought a 12 Group Buy 1:1.75 twist barrel and bolt but all I had time to do was check the C.O.A.L. and the specs on the bolt. I have used the same bullets to measure eight 6.5 Grendel AR-15 barrels. My 12 Green Mountain barrel gives almost the exact same seating depth with every bullet as my 20 Shilen barrel. The length and bolt face depth on my new Monster bolt is spot on. My other Monster bolts have also been spot on and by appearance are excellent quality.