Started building my first AR15

[ViperHummel]

There is more to the 300blk vs the 7.62x39 than just grain offerings and magazine usage. The extraction on the x39 is much more violent due to the tapered case and the non tapered chamber. The pressure that is exerted on the thin bolt lugs results in higher failure rate (broken lugs).

[Square Bag]

Yep use a feeler gauge for spark plugs. Works like a charm.

[DavidH]

Thanks Bigandy,. I got the vice blocks, but haven't needed them yet. The auto center punch idea is great. I have a couple in the garage so I will grind one down as you said and try it. The method I used for the pivot pin detent was shown on website. After loading in the spring and detent, I used a thin x acto knife to hold detent down and slid the pivot pin in right over the knife blade. I actually dropped the pin on the floor and was able to reach it with my other hand, still holding knife/detent/spring in place!

Welcome to our world! I started my first one in *05, and had 2 more built in the next year. In the last 16 years I*ve built more than I care to count and at this point I build my own with 80% Billet Receivers. Also searched out specific NAMELESS parts from the machine shops who actually make the parts for most suppliers. You*re on your way!

BTW:, grab yourself a 1/4* Clevis pin from Home Depot, Lowe*s, etc. Works like the special tool and only costs $2. Looks like this.