I'm in the process of building/assembling a big bore AR. I just finished assembling the lower, and some of my mags won't drop free.
NHMTG straight 20 rounders are very snug and will not drop free. I've tried all three of them. However several of my other mags drop free. These include: straight 20 round vietnam era mags, NHMTG 30 rounders, and D&H 30 rounders drop free.
Question is why do 30 round NHMTG drop free and 20 rounders don't? Don't they use simialr tooling in manufacture?
I have to pull the mag from the mag well. Tightness only occurs after mag catch engages. When I disengage the mag catch, I physically have to pull the maga out. I did notice my other mags slightly jiggle in all directions when seated.
I have a Stag Lower also and all mags drop free.
Any hints or other RRA lower owners with same issues. Oh, these are marked resticted and dated 3-02?
I found the problem. My trigger guard from my LPK is to large. The radius at the front of the trigger guard is higher than the groove in the rear of the mag well. The rear mag rib/seam rubs against it the radius of the trigger gaurd.
I compared it with my stag lower which has a different brand LPK and the radius sits below the groove.
Time to find a replacement trigger guard. hinking.gif