Quote Originally Posted by gandog56 View Post
Took the AR to the range today. After warming up with about 50 rounds of .223, I pulled off the 5.56 upper and put on the .300 AAC Blackout upper. Only had forty rounds to fool with it and the only sights was a variable scope I had laying around. Fortunately I hit the paper first shot and it wasn't too far off. About 10 rounds put me dead nutz on at 50 yards. Moved it out to 100 yards but I didn't hit paper, was shooting high. I ran out of ammo before I got it totally zeroed in. Seems like a fun round, but the darned thing slam fired on me about 4 times in that 40 rounds. (all four times let loose two shots) Not sure what to do to fix it.
use primers #41, they are a bit thicker on the cup so a firing pin needs to hit hard to set it off.

just one of many sources

https://reloadingunlimited.com/produ...rifle-primers/


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