05-28-2012, 01:38 AM
I get scrapes on the projectiles on all my AR's, including the 5.56 carbines, and my .260 Rem AR10.
The clock position for your brass location seems fine. When it gets to either extreme is when you're having non-optimal timing of the operating system-either too fast of a cyclic rate, or too slow. Too slow usually comes along with too short, and doesn't lock the bolt back, and stove-pipes the spent case as well. This is more rare in the AR than too fast-a common occurrence with long dwell times, and early unlocking. That's when you see the 1:30 or even 1:00, with the case barely making it out far from the receiver.
The cases should be ejecting about 4ft from the rifle.
The clock position for your brass location seems fine. When it gets to either extreme is when you're having non-optimal timing of the operating system-either too fast of a cyclic rate, or too slow. Too slow usually comes along with too short, and doesn't lock the bolt back, and stove-pipes the spent case as well. This is more rare in the AR than too fast-a common occurrence with long dwell times, and early unlocking. That's when you see the 1:30 or even 1:00, with the case barely making it out far from the receiver.
The cases should be ejecting about 4ft from the rifle.