Hi, i just finished building my 9mm ar, i used a Spikes Tactical 9mm lower and an Aeroprecision 10.5 inch upper with a KAW 9mm BCG and colt mags. The issue i am having is that when the bolt goes back and ejects the spent shell it moves the next round in the mag out of position thus creating a feeding issue. It either leaves that next round almost out of the mag or too crooked to be able to feed right into the feed ramp and chamber. Looking for some advice, Thank You!
9mm ar15 feeding issues
- Thread starter The Biker
- Start date
Yes, according to the manufacturers everything is supposed to be compatible, the lower is strictly for colt mags and the BCG takes either Golck or Colt mags. I might just try different colt mags to see what happens.
the obsrver
Master Class
Sounds like a mag or feed ramp issue.
What is your buffer weight?
9mm AR's typically need a 7oz to 10oz buffer to run reliably otherwise the bolt cycles too fast and feed issues can happen.
There's a fine balance with the 9mm bcg weight and the buffer weight that needs to be taken into consideration.
Also using an AR10 buffer spring is very helpful as a typical AR15 spring won't supply enough resistance to the blow back action.
As you most likely already know an AR9 is a direct blowback system that doesn't use a gas impingement system not does it use locking lugs like a typical AR-15 so it has a greater recoil force that needs to be countered.
9mm AR's typically need a 7oz to 10oz buffer to run reliably otherwise the bolt cycles too fast and feed issues can happen.
There's a fine balance with the 9mm bcg weight and the buffer weight that needs to be taken into consideration.
Also using an AR10 buffer spring is very helpful as a typical AR15 spring won't supply enough resistance to the blow back action.
As you most likely already know an AR9 is a direct blowback system that doesn't use a gas impingement system not does it use locking lugs like a typical AR-15 so it has a greater recoil force that needs to be countered.
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