.45 AR pistol issues

Posted by: magchange

.45 AR pistol issues - 08/17/20 01:32 PM

Maybe an expert or 2 can help here.My son built a 45 7" pistol that fails to feed and eject every other round basically.the spring /buffer is a 45 cal and it's not a magazine or Ammo issue all have been tried.The lower is Wolfpack armory and upper is delta team tactical.If this thing ever gets fixed it will be a cool little weapon but just a heartbreaker for him now.The thing I can't get past is no feed ramp?.is that normal for a sub gun?Feel free to chime in-thanks
Posted by: LaserJock

Re: .45 AR pistol issues - 08/17/20 09:21 PM

Blowback?

You need a small chamfer on the chamber face

I've used 1 inch diameter grinding stones chucked into a drill. Final polish wrapped the stone first with 80grit then 120grit then 220grit and finally in steel wool

Pic stolen from the web. Mine was more of a radius rather than flat

Posted by: Builder_Zee

Re: .45 AR pistol issues - 08/21/20 11:15 PM

Sounds like a neat little build. The failure to eject leads me to suspect a timing issue. A direct blowback build will, by necessity, need a higher buffer weight. Recommended weight is 10 ounces; you can use either an adjustable weight buffer or fixed weight as offer by Kaw Valley Precision.
Posted by: Builder_Zee

Re: .45 AR pistol issues - 08/21/20 11:16 PM

Sounds like a neat little build. The failure to eject leads me to suspect a timing issue. A direct blowback build will, by necessity, need a higher buffer weight. Recommended weight is 10 ounces; you can use either an adjustable weight buffer or fixed weight as offer by Kaw Valley Precision.
Posted by: magchange

Re: .45 AR pistol issues - 08/22/20 11:23 PM

Thanks for the input guys .He took it to Middletown firearms out in Winchester to save time.They discovered issue with the trigger pack and a burr in the lower i think.My son said the gun went full auto on the guy with a extended glock mag.They replaced trigger pack and couple things for $200 and contacted ATF i believe to see if anyone else has a possible automatic weapon.Live and learn-haha
Posted by: Newgunguy

Re: .45 AR pistol issues - 08/22/20 11:55 PM

My 9mm upper from Davidson Defense also didnt have a feed ramp and I was having all kinds of issues with the projectiles being rammed down into the cases. My problem was the mags and it runs fine with a Joe Bob's Spartan lower for Glock mags.

Charles.
Posted by: magchange

Re: .45 AR pistol issues - 08/28/20 11:38 PM

Thanks for that info he actually is still encountering that same issue.Wasting .45 ammo testing it is driving him nuts.Not sure what route he's going to go.I told him don't get Korean/sgm mags stick with oem glock but live and learn.Hes going back to the gun shop since he already paid them hopefully they figure it out...ugh
Posted by: LaserJock

Re: .45 AR pistol issues - 09/01/20 07:30 PM


Ran about 25 to 50 rds of ball ammo thru CMMG radial delayed blowback 8" barrel and bolt combo. Upper, rail charge handle etc was just a spare leftovers set of parts. No sights, no muzzle device laugh 1 minor hiccup in the beginning

Bolt locks back on the mag follower

Quarter Circle 10 lower
Posted by: Rogpog

Re: .45 AR pistol issues - 11/03/20 11:50 PM

I have a ar45 and I had to cut a little bit more geometry on my feed cone. Pm me and I can send a video of what I did