New rifle build has feeding issues

[Langenator]

It took me forever to get all the parts, I finally get to run it in a match, and on the second stage it refuses to feed.

Specs:

Aero Precision upper w/M4 feed ramps

Nordic 18" barrel

Seekins LW BCG

JP Silent Capture buffer spring assy in a rifle buffer tube.

During test fire and getting the scope zeroed, I fired 20 rounds with no problems. First stage of the match, 28 rounds, no issues.

Second stage, with 3 different mags (2x 30 round PMags, 1x 20 round Lancer), the rifle would not feed the rounds into the chamber. This was starting with the bolt to the rear, using the bolt release. Rounds were stuck at an upward angle, like they snagged on something or there was too much friction somewhere in the feed path. Unfortunately, I didn't get any pictures.

I tried to duplicate the problem at home and haven't been able to. Most of the time, the bolt group just stops about 1/2" shy of going fully into battery. About 1 try out of 4, it will go properly into battery.

Part of me wonders if the JP spring assy and the Seekins BCG aren't a happy combo.

Or maybe I just need to lube the snot out of it and take it to the range to run 100 rounds or so through it to get it broken in.

Thoughts?

[Hi-Power Jack]

Reloads?

[bwikel]

What ammo are you shooting? It not going into battery could be your ammo or short stroking or several other things.

Edited May 16, 2016 by bwikel

[blairmckenzie1]

Is the gas block adjustable or fixed? Is it tight and lined up right?

[Dan Sierpina]

Lube the snot out of it!

When an AR doesn't want to feed, when it previously did, squirt some lube into the holes on the side of the bolt carrier, work it back and forth a few times, then more lube. It's a new bolt, and carrier, most gas rings have some roughness on the outside diameter from the stamping process.

For some reason, I prefer to charge with the bolt down, and then work the charge handle to strip the first round. Just something to try.

[Langenator]

It's factory (Freedom), but that wasn't the issue. It wouldn't feed to start - either with the bolt locked to the rear and released with the bolt release lever, or when inserting the mag with the bolt forward, and then racking and releasing the charging handle.

It never had a change to be a gas/ammo issue, because the rounds never made it into the chamber to be fired in the first place.

[soterik]

I was going to say it isn't getting enough gas. Open up the GB a couple clicks. Happened to me over the weekend at Regional.

Then you said it wouldn't even feed when using charging handle. Can you try a stronger spring on your JP SCS?

[Chip3]

Does the bolt go into battery without the mag inserted? May check that to see if something is hanging up. If you have another ar, swap lowers and then maybe bolts. Using the two guns may help you track down where the issue is.

[dauntedfuture]

take your BCG apart and take the CH out of the upper. Insert the BC and see if things are binging in or around the gas tube. About 1/2 from closed is where the gas tube starts to go into the BC gas key.

[Stlhead]

Have you tried scotch? Enjoy a couple of fingers before you try a conventional buffer spring and reduced weight buffer. I do not think the Seekins bolt carrier plays well with the captured spring.

[BradfromND]

Did the gas key move on the bcg and causing a bind? Make sure the gas block didn't rotate and cause the tube to angle into the receiver and bind up on the gas key.