GG&G Upper Problem

[USMC Tanker]

I have a GG&G Dominator-1 upper and a complete CMMG bolt carrier assembly, I've never fired my AR. I was having a VERY hard time getting my BCG to go into battery. Once I got it to go into battery, I couldn't get the bolt to retract. I literally had to put the muzzle on the floor, butt stock to my chest, and PULL on the charging handle to get my bolt back.

I initially thought the bolt was the issue. I separated the bolt from the BCG and the bolt slides easily into the chamber area. Not a bolt issue.

I then slid only the BCG in and out of the upper. It feels as though the gas key is possibly getting hung up on the gas tube extension. The BCG slides freely until it get hung up on something about 2/3 of an inch from being in battery.

What should I do?

[spamsammich]

Are you sure your BCG is assembled properly? Is the extractor facing the right side of the gun, the same side as the groove in the BCG? Are you riding the charging handle home or letting it go completely?

If you want to check for gas key alignment you can clean off the gas tube really well and mark it or the inner diameter of the gas key with sharpie. Then cycle the BCG a few times to see where the rubbing occurs. You may need to bend your gas tube to get it properly aligned.

[Cagemonkey]

Inspect the Carrier key for straitness or burrs. Next look to see that the Gas tube isn't bent. Also look at the position of the Barrel Nut Notches. I've seen people install the Gas Tube without the Barrel Nut Notches being alined with the hole in the receiver for the Gas Tube. Could also remove the Gas Tube and try to insert the BCG in the upper with the Charging Handle.

[USMC Tanker]

Thanks for the advice fellas, I'll see!

[CarlosDJackal]

Also, how is the alignment between the upper and the lower receiver? Is the receiver extension tube snugged on properly (check for wobbling).

Goodluck!!

[USMC Tanker]

It wasn't a problem with the upper.

My gunsmith took a look at it, and it turns out my BRAND NEW BCG from CMMG had a bent gas key.

Go figure...

[Cagemonkey]

It wasn't a problem with the upper.

My gunsmith took a look at it, and it turns out my BRAND NEW BCG from CMMG had a bent gas key.

Go figure...Glad to see you got the situation all squared away. Are you going to replace the key? If not buy a FA bolt carrier from Bravo Co.

[USMC Tanker]

My smith replaced the key, it works fine now.

What's the deal with the FA carrier?

[Cagemonkey]

FA bolt carriers are a little heavier than SA bolt carriers since material was not milled out so as to prevent the carrier from working with the auto sear. The extra weight of the FA carrier can help improve reliability due to greater inertia. This can increase bolt dwell time (keep the bolt locked longer) and increase the force of the BCG for feeding and chambering. The effects are minimal and many will probably say its inconsequential.