CMMG upper issues

[RocketmanOU]

With the lack of commercial rounds available and cost for what is.....that is an extremely poor stance to take. That marks CMMG off my list of potential uppers.

Me too. I will be putting together my second 300BLK this year and was considering them, NOT AFTER THIS. CMMG, I want you to understand that it is not that you had a problem (as those things happen) but it was your total lack of customer service.

+1. Went with a different brand.

[L1A1Rocker]

With the lack of commercial rounds available and cost for what is.....that is an extremely poor stance to take. That marks CMMG off my list of potential uppers.

Me too. I will be putting together my second 300BLK this year and was considering them, NOT AFTER THIS. CMMG, I want you to understand that it is not that you had a problem (as those things happen) but it was your total lack of customer service.

+1. Went with a different brand.

Just got my PSA kit yesterday. Hopefully I'll have time to get out to the shop this afternoon and put it together.

[Maryland_Shooter]

With the lack of commercial rounds available and cost for what is.....that is an extremely poor stance to take. That marks CMMG off my list of potential uppers.

Agreed, if you talk about a load that blew up the thing, that's a horse of a different color.

As it is, WE are getting shoddy 300 BLK uppers and these folks (CMMG isn't the only one) are just using any dodge they can to stick you with a defective product.

They'll kill the round's future if it continues.

Make 'em pay. Vote with your $. When they have no customers, they'll be forced out of the 300 BLK market.

[Maryland_Shooter]

This drawing certainly explains A LOT! Very much appreciated.

I wished I had taken the gas key out before I re-staked the screws. I feel very compelled to take it apart and perform this procedure, that is, unless by doing so I mess the gas key up and then it won't re-stake correctly the next time.

Dude, not done the thread, but buy 2 grade 8 screws to use. Many times the torque wull shear the heads off. Spend $5 and get 2 new ones. Grade 8 . . .

[Maryland_Shooter]

Now, this isn't the first time I've seen threading issues from CMMG (a friend had issues with a 5.56 upper) but that said, I've had pretty good luck with their CS. My guess is the reason they said no on the return for service was because he opened up the gas port (which I probably would *not* have done before I sent it back to them for a look over).

This is not a new issue with CMMG. Bores are often not concentric to the barrel . . . and threads are often really poor.

ADCO, at one point, simply refused to work on CMMG barrels. Ask Steve at ADCO, he'll tell you all about it.