I can't find much about them but they appear to have good specs.  Is it worth spending $160 on a RCA bolt vs $100 on the Toolcraft?

Or should I just stick with a CMMG?

I'd prefer to find a couple more CMT's, however, they are sold out now it appears.

Grabbed a CMMG and 2 of the Toolcraft bolts to try.

I have a Toolcraft 9mm bolt it works great I only have about 500 rounds through it but so far so good.

Just got my blowback 9mm bolt from them and it was a bitch to install in the dirty upper.

Guessing I need to clean the upper so the new BCG can start out with an in-spec upper before gunking it up.

Seems like my old Model 1 Sales Colt bolt, which was Glock'd by ADCO, is cut differently and keeps the upper "scraped free" of carbon build-up in the spots where it actually rides.

The Toolcraft bolt is cut differently on the face and was encountering a ton of resistance ~1/2" out from contacting the breech face.

Once I have it smoothly hand cycling I'll run it on the DDLES Glock lower with mil-spec FCG to ensure it runs as well as my current set-up before slapping the upper on an SBR'd AR lower with a Geissele SSA, mag block, and Colt mags.

I went with a United Defense Labs BCG. I haven't given it much exercise yet but it a unique quality in its description:

"This Includes excess pressure release holes in the carrier that relieve pressure in case of ammunition failure
to reduce the chance of out of battery firing. This feature has never been seen on any other 9mm carrier."

I don't know if this will ever make a difference, but I figured it couldn't hurt.

If I didn't get this one, my next choice would be Toolcraft. They make great quality BCGs at a great price.