3 year Study results of QCB Upper & Grendel

[LRRPF52]

If you mean another Gen III or IV MGI upper, I'd rather not, since I don't like dedicated quad rails. That's why I jumped on the Gen I upper, and then machined off the 3 & 9 o'clock rails to make it more streamlined. I also ordered their rifle-length handguard extension, and contoured down the locking channels where they protrude from the tube. I then Cerakoted everything in Coyote Tan.

I'll have to post some pics of it when I get a chance.