"1"^^ . . "2016-05-10T00:00:00"^^ . "0"^^ . . "I bought a 308 lower from Quentin Defense and began an 18 month journey to try to get a functioning gun together. Supposedly their stuff is \"DPMS pattern\", but no DPMS uppers work with their lowers. I went to DPMS and tried a handful of uppers on, then they pulled out a carton of stripped uppers and I tried on 10 or so of them with no luck. Couldn't even push the pins through.\n\nI brought my Quentin Defense 308 lower receiver to gun shows over the next few months and tried different uppers on it. I tried 20 or so uppers with no luck. Some didn't fit, some didn't line the bolt up with the buffer tube, and some had a conflict with the bolt release.\n\nI gave up this past Friday, went back to Quentin Defense and tried to get an upper built. They talked me out of it and into a prebuilt upper they had on the shelf. I noticed it was well used, but sold to me as new. I figured it was no big deal, I'd finally have the thing working. I went to put my silencer on and couldn't. I tried another one, no luck. I took a look at the muzzle threads and shoulder area. Don't drink and lathe. There is no shoulder on the muzzle for a muzzle device. There are a series of bulging tapers that prevent muzzle devices from being used. Also the crown is a weird, deep 45 degree cut.\n\nI returned the upper and sold them back the complete lower for $50 because I couldn't in good conscience sell it to anyone. The lower won't work with anything but Quentin Defense uppers, and those either don't work or don't exist. I wasn't going to sell that lower and force somebody to buy a Quentin Defense upper. There are like 30 alternatives and any one of them will work."^^ . . "1"^^ . "5"^^ .