Great barrel, 4150 crmov - FM Products Ultra Premium Match Grade Glock Barrel

I was looking for a decent barrel for a new Glock build. I really wanted to avoid a stainless steel barrel as there was an intention to use high pressure ammunition (Underwood +P+). I wanted 4150 CrMoV, but flush fit unthreaded.

I dropped the barrel into a Cerakoted Hooper Gun Works slide. Unfortunately, I couldn't get the thing to lock up correctly. My Faxon barrel fit and functioned correctly. After taking some measurements, it appeared to me that the FM barrel was in fact out of spec by a few thousandths on the ledge of the barrel hood.

I stoned the ledge for about 3 hours, going nice and slow. Once I got a good lock up, I blued the steel where the finish was removed, and now it looks and works perfectly.