Made up a few test pieces of .300 Fireball/Whisper/.300-221 using Guatemalan 5.56 brass in a Redding die. The piece below is sized and ready for loading. All my other brass from SSK and Keith Davis measures .329 to .330 on the sized necks. With the Guat brass they run .334 to .335 Is this too large?
Wow thats a thick walled case if its reading .334 without a bullet seated. Seating a bullet will usually increase the neck diameter a couple of thou making it .335 -.337 which means it wouldn't even chamber in my 300/221s, would be a press fit in a 300 whisper but possibly could be shot in my 300 fireball although I would probably pass on using it since ARs like a little clearance for proper functioning.
I'm not sure what the spec is on the outside diameter but I do know the Portugese .223 brass is so thick that it won't fit any of the chambers we have here. Actually it won't even fit in the seating die unless we neck turn it....
Maybe the guatamalan stuff is the same. Military stuff with heavy brass for military use...
Where did you get this brass? I am wondering if it my be good stock to use and turn the necks down to make them really uniform? Anyone have a thought on that?
Wideners had this brass awhile back for $100/1k shipped. I picked up a bunch and have used it with good success for my .223 loads. It is brand new/never fired brass.
I actually loaded a few dummy rounds and tried hand cycling them through my Noveske .300 FB barrel. No problems so I loaded up a few to test fire. Again, no problems. Loaded neck diameter was .336