i have a 14" stainless MGM .30reece. It has become my favorite small plinking round.
case capcity is slightly above the 32/20, a bit less than the 300 whisper. You can use standard .357 mag brass to form cases in a single pass through the sizer die, though you will have to trim a few thousandths off. i used .38 special instead, so probably wont have to worry about ever trimming. Even using .38 brass, the case neck length is more than adequate.
Carson Reece sells the dies (Hornady), seems like i paid about $35, and also has formed & properly headstamped cases if you prefer to buy them. he is a pleasant fellow to work with, and also gave me booklet of loada data tested in 10", 15", & 24" barrels.
The TC custom shop is chambering for the round as well.
Carson's load data reported the following with 110 grain Hornadys out of a 15" tube:
17.5gr H110....2242.0 fps
17gr 296.........2121.7 fps
14gr 2400.......2090.8 fps
14gr AA#9......2035.2 fps
16.5gr H4227...2003.1 fps
10.5gr Blue Dot..1856.9 fps
My MGM tube gives 3-shot cloverleafs at 50 yards, and shoots sub-1" at 100. I also found mine really likes the hornady 90 grXTP, and would guess velocities at 2500 or so, havent clocked them yet. Hodgdon's Lil Gun has given some very good grups, though it seems to like most evrything i have fed it so far. I plan on having a carbine made up as well.
If you call Kerry at MGM he will make you a great barrel, the last few barrels i've ordered from him have averaged a 6 week production time or so.
Hope the info is of some use.
Regards;
Gerald
