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300 blackout subsonic

Herd Thinner

Sergeant
Full Member
Minuteman
Dec 11, 2013
244
2
Pittsburgh PA
Correct me if I am wrong in my thinking but when developing a subsonic round with 220 G and the bolt does not cycle properly the CUPP was not high enough to make that happen ......curious ....I am trying to find a load since 1680 is not easy to find .....
 
H110 will frikkin blow up ur rifle, stick with AA1680 or AA5744 n drop down to IMR/H-4198/RL-7/Norma200 if need be. Try a different spring if its not locking back or get an adjustable gas block to set for sub or super. The JP silent buffer with the white spring can handle both subs n supers.