Had a reloading session from hell yesterday. If it could go wrong, break, get stuck...IT DID! (Took two hours to load 23 rounds on a progressive press. Supposed to be 24 but part of a case is still stuck in a reloading die)
Anyway, I learned something yesterday afternoon. We always considered the Blackout/Whisper to be the same and essentially they are. However, be warned. The older 300 Whisper / 300/221 form/trim dies are built for the old standard of 1.400 inches of case length. These will not chamber in a 300 Blackout rifle. (Which requires a case length of 1.368.)
Found this out after my jury rigged case trimmer was irreparably damaged with about 3 cases left to trim. So, I dug out my case form/trim die. No amount of adjusting would allow the shell holder to trim the cases below the 1.400 inch length. (That is short of sending it all out to a machine shop to have the bottom of the die trimmed.).
Anyway, I learned something yesterday afternoon. We always considered the Blackout/Whisper to be the same and essentially they are. However, be warned. The older 300 Whisper / 300/221 form/trim dies are built for the old standard of 1.400 inches of case length. These will not chamber in a 300 Blackout rifle. (Which requires a case length of 1.368.)
Found this out after my jury rigged case trimmer was irreparably damaged with about 3 cases left to trim. So, I dug out my case form/trim die. No amount of adjusting would allow the shell holder to trim the cases below the 1.400 inch length. (That is short of sending it all out to a machine shop to have the bottom of the die trimmed.).
