Yesterday I placed an order for a 22" Contender barrel in Gary Reeder's 257 Raptor which is based on the 204 Ruger necked up and improved (think Ackley). From what I have read it appears this round is very similar to the 257 Kimber. I've got a good quanity of IMR 4064 and I would like to use this powder to fireform the brass and barrel break-in. From my various manuals (looking at 223 Rem, 222 Rem Mag, and 6x45)it appears that 24.0 grains would be a safe fireforming load with 100 gr bullets. What do you think? Please advise. Thank you.

Alan

Off hand it looks like you're in safe territory. In fact the pressure may be a little low to get good fire form. roger

Alan, why are you asking people that for the most part have no idea about this cartridge? Probaby better to go to Garys site and ask the questions, you will get more information about this than anywhere else. There are quite a few there that have this cartridge and have already done much of this homework. I have a lot of Garys cartridges but did not yet aquire any of the Raptors.

Woody

Woody I'm asking because some here may have experience with 4064 in the 6x47, 222 Rem Mag, etc and be able to advise accordingly. I've received the data from Sean and I've PM'ed him regarding 4064 since it is not listed.

Alan

Fire forming with jacketed bullets is, to me, a waste of high dollar projectiles... If it were me, I would prime the cases, charge them with about six grains of Unique, fill the remainder of the case with corn meal (up to the neck), plug the mouth of the case with Kleenex, and fire the "rounds". You should get a perfectly formed case, and you will still have all your projectiles...

Do this with one case to check powder charge, and adjust as necessary.