458 socom 420gr

[Al_Bundy]

Need help with this Lee boolit using RL7, registration on the 458 socom forum is not working so I'm trying several other forums. Found lots of data for 300gr and 500gr but 400gr is scarce. So far I've found some loads maxing out at 25gr of RL7. I do have Unique as well as varget and some 3031 but i have 8lbs of RL7 that i'd like to dedicate just for the socom. I'd be open to using the lee 340 mold or stocking up on lil gun if thats more beneficial but keep in mind i dont want to push these hard because they are powder coated and i want to avoid gas checks as well as not have too much recoil because this load is for my 60yr old dad. Im thinking somewhere around 1500-1600 fps should be pretty tame push on recoil.

16" barrel will be used, starline brass, S&B LPP, 420gr pc cast lead.

[DDriller]

38 grains Rel 7 with a 405 gr bullet is around 1600 fps

[Al_Bundy]

38 grains Rel 7 with a 405 gr bullet is around 1600 fps

is that a 405 plated, jacketed, lead bullet you're referring to? And if you mind, where did that data come from? I appreciate the help Driller

[DDriller]

That is with either jacketed or lead. Less than 20fps difference in velocity.

[ThaDoubleJ]

If you do some searching around, either here or on the 458 forum, you'll find my 4" groups at 50 yards with that Lee 340 mold. I just sold it, nothing I could do would bring it to acceptable levels of accuracy from my 12" AR. Hornady FTX 325s make a cloverleaf at the same distance and load.

[WehrmannsGeweher]

Had the same problem w/450 Bushmaster AR and cast, 4" @50. Works fine in Ruger bolt gun. Was told ARs have gain twist, maybe SOCOM too ?