Cast .450 marlin

Justjump

OK I have a .450 marlin guide gun. Had it and dies for years. Like to load a 400g cast gas check. Looked most everywhere no luck. Not hot loads at all just like to shoot the gun some. I tried some loads of SR4759 working off of 45-70 reduced load data. Haven't chrono'd these loads yet. First three rounds using 29grains show no excessive pressure indications. But holly crap they bark!!!!!
Anyone else ever try this?? Any suggestions???
I'll let ya know about V when I chrono a couple tomorrow.

charliemeyer007

So I looked in my Lyman #49 book and it says 30 gr of SR4759 with a 400 gr plain base(I think) 457673 is max. Starting load is 24 gr.

Justjump

Thanks Charlie!!!
Got home to late to check velocity. (dark) I don't have any info on burn rates for sr4759. All info I can find in my old manuals shows it used for large bore reduced loads. Thats why I went that direction. I'd suspect 3031 would be an option, I guess its about time to buy another manual. Last one I got was probably 15 years ago. Before the .450 was out anyway

Justjump

Ok started over and worked up from 26g mild, Ended up at 30g SR4759. 10 pieces of brass loaded 3 times each. I know thats a max load for the 400g gas check bullet. 10shot avg was 1561 fps. Informal accuracy I felt was very good. 5 rounds inside 2 1/2" at 50 yds (braced off-hand, factory iron sights) No excess pressure signs at all. I was hoping to get over 1750. hmmm