I had a Stainless New M-70 chambered in 340 Wby with a 26" Benchmark #4 fluted barrel in a B&C stock (like the Extreme Weather M-70 stock). With Barnes 225 TTSX I was getting 2975 fps with RL-17 and 2915 FPS with H4831SC. 100 yds three-shot groups were averaging an inch but would occasionally open up to 1.5". That isn't terrible and didn't really affect the utility of the gun, a 8.5 lb elk rifle for carrying around, but I like 3/4" groups at 100 yds from big game rifles.
So it was just a matter of time after I got my lathe that I would try something different on this action. I got the rifle finished a couple days ago. I went with a 26" Benchmark #4 non-fluted barrel (fluting a #4 only saves 2 ounces), the same action, and same stock. I ran a 33 Nosler reamer in another .150" until it headspaced off a 26 Nosler go gauge. I put a 4.5x14x40 AO vs the 3.5x10x40 and my 33-28 Nosler rifle weighs 8.75 lbs w/scope.
Making the cases wasn't terrible. Start with 28 Nosler cases. Neck up to 30 cal in Whidden 300 WSM die (for my BR rifle). It has a nice tapered expander. Then run through an RCBS 325 WSM die. Then size in the 33-28 Nosler bushing die I drilled out. The only issue was the bottom of the neck was .006" larger than the top due to the neck expansion bringing the shoulder up, so I had to neck turn that bulge off.
My best group today was 84 grains of RL-23, just under 3/4", 3058 fps. That was not a max load, but an unbraked 8.75 lb 338 starts to really pack a wallop at 44 ft lbs of recoil. Yes, I have shot bigger rifles with more recoil, but the 375s and 416s give more of a push while the big 338s give a hard snap which takes more getting used to. Besides, I have been shooting almost exclusively 17 lb BR rifles for the last two years.
I really don't want to use my RL-23 in this rifle, as that is the powder my 300 WSM LR BR rifle loves. I am having a hard time deciding which powder to try next. Reasonable choices are: H4831SC, IMR 4955, H-1000, or RL-26. Then again, it's not like I will be shooting THAT much RL-23 in the 33-28, and with the ability to adjust seating depth (unlike with the 340) I have a lot of room to keep tuning.
Thoughts on powders?
So it was just a matter of time after I got my lathe that I would try something different on this action. I got the rifle finished a couple days ago. I went with a 26" Benchmark #4 non-fluted barrel (fluting a #4 only saves 2 ounces), the same action, and same stock. I ran a 33 Nosler reamer in another .150" until it headspaced off a 26 Nosler go gauge. I put a 4.5x14x40 AO vs the 3.5x10x40 and my 33-28 Nosler rifle weighs 8.75 lbs w/scope.
Making the cases wasn't terrible. Start with 28 Nosler cases. Neck up to 30 cal in Whidden 300 WSM die (for my BR rifle). It has a nice tapered expander. Then run through an RCBS 325 WSM die. Then size in the 33-28 Nosler bushing die I drilled out. The only issue was the bottom of the neck was .006" larger than the top due to the neck expansion bringing the shoulder up, so I had to neck turn that bulge off.
My best group today was 84 grains of RL-23, just under 3/4", 3058 fps. That was not a max load, but an unbraked 8.75 lb 338 starts to really pack a wallop at 44 ft lbs of recoil. Yes, I have shot bigger rifles with more recoil, but the 375s and 416s give more of a push while the big 338s give a hard snap which takes more getting used to. Besides, I have been shooting almost exclusively 17 lb BR rifles for the last two years.
I really don't want to use my RL-23 in this rifle, as that is the powder my 300 WSM LR BR rifle loves. I am having a hard time deciding which powder to try next. Reasonable choices are: H4831SC, IMR 4955, H-1000, or RL-26. Then again, it's not like I will be shooting THAT much RL-23 in the 33-28, and with the ability to adjust seating depth (unlike with the 340) I have a lot of room to keep tuning.
Thoughts on powders?
