Alliant Pro 4000-MR & the 300 win. Help!

[Iamero]

Hey guys, from the research I did on this powder it looks like it is almost identical to RL-22 in burn rate, and just a hair faster than H1000.

I came across a screaming deal on 10lbs of it so I couldn’t say no. Well through the order of things I ended up with a 300 Win mag again and want to do some load development.

Keep in mind I am launching these out of a 1:7 twist 30” barrel. Wondering if I should use a slower powder like Retumbo. I tried to push a 220 SMK and 208 Amax with h4350 and it showed poor results.

Anyone have load data for 208-220gr pills and 4000-MR?

 

[culater]

I would try a heavier bullet like the 225 ELD, 230 Berger,and the 240 SMK with your twist rate. Go with Retumbo or H 869. I would try a Warner bullets. May I ask WHY do have 1-7 Twist for your 300 Mag. A 1-9 twist would have work out better for you.

May we see your groups at 100 yds. Maybe we can help. As far as load development you shouldn't have bought that much powder before you found the load for it.

 

[Iamero]

Ehh for $10/lb I was fine using that much. I have a 1:10 twist that shoots 190s and my buddy has a 7mm mag we can use it for if all comes to worse.

Got it on trade. Didn’t think the twist rate was right at first but the guy I got it from said that’s definitely what it is. He only shot the 230 Berger out of it; I just didn’t have anything over the 220 SMK on my bench at the moment.

 

[culater]

Do you have any load data from the previous owner? That would cut your time on finding a load for it.

 

[Iamero]

Yea but I’m not shooting the 230 Berger. Too rich for my blood haha.

 

[supercorndogs]

I could only get about 2700fps out 4000mr and the 220 nobler CC before I started having pressure problems. I tried it in the 6.5 creedmoor, 22-250 and 300wm. I didn't have much luck with it.

 

[Iamero]

Do you prefer H1000 or Retumbo for those heavies?

 

[supercorndogs]

I never used either. I ran 4831sc until my first barrel burned out. I worked a load for this one with the 200ELD and 4831SC, and I was just starting load development with 7977 and the 208 a max. Then I got side tracked working up loads for a new AR barrel, and two new 6.5 creedmoor barrels. I have a length test waiting to shoot. I haven't chronoed or shot groups at range with 7977 yet.

 

[Iamero]

Gotcha. I have a shit ton of H4350 for my 6.5 creed on the shelf as well but my understanding is that is too fast of a powder for the length of barrel and weight of bullets I am launching. I could be wrong on that though.

 

[supercorndogs]

4350 would be optimum. I know Aimsmall55 had some 4000mr 300wm load data. He had pretty good luck with it too, if I recall correctly. I saw him post the other day.