US869 in the .300 RUM

[Overkill338]

Have any of you tried it and will it work with 225gr ELD-M? It's the only powder I have found that MIGHT actually work.

Thanks

 

[Jud96]

It's very unstable.

 

[Overkill338]

It's very unstable.

I had my fill of unstable with a .338 win mag. Had a great 1/2" group load in the winter and a stuck bolt in the summer.

 

[Jud96]

Yeah US869 is not temp stable at all. I would try and find something else but unfortunately in today's market finding reloading powder is nearly impossible.

 

[P7M13]

I was thinking you wouldn't get the velocities you were after, but this seems to indicate otherwise:
From the Accurate Shooter Forum :

US 869 powder in a .300 RUM

Edit to add, I think temperature stability concerns are overblown. It is an important consideration if you go from death valley to snow capped peaks in the same day, but it shouldn't matter because if you are at that level of performance, you have already worked up your dope at different temperatures and elevations.

 

[alcesgigas]

US 869 is the easiest handling, finest weighing, and tempermental powder I've ever used. It proved the most accurate powder in an edge and Terminator; haven't used it in my 338LMAI. Someday I'll get there along with N570.

 

[whirlwindjml]

It might keep you in the fun till the powder flows again! If you have it try it

 

[BallisticsGuy]

I like it a lot in 7RM. It responds to temperature changes more than more modern powders. Dirty as heck but meters like water and does well in really overbore cases.

 

[79m1a-texas]

I tested US869 in a 300 WM. Pass on it to try better powders.

	US869		Primer	Average	SD:	ES:
US869	83.0	208 ELD-M	Fed 250M	2562.7	10	19
US869	83.3	208 ELD-M	Fed 250M	2576.7	13	22
US869	83.6	208 ELD-M	Fed 250M	2572.0	12	24
US869	83.9	208 ELD-M	Fed 250M	2609.3	14	26
US869	84.2	208 ELD-M	Fed 250M	2594.7	13	23
US869	84.5	208 ELD-M	Fed 250M	2615.7	13	24
US869	84.8	208 ELD-M	Fed 250M	2628.7	17	33
US869	85.1	208 ELD-M	Fed 250M	2628.0	18	34
US869	85.4	208 ELD-M	Fed 250M	2657.3	10	20
US869	85.7	208 ELD-M	Fed 250M	2672.0	18	32
US869	86.0	208 ELD-M	Fed 250M	2703.3	41	75

 

[Dosh]

Tried it in my 30/378, best group I've ever had at 500 yds. The weather warmed here in Az and the group went south. Quite unstable in my opinion.

 

[idcwby]

Would it be a good one to work up when it's warm and than see how it does when it cools down?

 

[Lefty7mmstw]

have you found either rl33 or rl50? I am running either in my 300 rum's with the hdy 225 hpbt and they both run 3,000 fps with ease. I'm at 95 gr rl33 in rp brass/ 215 primer... 102 rl50... same brass/primer
both seem pretty temp stable to me in this loading...

 

[Overkill338]

have you found either rl33 or rl50? I am running either in my 300 rum's with the hdy 225 hpbt and they both run 3,000 fps with ease. I'm at 95 gr rl33 in rp brass/ 215 primer... 102 rl50... same brass/primer
both seem pretty temp stable to me in this loading...

Yes, 50 is in the same store as 869. I was thinking 50 was too slow so I didn't even consider it.

What length barrel?

 

[Lefty7mmstw]

Yes, 50 is in the same store as 869. I was thinking 50 was too slow so I didn't even consider it.

What length barrel?

normal 26" factory on both rifles... The load will be a bit compressed but a bit of vibration or tapping on the case should get it in fine. I'd start in the mid 90's and work up for rl50 with a 225 in a 300rum.