Powder for 338 LM improved? H1000?

[COHotshots]

Need some help on magnum powders as I seem to never be able to find any powder available. I first tried retumbo (Over 3000 FPS,15-20 spread) then that went extinct before I could really dial that in. Then 8133 (2785 fps, 6 es) and now I can’t find any for the last several months. What powder should I try next? From what I’ve read RL33 is temp unstable but read that some people are getting decent results with H1000. What do you guys think about H1000? Temp stability? Consistency? Cleanliness?
338 Lapua improved
26” barrel
COAL 3.950
Berger 300 otm
Running 338 ultra suppressor as well

 

[dave300]

N570
Retumbo
RL33 (yes, reported temp sensitivity)
In other calibers I have had great results with H1000, stable, consistent and cleanliness are all good. It is a bit faster on the burn charts than those that I mentioned.

 

[COHotshots]

Sounds good thanks. I might give 570 a try after reading more about it. Is it clean and stable as well?

 

[Deleted member 113831]

To ensure an adequate supply to feed that gun for the life of the barrel, you need to buy at least 20lbs at a time.

 

[dave300]

Sounds good thanks. I might give 570 a try after reading more about it. Is it clean and stable as well?

Yep!
Good luck on sourcing it though. It just hit the usual supplier a couple months back, hard telling next time it’ll be available

 

[COHotshots]

To ensure an adequate supply to feed that gun for the life of the barrel, you need to buy at least 20lbs at a time.

Yeah unfortunately the problem is finding a few pounds at a time for any magnum powder.

 

[swampbuck]

I don't think H1000 will be any easier to find

 

[dave300]

I don't think H1000 will be any easier to find

Much easier, in stock at Brunos and has been. Same recently at some of the same ol haunts

 

[Safety_3rd]

You guys mind posting any of your load data? obviously I'll work my way up, just curious what you guys settled on.

 

[1moaoff]

H1000 is stable and cool burning
Rl26 will make it go faster

Both can be found in bulk if I walk to my reloading room

 

[BCX]

RL-33 is all i have used in my 338 LM AI. Haven't had any temp sensitivity. Will try N570 if i can ever find it.

 

[dave300]

You guys mind posting any of your load data? obviously I'll work my way up, just curious what you guys settled on.

100 Grains of N570
lapua brass
Berger 300 otms
215M primers
Jumping them .035

 

[TheBoctor]

You guys mind posting any of your load data? obviously I'll work my way up, just curious what you guys settled on.

Here are some of mine:
Lapua Brass
Berger 300 Elite Hunters
GM215M
Jumping .020"
24" 1:9.4 proof
102.0gr N570 @ 2909fps
108.2gr RL33 @ 2893fps (compressed)
99.2gr Retumbo @ 2902fps
96.3gr RL26 @2910fps (never really found a node)

The N570 is by far and away the best powder of the bunch.

 

[Safety_3rd]

Thanks guys... headed to the range now to fire form... then the real fun begins (and the search for powder)

 

[Quicksilver338]

N570 first pick, try n565 also, retumbo, imr 8133, h1000 in that order otherwise.

 

[Dogtown]

N570 and RL33 have been my go-to powders for this cartridge. Unfortunately, both are hard to find at the moment.

 

[Quicksilver338]

When you can find it buy plenty! I git 22lbs of 570 and 20 of retumbo for that very reason.

 

[BCX]

Have plenty of RL-33 but still trying to find N570. Happy w RL-33.