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Is there something undesirable about imr 4831?

I was doing some initial loads for a new rifle today. Loading AB 160's in 280AI. I was using the Nosler manual to load pressure test loads in 1 grn. increments. Started with H4831SC and the loaded some IMR4831. Also finished up a pound of IMR4350 and will run H4350 once confirm the loads. We will see what the results are when I get to the range. No worries right now about pressure spikes due to high temps outside. The manual shows best velocity with IMR4831.
My accuracy never suffered with either powder, but for the same load I get better velocities with the IMR. I push the SAUM pretty hard just for the fun of it so the IMR works better for me when it comes to case capacity. I prefer to keep capacity as close to 100% as I can when I get to the sweet spot without too much compression. Both shoot really well.
 
I'm tough in the cold and a complete and utter baby in any kind of heat haha. You can always dress for cold weather but there's a limit to how naked you're allowed to be in the heat 🤣
You may be able to dress for Ft McMurray in Jan.........I cannot! I don't own enough clothes! If it wasn't for the oil field workers loaning me clothes, I would have died there!
 
I was doing some initial loads for a new rifle today. Loading AB 160's in 280AI. I was using the Nosler manual to load pressure test loads in 1 grn. increments. Started with H4831SC and then loaded some IMR4831. Also finished up a pound of IMR4350 and will run H4350 once confirm the loads. We will see what the results are when I get to the range. No worries right now about pressure spikes due to high temps outside. The manual shows best velocity with IMR4831.
I've been there.
IMR worked sweet in my 280AI... at load development time anyway.
I'm at 60' above sea level with extreme temp swings.
I always developed loads when hot.
Printed dots. Dope right on.
Go out for hunting in dead winter cold OR hunt at 10,000 ft in Colorado... you'll have a change in POI due to temp and/or altitude.

Switched to "H" and solved most of these issues.

Run a short barrel and the games really begin! 😂

It was 85 degrees and humid a couple of weeks ago in South LA when I left to go hunting in Missouri. Upon arrival in 20 degrees I had a dam near perfect zero when I test fired to check zero.
 
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Ive tested quite a bit with 4166, 4451, and some 4955. What i learned was they pressure out suddenly and always, just before that, the groups tightened up. As odd as it may sound. A shame the enduron line was dropped. 4166 was one of my favorite powders. May go back to a few imr powders.
 
Ive tested quite a bit with 4166, 4451, and some 4955. What i learned was they pressure out suddenly and always, just before that, the groups tightened up. As odd as it may sound. A shame the enduron line was dropped. 4166 was one of my favorite powders. May go back to a few imr powders.
Yes I'm sad about that too. Big fan of 7977 and 8133, and they didn't seem so abruptly spiky as the faster ones
 
When I work up my elk loads for Wyoming it may be in the 95F range here in the desert so I put them in a cooler on ice overnight then in a cooler at the range, about a 66 degree change that gives me a 30 fps swing. I don't think I have hunted elk in Wyoming when it's above freezing.
 
I use IMR 4831 in mild temps in my 6mm AI using Sierra Data. I also use 54.0 grains in my .280 with 139's at 3000 fps +- 25 fps with good results. Works good for engaging a bunch or rodents at mild mid-May temps with a 6mm AI, 87 Vmax & IMR 4831 but when it is real cold or hot I use VN 165 or some carefully rationed RL23. IMR is an olde extruded powder that fits good within its niche - temperature range & big grains require careful powder dispensing to get uniform velocities.

R-S Hunter is a good alternative to IMR 4831.
 
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