Temperature stable powder for 338 Lapua

[fatrack]

Heres an example out of my log book.

300 SMK
99 grains US869
Federal match 210 primer
Chronies 2810 fps @ 25C

Gun and ammo temp in the truck are 23C. Outside temp is -2C. Set up my shooting mat and dial 9.25 MOA for a 556 yard shot and make a hit. Ten minutes later fire another round and hit 1 MOA low. Add 1 MOA of up and hit. Ten minutes later fire another round that is 3/4 MOA low. Adjust and hit. This experience is what convinced me to switch powders.

 

[datatools]

Heres an example out of my log book.

300 SMK
99 grains US869
Federal match 210 primer
Chronies 2810 fps @ 25C

Gun and ammo temp in the truck are 23C. Outside temp is -2C. Set up my shooting mat and dial 9.25 MOA for a 556 yard shot and make a hit. Ten minutes later fire another round and hit 1 MOA low. Add 1 MOA of up and hit. Ten minutes later fire another round that is 3/4 MOA low. Adjust and hit. This experience is what convinced me to switch powders.

I have experienced the same scenario with the IMR4350. Everything works fine as long as I keep the ammo at a consistent temperature. I can let the rifle freeze without any difference in POI, but if I let the ammo get down to minus 20 there is a big difference.

 

[CanuckWR]

I have a 338LM load with retumbo and 300gr smk's. Worked well at -15c at 2690fps and one day I expect it will warm up enough to try in warmer temps. One day it will warm up...

 

[bradtothebone]

Us 869??!!

Kevan, I too was using 869, I have no issues with it for my summer/spring/fall shooting applications, but when I use it in the winter not only do I need more elevation it shoots sporatically. One winter i went out at -20 and had to increase my load charge by 4+ grains to get it back grouping...


I have changed to H1000 and find it suits my needs better, although I do believe US 869 performs slightly better in the summer for accuracy and velocity.

Brad