Originally Posted by Engineering101
I was at the range a few days ago to break in a brand new Kimber Montana in 280 AI. We did no formal barrel break in but fired 24 rounds in 8 different loads of 3 each. It pretty much shot everything into 1 inch 3-shot groups at 100 yards. This was using the 145 grain Barnes LRX with H4831SC. Since there wasn't much difference between the groups we decided to go with the max load we tested of 60.5 grains. Primers looked good, no pressure signs so there is probably a bit more room on the upside. If you check the Nosler handbook (it is available on line) you will notice that max loads of IMR7828 are compressed so the SSC version is the way to go. It looks like you would get up to 100 fps more velocity with IMR7828SSC but temperature stability may not be as good as the H4831SC. Try them both and see what happens (forget the Varget).
Varget is definitely too fast for a 140gr bullet in that case. If you were shooting 120's, then I'd say go for the Varget.
7828 SSC has been very temp stable for me. Then again, I'm the odd-duck that has had the worst luck with Alliant powders and H1000 NOT being temp stable. Could have been bad batches, but when you get 30 degree temp swings and H1000 loads from the same exact batch you loaded in the winter, that were cloverleaf loads, and they magically turn into 4" loads during the spring....Something ain't right.
I'm not sure if it's temp stable, but I hear Reloder 17 also gets incredible velocities with the '06 based cartridges.
"I'm just a peckerwood who lives in the hills with too many guns..." - Bob Lee Swagger
"Give me a minute...I'm good. Give me an hour...I'm great. Give me 6 months...And I'm unbeatable." - Col. Hannibal Smith
Originally Posted by WildRose
The 284 is to the STW what a tricycle is to a Ninja.