I am in the process of working up a 308 load for Elk season this year, and I did some load development with the 165 Sierra Tipped Game King in virgin Nosler brass with Federal Gold Medal Match primers and two different powders. The powder selections is where I saw some interesting stuff, and I have also concluded, conclusively even, that low SD's do NOT equal tight groups.
I started off with Shooters World Precision Rifle powder. Varget is as rare as Pixie dust right now, and I was able to get 3 lbs of this stuff to try out for $20/lb. It meters really well and overall, I was quite pleased with the results. The only thing left is to get more data on the temperature stability and to true my ballistics chart at distance (though I wont be taking a shot past 450 yards, its still good info to have should a wolf walk into view at distance).
I also used IMR 4166, because its an Enduron powder and should be quite temp stable as a result. I did find however that 4166 is a long stick powder and as a result does not meter very well at all, and it seemed to give me erratic downrange results on paper at even 100 yards.
I've heard of "powder incompatibility", but I didn't quite believe it.. Maybe I do now? What are your thoughts? Going from groups of 1" or less with the Shooters World, to a 3.5+" group with the first group of IMR 4166 makes me a bit of a believer, even if the 4166 never did seem to settle in over the 15 rounds fired..
4166 did however give a 100+ FPS advantage over Shooters World, though I would much rather have accuracy over velocity.
Can anyone lend any insights on the erratic behavior of the 4166 groups? See the targets below.
P.S. If anyone is interested, I have settled in on the 45.2 grains of Shooters World as my hunting load. All that is left to do is play with seating depth to see if I can tighten the groups up better than the .83" I saw with the 45.1gr load and shoot at distance to true up the drop chart.
I started off with Shooters World Precision Rifle powder. Varget is as rare as Pixie dust right now, and I was able to get 3 lbs of this stuff to try out for $20/lb. It meters really well and overall, I was quite pleased with the results. The only thing left is to get more data on the temperature stability and to true my ballistics chart at distance (though I wont be taking a shot past 450 yards, its still good info to have should a wolf walk into view at distance).
I also used IMR 4166, because its an Enduron powder and should be quite temp stable as a result. I did find however that 4166 is a long stick powder and as a result does not meter very well at all, and it seemed to give me erratic downrange results on paper at even 100 yards.
I've heard of "powder incompatibility", but I didn't quite believe it.. Maybe I do now? What are your thoughts? Going from groups of 1" or less with the Shooters World, to a 3.5+" group with the first group of IMR 4166 makes me a bit of a believer, even if the 4166 never did seem to settle in over the 15 rounds fired..
4166 did however give a 100+ FPS advantage over Shooters World, though I would much rather have accuracy over velocity.
Can anyone lend any insights on the erratic behavior of the 4166 groups? See the targets below.
P.S. If anyone is interested, I have settled in on the 45.2 grains of Shooters World as my hunting load. All that is left to do is play with seating depth to see if I can tighten the groups up better than the .83" I saw with the 45.1gr load and shoot at distance to true up the drop chart.
