versifier
08-21-2006, 11:08 PM
I have been tinkering with the Lee 309-180-R in my .308 and have some results to post. I used my Rem 788, a rifle that will keep jacketed bullets in 1/2MOA as long as I let the barrel cool off properly. It's bore is .309.
First, I was playing with alloys and three powders, IMR3031, Unique, and RE-7. Alloys were Lino, H2O dropped Lino, 1/2 Lino & 1/2 pure, (all weighed 160-164gr) OAL 2.560, sized .308 and lubed with LA. Ten different charge weights and 50 yd, 5rd groups to find the best charge weights gave me:
3031 30gr 2", 31gr 1.5"
Unique 11gr 1.75"
RE-7 22gr 2", 23gr 1"
I then retested with ten shot groups to see if the first results were repeatable, and they were - groups opened up between .5"- 1.5".
Today I took the Unique charge and the same boolit in ww sized to .310 in three different brands of cases just to see what would happen. (I'm going to work up the same test as I did with the lino boolits and all three powders, but I got curious and decided to see what would happen if I skipped a step in the testing.)
The first groups I used the same .309 sized boolits in RP cases (I had used Winchester in the first test) and got a 3" 10shot group. Not impressed, but it tracked with results from the first test.
Then I switched to .310 boolits cast of ww (weight 182gr):
RP cases: 3 3/8"
Win cases: 2 3/4"
Fed cases: 2 1/2"
It won't prove anything yet, until I repeat the original incremental powder tests with the larger diameter ww boolits, but I found it interesting that the larger softer boolits appear to be not as accurate as the smaller harder ones. I was expecting to see the groups shrink noticeably, but they did not. Back to the logical testing routine to find out why. Sometimes you luck out when you skip a step, sometimes you don't, but either way you learn something.
First, I was playing with alloys and three powders, IMR3031, Unique, and RE-7. Alloys were Lino, H2O dropped Lino, 1/2 Lino & 1/2 pure, (all weighed 160-164gr) OAL 2.560, sized .308 and lubed with LA. Ten different charge weights and 50 yd, 5rd groups to find the best charge weights gave me:
3031 30gr 2", 31gr 1.5"
Unique 11gr 1.75"
RE-7 22gr 2", 23gr 1"
I then retested with ten shot groups to see if the first results were repeatable, and they were - groups opened up between .5"- 1.5".
Today I took the Unique charge and the same boolit in ww sized to .310 in three different brands of cases just to see what would happen. (I'm going to work up the same test as I did with the lino boolits and all three powders, but I got curious and decided to see what would happen if I skipped a step in the testing.)
The first groups I used the same .309 sized boolits in RP cases (I had used Winchester in the first test) and got a 3" 10shot group. Not impressed, but it tracked with results from the first test.
Then I switched to .310 boolits cast of ww (weight 182gr):
RP cases: 3 3/8"
Win cases: 2 3/4"
Fed cases: 2 1/2"
It won't prove anything yet, until I repeat the original incremental powder tests with the larger diameter ww boolits, but I found it interesting that the larger softer boolits appear to be not as accurate as the smaller harder ones. I was expecting to see the groups shrink noticeably, but they did not. Back to the logical testing routine to find out why. Sometimes you luck out when you skip a step, sometimes you don't, but either way you learn something.