Doing some load testing with the 30BR. Using BIB 118 10 ogive bullets,Tungsten coated), over H4198 and Fed 205 primers.
Loaded up 5 rounds each 32.4, 32.8, 33.2,33.6,34.0,34.2,34.4,34.6,and 34.8 gr. Loaded 100 rounds total, 50 0.030" off the lands, 50 0.015" into the lands.
Shot everything @ 200 yards, pretty calm conditions, but a wisp of a breeze occasionally. The 0.015" jambed bullets shot all over the place, I was getting pretty disgusted at that point. The I shot the 0.030" off batch- -wow, what a difference. This is how they should shoot! a lot of cutting the same hole stuff, with a few fliers.,I ain't the best shot, lots of learning to do)
I did find 2 loads that were outstanding, compared to the rest: 32.8gr, and 34.4gr. I'm assuming these are the "high" and "low" nodes. The loads on either side of both of these were acceptable, these loads were noticeably better. Notice that there is a .4 grain step around the 32.8, but only a .2 gr difference around the 34.4 load.
My question for discussion - should I load for the high node, or the low node?
What band do you usually find more forgiving in different temperature conditions?
Is there any other variable I should try? Deeper? Closer? When you're 0.030" off, how far do you need to change it to be significant?
Strange thing on the jambed loads vs the 0.030" off loads. The recoil from the jambed loads was "sharper". don't know how to describe it, but the gun seemed to come back into my shoulder faster. I don't have a chrono, so I have no idea of velocity.
Loaded up 5 rounds each 32.4, 32.8, 33.2,33.6,34.0,34.2,34.4,34.6,and 34.8 gr. Loaded 100 rounds total, 50 0.030" off the lands, 50 0.015" into the lands.
Shot everything @ 200 yards, pretty calm conditions, but a wisp of a breeze occasionally. The 0.015" jambed bullets shot all over the place, I was getting pretty disgusted at that point. The I shot the 0.030" off batch- -wow, what a difference. This is how they should shoot! a lot of cutting the same hole stuff, with a few fliers.,I ain't the best shot, lots of learning to do)
I did find 2 loads that were outstanding, compared to the rest: 32.8gr, and 34.4gr. I'm assuming these are the "high" and "low" nodes. The loads on either side of both of these were acceptable, these loads were noticeably better. Notice that there is a .4 grain step around the 32.8, but only a .2 gr difference around the 34.4 load.
My question for discussion - should I load for the high node, or the low node?
What band do you usually find more forgiving in different temperature conditions?
Is there any other variable I should try? Deeper? Closer? When you're 0.030" off, how far do you need to change it to be significant?
Strange thing on the jambed loads vs the 0.030" off loads. The recoil from the jambed loads was "sharper". don't know how to describe it, but the gun seemed to come back into my shoulder faster. I don't have a chrono, so I have no idea of velocity.