Originally Posted by
Ridge Runner
afp,
I don't do much group shooting other than 300 yard load developement with my LR rigs, My main goal is to put the first round cold bore shot in a deers vitals at whatever range he happens to show up at.
So I mostly bust rocks and steel out to 1100 yards alternating range and targets every shot. however here is a fireform group from my 7mm AM, 100 yards, this is a cartridge that has 122 gr capacity of H2o
also here is a target I shot while checking the consistancy of my scope, 2 shots at 660 yards, I dialed up from a 100 yard zero, fired a shot, went back to 100 yard zero and dialed up again and fired the other, it was running .25 MOA high, so the next session I changed the BC of the 160 accubond in my exbal program from .531 to .62 and have taken 17 deer with 19 shots from 500 yards to over 3/4's of a mile since.
I know what BR rifles do, I only shoot off a bipod with a rear support, I can tell you, this rifle shoots better than I do.
RR
Please don't think that I am disparaging the kind of shooting you are doing. It is a different game than LR BR. The fact that you have settled on a 160 Accubond helps make my point that ultra high BC isn't the most important factor in making long range hits.....and that is my main point here. That and I know you know that just as my 1K BR rifle would be a poor choice for long range hunting; your LR deer rifle wouldn't do so well at 1K BR. This makes sense, as they were built with completely different purposes in mind.
My rifle needed to be able to consistent shoot 5-shot groups of around 1/2 MOA at 1000 yds regardless of how hot the barrel was. My rig required 28 MOA to be centered at 1000 yds. Your rifle needs the ability to quickly center at random ranges and hit within a 1 MOA circle. It also needs to be somewhat portable. Swap roles with either rig and they will be at the bottom of the pack.
When I was competing, we'd always fire at a 12" square piece of tractor blade that was painted green. We called in our "gong" it was set up on a dirt bank at 975 yds for the sole purpose of making sure guys were close enough to be on paper before we started the sighter period. If we didn't do that, guys with new rigs/loads could take a long time to even find paper.
Anyway, that first shot for me was always from a clean, cold barrel, with the scope settings I had dialed in from the previous match. That first hit was usually very close to the gong, close enough to take a deer, and that always suprised me given the windy conditions we shot in.
I wound up doing my load devlopment at 100 yds through an Oehler 35 Chrono. The load that shot 3.5" at 1000 yds never shot better than 1/2" at 100, but it was a nice round, 5-shot group with extreme spreads of 11 fps with both new and fireformed brass. We always looked for round groups at .5 to .6" with low extreme spreads and would pick a load that printed a little larger group if it had a better ES. 20 FPS of ES equals 2.5" of vertical dispersion at 1000 yds.