Re: Rifle shoots better at longer range?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: CoryT</div><div class="ubbcode-body">It's fairly easy to prove out. Set your 800 yard target and get the rifle setup on it. Place a target of very thin paper, like tissue paper, at 100 yards on the trajectory line, you'll see your 800 yard target below the bottom edge of the 100 yard paper.
Shoot your 800 yard group. Your 100 yard group will never be angularly larger than the 800 yard group, in fact, it will normally be fractionally smaller.
The real problem is most people simply never see what the same group is like in both places. Unless you look at a lot of Doppler data, or have multiple acoustic targets, you just presume that the great groups you get at 800 would somehow have been a larger group at 100. Most shooter 'warm up' at 100 before they shoot further out, so they simply shoot better by the time they shoot the 800 yard group. Start cold and shoot three groups at 800, then three at 100 and report back. That's another simple test, though not as concrete as the dual groups. </div></div>
Although a very interesting test, this approach as you described it alone will not reveal the differential effects of parallax at short and long range, which are one likely cause of larger groups at short(er) distances than longer. As you pointed out, it will, however, show that the projectiles don't "stabilize" at longer distances and produce smaller groups.
If you could also get the targets set up so that you were actually using the 100 yd paper as the POA when firing for one set, yet still hit the 800 yd target, then you would be able effectively compare the group spreads at each distance fired using both both the shorter and longer POAs to see how parallax could cause larger groups at short range as compared to long range. Of course, that would presume that passing through the paper didn't affect the projectile POI at the longer range.
Another possibly simpler way to test the effect of parallax at short vs long range would be to set two targets up at 100 yd. For one target, use it as the POA when firing. For the other, set the scope/rifle up as if you were shooting at a much longer range and use another target or specific object as the POA. The 2nd target at 100 yd would still have to be set up so that it was the POI when using the longer range POA. If parallax was the culprit, this test should reflect that. Anyhow, very interesting test, thanks for posting it.