Saturday, January 16, 2010

First of the year range report

Sorry to post all of these range reports at the same time...

This is a three shot string at 100 yards of .243 Winchester out of a Remington 700 with a short stock (for me, it belonged to someone shorter than me). The drop is 1.7 inches between the centers of the top and bottom shot. We used a bench rest, but heart/muscle twitches (all before you even pull the trigger) were probably moving it about .25-.5 MOA (more for the breathing ~2 MOA?). The horizontal spread is .22 inches, which I find reasonable at 100 yards ;-). So, about the vertical spread, are we going to call it velocity differences in the rounds? (I did some simple calcs, probably not) Barrel harmonics? My own tendency to have a 7x spread between horizontal and vertical? Maybe the barrel heating up? (it was about 34 degrees?)

I wanted to see my performance on the Marlin 795 standing at 25 yards, so I did an 11 shot string. Spread was 1.2 inches horizontally and 3.25 vertically. This was with the Thunderbolt ammo, which I previously did a .85 inch spread horizontally while sitting at 25 yards. My vertical performance was ~3x my horizontal performance. I am going to try and think about that when I shoot to see if I can correct it as it happened with two different guns and two different ammos that day that I was much worse in the vertical direction, whether standing or using a bench rest.

We also shot at balloons, at the end I shot a 5 shot string of .22 lr at 4 balloons at 100yards (maybe 6-8 inches wide?), I hit the first two with the first two shots then messed up the rest. I hadn't run any .22 lr ballistics, so I didn't know what the drop was going to be, I estimated I was holding over 3-4 inches, upon calculating it using a 50 yard zero it should have hit -6.5 inches, which would have hit the balloon.

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