I am working up a load for my LR308, built off of a Fulton Armory receiver set and a Criterion 24in 1x10 barrel. Anyway, as charge and velocity increased, POI rose slightly and eventually started shifting right. Also, seemingly odd to me, the last three loads started shifting downward also. Is this horizontal shift anything unusual? My Savage .300WM just doesn't seem to care, piles them all in to one big ragged hole with little POI shift at all, vertical or horizontal.
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Ladder test and POI lateral shift?
- Thread starter Wheedle
- Start date
Seems normal in my experiences. How much rise did you see? How much shift to the right? How much down? What was the charge difference across the test? Got a picture of the target? I know that's a bunch of questions but it'd probably help you get an answer if you included such info.
Probably a 4 moa rise, with about the same to the right. I was shooting 168gn Speer Match HPBT, with IMR 4064 from 40.0 to 44.0 in .2gn increments. Velocity ranged from 2500 to 2786. Vertical max was at 42.6 and 2692. Horizontal shift started at 41.6 and 2600 and peaked at 43.4 and 2727. I have to say, though I saw no signs of overpressure or any cycling issues, I did not like the way the rifle shot at the hotter loadings above 2650fps. I have a good node from 40.4gn to 41.2gn that has a 8fps spread. These 5 rounds also had the closest grouping of any consecutive string of shots, barely a 1in total hole at 100 yds.
Basically you're saying water is wet. I would be amazed if the point of impact did not shift.
Barrel harmonics can cause a bullet to impact differently in any direction.
The fact that you are seeing a 4 moa shift bothers me. Is the barrel a very lite contour? Or there might be something else going on.
The fact that you are seeing a 4 moa shift bothers me. Is the barrel a very lite contour? Or there might be something else going on.
That makes me feel better. I was thinkin, 4 moa.........at 100? Whoa. Something ain't quite right for sure.
