Home Forums Hunting & Shooting Ask The Gunwriters Bullets Different Point of Impact

The rifle starts to recoil as the bullet starts to move, and so POI is affected by, among other things, how much recoil and how much time between the bullet starting to move and it leaving the muzzle. Just to complicate things, the rifle doesn't recoil straight back, but tends to pivot up at the muzzle (because the recoil is transferred via the butt, below the line of the bore on most rifles). It can also pivot laterally due to things like cast and the effect of the shooter's cheek and other aspects of how the rifle's held. In fact it is for this reason that you can get different POI from different shooting positions, even without changing loads.

As well, with all of this movement the barrel is not infinitely stiff, and it tends to flex as all of this is going on, and this in turn can be affected by contact with the fore-end.

All of these things can contribute to different POI, including lateral shift.

Usually all of this doesn't matter all that much: you zero for the load you'll use, and (if you're smart) from the position you'll favour for the longer shots, and leave it at that. It only really starts to show up if you are shooting different loads, positional matches, or trying to regulate a double rifle.

All of the above or none of the above. You just have to shoot them to find out.

Had a similar experience but then saw I had one 4 shot group and one 6 shot group, wasn't an equipment problem.

I feel lucky if different weight bullets DO impact close together. I have a 35 Whelen that puts 225 Accubonds about 1/2” higher that the 200 Accubond that’s a bit higher velocity. That puts them pretty close together down range.

What powder(s) are you using?

One thing I've found during my experiments at very different temperatures is that POI can vary considerably with temp-sensitive powders.

An example from 20+ years ago was working up two loads for my .338 Winchester Magnum, one with 200-grain bullets and RL-15, and another with 250s and H4831 Extreme. They shot close to the same place at 70 degrees Fahrenheit, but not at 90 degrees in Africa--or at around zero F. in Montana.

I have an extremely accurate, custom, heavy-barrel AR in .223. It shoots bugholes with 60 grain Sierra HP’s over Varget. It also shoots bugholes with 65 grain SGK’s over Varget. The 65 grain bugholes are 3/4” from the 60 grain bugholes at 2 o’clock.