I was at the range today checking some new loads for a .44 spl and noticed for about the 500th time in my life that the point of impact moves in the strangest ways as loads change. Going up in charge makes the group rise at 25 yds and drop at 7. Changing from LSWC to LRN of the same weight moves the point up and to the left. Does anyone have a good predictive sense of how load changes effect the point of impact? Frankly I'm pretty sure each of my guns acts a little differently. I am shooting offhand only (no rest) and my groups aren't bad. From shooting session to shooting session the same load seems to hit pretty close to the same place.
Effect of load on point of impact
1 - 3 of 3 Posts
Joined
·
38,513 Posts
Fred,
Many times I have fiddled with the powder charge (read velocity) of a load to move the point of impact. The reason is generally to try and make the point of impact with a target load match a hunting load, at a certain range.
Usually, as you slow the bullet down (less powder), I find that the point of impact rises a little at .25 yards.
Your grip has a lot to do with it. Try a few rounds with the gun held fairly relaxed, then a few with a really tight grip. Chances are that you will see a difference at the 25 yard range.
Also, generally, the light bullets will impact lower at short ranges than the heavier bullets, if the velocities are similar.
This is all 'general' observations and I'm sure that some people will report different results. The shorter the barrel on the gun, the less difference I find that it makes.
Many times I have fiddled with the powder charge (read velocity) of a load to move the point of impact. The reason is generally to try and make the point of impact with a target load match a hunting load, at a certain range.
Usually, as you slow the bullet down (less powder), I find that the point of impact rises a little at .25 yards.
Your grip has a lot to do with it. Try a few rounds with the gun held fairly relaxed, then a few with a really tight grip. Chances are that you will see a difference at the 25 yard range.
Also, generally, the light bullets will impact lower at short ranges than the heavier bullets, if the velocities are similar.
This is all 'general' observations and I'm sure that some people will report different results. The shorter the barrel on the gun, the less difference I find that it makes.
Revolvers are laws unto themselves
I have three 45 Colt double action revolvers, two S&Ws and one Colt, all three shoot 255 grain Saeco wheel weight bullets using rooster Red or LBT, with 8.5 or 9 grains of Unique.
With that said I keep a little note book in the gun case with notes relating to that revolver. The Smith I've used the longest, a mod 25 4 inch, likes to have a firm grip with the thumb pressed into the frame above the cyclinder latch. The second Smith is a mod 625 four inch lugged barrel, cut your thumb off, put your thumb any place except on the frame above the cyclinder latch and do a death grip on the frame. The Colt Anaconda 6 inch is fairly easy going with the above load, just get a good grip and it will put the bullets were I aim. When I switch to the 300 grain bullet with 20 grains of H110, the handgun wants a tight grip and the thumb on the frame near the hammer.
I keep the note pads to remind myself, so I don't spend a lot of time reinventing the wheel each shooting sesion.
Jim
I have three 45 Colt double action revolvers, two S&Ws and one Colt, all three shoot 255 grain Saeco wheel weight bullets using rooster Red or LBT, with 8.5 or 9 grains of Unique.
With that said I keep a little note book in the gun case with notes relating to that revolver. The Smith I've used the longest, a mod 25 4 inch, likes to have a firm grip with the thumb pressed into the frame above the cyclinder latch. The second Smith is a mod 625 four inch lugged barrel, cut your thumb off, put your thumb any place except on the frame above the cyclinder latch and do a death grip on the frame. The Colt Anaconda 6 inch is fairly easy going with the above load, just get a good grip and it will put the bullets were I aim. When I switch to the 300 grain bullet with 20 grains of H110, the handgun wants a tight grip and the thumb on the frame near the hammer.
I keep the note pads to remind myself, so I don't spend a lot of time reinventing the wheel each shooting sesion.
Jim
1 - 3 of 3 Posts
