That is a very enlightening article, thanks for posting it stagpanther.
Here's the meat and potatoes of it.
I recently received the little .260 Remington, and while I could not get factory loads to shoot under 1½ inches, I had no problem finding a handload using Sierra 120-grain bullets that shot under one inch. I did not measure the velocity, but I am sure it was nothing to write home about. No matter … I wanted to see what effect canting would have, and a rifle with a high trajectory at 400 yards would definitely show any ill effects.
I went out to my local shooting range and zeroed the rifle at 400 yards when ScopLevel #1 read level. I shot several groups to be sure of the zero. Next, I rotated the rifle until ScopLevel #2 read level. This produced a cant of 5°. I shot several groups at 400 yards with the canted rifle, and measured the effects.
The results? Surprising, to say the least. When canted, the bullets struck about 4 inches to one side. I expected some horizontal movement. But I did not expect the vertical movement to be as large as it was — the vertical impact averaged 3.75 inches low!
The .260 Remington is a cute little cartridge, but it is certainly no barnburner. I took out one of my 7mm Remington Magnums. This is one of the guns I shoot religiously every week at long range. I usually go to the range, place a target, and then try to guess how the environmental conditions will affect my bullet (I use a laser rangefinder, so the range is not a problem). On that particular day when I shot without any canting, my bullets hit 2 inches to the left and 3.5 inches high at 700 yards. I then shot with the rifle canted 5°. The results were astounding.
The bullets hit 6 inches to the right of the uncanted shots, but 8 inches low. The next week I broke out my .220 Swift, which at 700 yards has a trajectory similar to the 7mm. Its bullets hit 7 inches low when canted 5°. Both groups were under ½ moa. Further shooting confirmed my initial results.
All three rifles hit much lower than trigonometry calculations would have predicted. I cannot figure out why. The horizontal displacement was just about what I expected (my shooting was done in early morning under calm conditions), but the vertical displacement is difficult to explain. Certainly my shooting results are not statistically valid, but they were ther nonetheless.
Here's the meat and potatoes of it.
I recently received the little .260 Remington, and while I could not get factory loads to shoot under 1½ inches, I had no problem finding a handload using Sierra 120-grain bullets that shot under one inch. I did not measure the velocity, but I am sure it was nothing to write home about. No matter … I wanted to see what effect canting would have, and a rifle with a high trajectory at 400 yards would definitely show any ill effects.
I went out to my local shooting range and zeroed the rifle at 400 yards when ScopLevel #1 read level. I shot several groups to be sure of the zero. Next, I rotated the rifle until ScopLevel #2 read level. This produced a cant of 5°. I shot several groups at 400 yards with the canted rifle, and measured the effects.
The results? Surprising, to say the least. When canted, the bullets struck about 4 inches to one side. I expected some horizontal movement. But I did not expect the vertical movement to be as large as it was — the vertical impact averaged 3.75 inches low!
The .260 Remington is a cute little cartridge, but it is certainly no barnburner. I took out one of my 7mm Remington Magnums. This is one of the guns I shoot religiously every week at long range. I usually go to the range, place a target, and then try to guess how the environmental conditions will affect my bullet (I use a laser rangefinder, so the range is not a problem). On that particular day when I shot without any canting, my bullets hit 2 inches to the left and 3.5 inches high at 700 yards. I then shot with the rifle canted 5°. The results were astounding.
The bullets hit 6 inches to the right of the uncanted shots, but 8 inches low. The next week I broke out my .220 Swift, which at 700 yards has a trajectory similar to the 7mm. Its bullets hit 7 inches low when canted 5°. Both groups were under ½ moa. Further shooting confirmed my initial results.
All three rifles hit much lower than trigonometry calculations would have predicted. I cannot figure out why. The horizontal displacement was just about what I expected (my shooting was done in early morning under calm conditions), but the vertical displacement is difficult to explain. Certainly my shooting results are not statistically valid, but they were ther nonetheless.
Last edited: