I want to share the results of an experiment I did today. I have two Remington Model 700 rifles in.270 caliber and I decided to see if neck sizing would provide any advantage in accuracy over standard full length resizing. In addition I looked for any difference between using standard vs magnum primers.
Recognizing there is no universal acceptance of a 3-shot group to prove anything, I used that because I don’t ever expect to shoot even that many at one time at a deer. All loads had the primer pockets cleaned.
Each rifle prefers a different bullet. Rifle #1 is 31 years old and has a 22-inch barrel; it prefers Hornady 150gr spires with 56.0 gr of H-4831. Rifle #2 is 20 years old, has a 24 inch barrel and prefers Hornady 140gr SST with 56.0 gr of H-4831. These loads had been previously developed and are accurate enough for hunting.
Rifle #1had:
1) R-P cases full-length resized, measured varied lengths but all close to maximum of 2.540 inches and charged with CCI Large Rifle Magnum primers. The 3 shot group was 1.098 inches with shots landing 1.25” to 1.50” above the point of aim.
2) R-P cases neck sized and trimmed to minimum length of 2.530 inches, charged with CCI magnum primers The 3-shot group was 1.973,” with shots landing 0.75 to 2.25 inches above the aim point.
3) R-P cases neck sized, trimmed to minimum 2.530 inches but charged with CCI large rifle primers (not magnum). The 3-shot group was 0.723 inches, with all 3 shots landing 1.50 inches directly above the point of aim, with 2 holes touching.
Now I need to repeat this load but with cases that range between 2.530-2.540 inches in length, neck resized. But clearly this load should not use magnum primers.
Rifle #2 had:
The same charge of H-4831, large rifle primers (not magnum), all cases varied between 2.530 and 2.540 inches. The only difference was neck resize vs full length resize.
4) Neck sized: the first shot out of a clean barrel went 5 inches high, directly above the point of aim. The next 3 shots grouped 0.723 inches, above and slightly to the left, 2.5 inches high.
5) Full length resized: 3 shots grouped 1.098 inches with 2 touching and breaking paper between them, landing in the same spot – slightly left, 2.5 inches high.
What did I learn? Both of these rifles are more accurate with neck sized cases and non-magnum primers. It remains to be seen if varied case length matters in Rifle #1.
For those handloaders who are early in your hobby, this is an example of how much fun it can be!
Recognizing there is no universal acceptance of a 3-shot group to prove anything, I used that because I don’t ever expect to shoot even that many at one time at a deer. All loads had the primer pockets cleaned.
Each rifle prefers a different bullet. Rifle #1 is 31 years old and has a 22-inch barrel; it prefers Hornady 150gr spires with 56.0 gr of H-4831. Rifle #2 is 20 years old, has a 24 inch barrel and prefers Hornady 140gr SST with 56.0 gr of H-4831. These loads had been previously developed and are accurate enough for hunting.
Rifle #1had:
1) R-P cases full-length resized, measured varied lengths but all close to maximum of 2.540 inches and charged with CCI Large Rifle Magnum primers. The 3 shot group was 1.098 inches with shots landing 1.25” to 1.50” above the point of aim.
2) R-P cases neck sized and trimmed to minimum length of 2.530 inches, charged with CCI magnum primers The 3-shot group was 1.973,” with shots landing 0.75 to 2.25 inches above the aim point.
3) R-P cases neck sized, trimmed to minimum 2.530 inches but charged with CCI large rifle primers (not magnum). The 3-shot group was 0.723 inches, with all 3 shots landing 1.50 inches directly above the point of aim, with 2 holes touching.
Now I need to repeat this load but with cases that range between 2.530-2.540 inches in length, neck resized. But clearly this load should not use magnum primers.
Rifle #2 had:
The same charge of H-4831, large rifle primers (not magnum), all cases varied between 2.530 and 2.540 inches. The only difference was neck resize vs full length resize.
4) Neck sized: the first shot out of a clean barrel went 5 inches high, directly above the point of aim. The next 3 shots grouped 0.723 inches, above and slightly to the left, 2.5 inches high.
5) Full length resized: 3 shots grouped 1.098 inches with 2 touching and breaking paper between them, landing in the same spot – slightly left, 2.5 inches high.
What did I learn? Both of these rifles are more accurate with neck sized cases and non-magnum primers. It remains to be seen if varied case length matters in Rifle #1.
For those handloaders who are early in your hobby, this is an example of how much fun it can be!