- Banned
- #1
So I'm testing some loads for my 270 and my 300 WM and I'm having trouble getting consistent velocities...hoping someone can give me some tips on what to check.
I feel like I'm being VERY meticulous about my process: tracking number of times fired for brass and always using the same batch for each test, cleaning, prepping, and measuring cases before loading, measuring powder with my beam scale and checking on a (cheap) digital scale, seating all bullets to a consistent CBTO (within 1 thousandth) and yet I get this inconsistency.
Example: Last night I took the 270 to the range with my chrono. I had four 3-shot groups to test different CBTO. On every group I would have two shots that grouped almost touching with a velocity difference of less than 20 FPS, but I would have one shot in the group that would be (on average) about 1 inch away from the other two, and the velocity on this "flier" would be off by almost 100 FPS (2 shots at appr. 2650 FPS grouping together, one shot at 2550 FPS about an inch away). That said, I'm still at around 1 MOA for the total group so it might be acceptable I've just seen that most people who hand load are able to get velocities within 10% and I'm not getting that every time.
I'm getting the same thing on my 300 WM for which I use a different powder and bullet obviously. I am using the same primers on both rounds (winchester WLRM's) so I'm going to do a test this weekend with some different primers, but other than that the only common factor is me and something I'm doing wrong. If anyone has any advice or other things I can check I would really appreciate it!
I feel like I'm being VERY meticulous about my process: tracking number of times fired for brass and always using the same batch for each test, cleaning, prepping, and measuring cases before loading, measuring powder with my beam scale and checking on a (cheap) digital scale, seating all bullets to a consistent CBTO (within 1 thousandth) and yet I get this inconsistency.
Example: Last night I took the 270 to the range with my chrono. I had four 3-shot groups to test different CBTO. On every group I would have two shots that grouped almost touching with a velocity difference of less than 20 FPS, but I would have one shot in the group that would be (on average) about 1 inch away from the other two, and the velocity on this "flier" would be off by almost 100 FPS (2 shots at appr. 2650 FPS grouping together, one shot at 2550 FPS about an inch away). That said, I'm still at around 1 MOA for the total group so it might be acceptable I've just seen that most people who hand load are able to get velocities within 10% and I'm not getting that every time.
I'm getting the same thing on my 300 WM for which I use a different powder and bullet obviously. I am using the same primers on both rounds (winchester WLRM's) so I'm going to do a test this weekend with some different primers, but other than that the only common factor is me and something I'm doing wrong. If anyone has any advice or other things I can check I would really appreciate it!