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OCW, Ladder? My suggestion is to start with velocity... AND the best barrel you can buy.
1. For starters, determine, though research and asking questions, a known accuracy node for the cartridge and bullet you're using. Then work up velocity info with chrono.
2. I feel with a really good barrel, shooting 3-shot groups, you can have a very good load with under 40 rounds expended. For the smaller cartridges, try 0.2 grain increments. Suggest, for bench bolt guns, you try .006-7 into the lands vs. .020 out for starters. Confirm with a couple 5-shot groups. Into the lands means .006-7 past "first touch" as explained below.
3. Guys who are spending 150 rounds + with OCW are really going overboard. I see guys doing OCW in pursuit of some magic load, when they are really just struggling with a mediocre factory barrel (and/or a crappy rest set-up). See this article today:
http://bulletin.accurateshooter.com/2019/04/dont-waste-time-and-ammo-on-a-poor-factory-barrel/
4. Another comment. When you have a really good barrel, it probably is not fussy. My best 6BR barrel shot four different bullets, with four different powders, all into quarter-inch or less. Bullets: 80gr Berger, 95gr Berger, 90gr Scenar, 105gr Scenar. Powders: Varget, Norma 203B (RL15), IMR 8208, H4895.
Regarding "into the lands". We find that many shooters don't measure this correctly at all. They push the OAL tool's plastic shaft too aggressively. You want to find "first touch". If you use the tool correctly, this should be repeatable 4 of 5 times within .001-.002. If you are not getting a repeatable measurement of first contact you are using the tool incorrectly (typically pushing too hard).
Note, with a new barrel, that "first touch" point can move .010" or more after 40+ rounds, but then should stabilize.
1. For starters, determine, though research and asking questions, a known accuracy node for the cartridge and bullet you're using. Then work up velocity info with chrono.
2. I feel with a really good barrel, shooting 3-shot groups, you can have a very good load with under 40 rounds expended. For the smaller cartridges, try 0.2 grain increments. Suggest, for bench bolt guns, you try .006-7 into the lands vs. .020 out for starters. Confirm with a couple 5-shot groups. Into the lands means .006-7 past "first touch" as explained below.
3. Guys who are spending 150 rounds + with OCW are really going overboard. I see guys doing OCW in pursuit of some magic load, when they are really just struggling with a mediocre factory barrel (and/or a crappy rest set-up). See this article today:
http://bulletin.accurateshooter.com/2019/04/dont-waste-time-and-ammo-on-a-poor-factory-barrel/
4. Another comment. When you have a really good barrel, it probably is not fussy. My best 6BR barrel shot four different bullets, with four different powders, all into quarter-inch or less. Bullets: 80gr Berger, 95gr Berger, 90gr Scenar, 105gr Scenar. Powders: Varget, Norma 203B (RL15), IMR 8208, H4895.
Regarding "into the lands". We find that many shooters don't measure this correctly at all. They push the OAL tool's plastic shaft too aggressively. You want to find "first touch". If you use the tool correctly, this should be repeatable 4 of 5 times within .001-.002. If you are not getting a repeatable measurement of first contact you are using the tool incorrectly (typically pushing too hard).
Note, with a new barrel, that "first touch" point can move .010" or more after 40+ rounds, but then should stabilize.
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