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Bogie · February 1, 2001, 03:52 PM

We need this stuff in a FAQ...

The "benchrest" way:

Buy a buncha powder that you know is a proven performer in your calibre (i.e., H380 in a .22-250, H322 in the 6PPC, IMR4198 in the .22PPC, IMR4895 in the .308, etc.).

Prep a few rounds of brass. Load a bunch up for starters with your "starting" load. These are foulers.

Put a bunch of wind flags between you and a target that is preferably at least 200 yards away. Use a solid bench. If you don't have a front rest and rear bag, improvise something. DO NOT put the rifle on something solid. Don't even bother trying it you've got a lot of headwind or tailwind.

Now, clean the rifle, fire two-three foulers, and start firing three shot groups, starting at the minimum charge, and working up about 3/10 grain at a time. Load the bullets to just touch the lands or to max OAL. Fire only when the flags show a consistent condition. Your rifle's groups should progressively show vertical, closing up to the optimum groups. Don't fire more than 20 shots a time without cleaning. When the groups tighten up, you've got a sweet spot with that load. After they tighten, if you keep adding powder, they'll open up, and may or may not tighten again before you run out of pressure leeway.

The chronograph doesn't matter - Only your vertical. Horizontal is generally operator error in disregarding what the flags say.

When you think you've found a sweet spot, double check with a couple of five-shot groups.

February 1, 2001, 03:52 PM	#8
Bogie Senior Member Join Date: June 5, 2000 Location: Job hunting on the road... Posts: 3,827	We need this stuff in a FAQ... The "benchrest" way: Buy a buncha powder that you know is a proven performer in your calibre (i.e., H380 in a .22-250, H322 in the 6PPC, IMR4198 in the .22PPC, IMR4895 in the .308, etc.). Prep a few rounds of brass. Load a bunch up for starters with your "starting" load. These are foulers. Put a bunch of wind flags between you and a target that is preferably at least 200 yards away. Use a solid bench. If you don't have a front rest and rear bag, improvise something. DO NOT put the rifle on something solid. Don't even bother trying it you've got a lot of headwind or tailwind. Now, clean the rifle, fire two-three foulers, and start firing three shot groups, starting at the minimum charge, and working up about 3/10 grain at a time. Load the bullets to just touch the lands or to max OAL. Fire only when the flags show a consistent condition. Your rifle's groups should progressively show vertical, closing up to the optimum groups. Don't fire more than 20 shots a time without cleaning. When the groups tighten up, you've got a sweet spot with that load. After they tighten, if you keep adding powder, they'll open up, and may or may not tighten again before you run out of pressure leeway. The chronograph doesn't matter - Only your vertical. Horizontal is generally operator error in disregarding what the flags say. When you think you've found a sweet spot, double check with a couple of five-shot groups.