When to say when?
- Thread starter MakBaba
- Start date
denton
Member
The OP's question is a good one: Work up to what?
Working up to pressure signs is ineffective. Flattened primers are not a reliable indicator, measuring case head expansion is deeply flawed, and the other signs kick in around 70 KPSI. Primers fall out at about 80 KPSI.
So what do you work up to?
You do need a chronograph.
Some powder/cartridge combinations reach a point where more powder does not produce more average velocity, but does produce more variation. Working up a load involves making sure you are not in that condition.
As long as increments of powder are producing regular increments of velocity, you are not in that condition.
Given that, find the load you like below the "book" maximum velocity for that powder and bullet. Chamber geometry, bullet mass, cartridge length, etc all drive pressure and pressure drives velocity. Velocity is very highly correlated with peak pressure, and is the best indicator most of us have.
Working up to pressure signs is ineffective. Flattened primers are not a reliable indicator, measuring case head expansion is deeply flawed, and the other signs kick in around 70 KPSI. Primers fall out at about 80 KPSI.
So what do you work up to?
You do need a chronograph.
Some powder/cartridge combinations reach a point where more powder does not produce more average velocity, but does produce more variation. Working up a load involves making sure you are not in that condition.
As long as increments of powder are producing regular increments of velocity, you are not in that condition.
Given that, find the load you like below the "book" maximum velocity for that powder and bullet. Chamber geometry, bullet mass, cartridge length, etc all drive pressure and pressure drives velocity. Velocity is very highly correlated with peak pressure, and is the best indicator most of us have.
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Since I’m unlikely to ever have to drop the hammer on a primer and seek the most velocity/energy/etc, I have always worked toward a specific goal for each cartridge. The only two that I come close to “pushing” are 357 and 44 and they aren’t top loads.
223, I’ve found best accuracy and plenty of power for my use at up to 200 fs below factory.
223, I’ve found best accuracy and plenty of power for my use at up to 200 fs below factory.
This is what I’m asking. Load to accuracy and velocity… I get it. If you’re shooting an AR, do you have reliable pressure signs? What are you looking for? Velocity data is hard to find for 16” or shorter barrels from various powders.
My go/no go line is when I start seeing shiny spots from the ejector.
Ranger99
Member
^ ^ ^ ^ ^ ^ ^ this right here ^ ^ ^ ^ ^ ^
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The rest is minor details
