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I did a little experiment yesterday that drove home the point about working up from less than max loads.
I'm testing Hornady 150 grain GMX bullets in my .30-06 (Winchester 670, 24: barrel) with Remington cases, IMR 4064 and CCI Large Rifle primers.
Hornady's load data is based on essentially the same rifle but different cases and primers. It shows powder charges from 44.7-55.6 grains, adn MVs between 2,500 and 3,000 FPS.
I loaded 11 Remington cases with charges ranging from 50-55 grains in half grain increments. My MVs ranged from 2891 to 3124 FPS, or roughly 140 FPS faster than Hornady's data with the same charge of IMR 4064.
When I removed the primers, I saw pressure signs starting at 52 grains with a bit of flattening and a tiny bit of cratering. At 55 grains, both flattening and cratering were more pronounced. The wasn't ever sticky.
Hornady claims their monolithic bullets can be loaded just like their clad bullets of the same weight, including a jacketed soft point (#3031) for which there is test data in the Lyman reloading book. Lyman's tests used between 48 and 53 grains of powder to get speeds that were closer to mine with the same charge. They use Winchester cases and a Universal receiver. I thought I'd see similar results but since I used some different components, my mileage DID vary.
If you don't want to follow the ladder test or other methods for developing loads or if you don't have a chronograph, you might want to do as I did to check for pressure signs before deciding you can start with max book loads.
I'm testing Hornady 150 grain GMX bullets in my .30-06 (Winchester 670, 24: barrel) with Remington cases, IMR 4064 and CCI Large Rifle primers.
Hornady's load data is based on essentially the same rifle but different cases and primers. It shows powder charges from 44.7-55.6 grains, adn MVs between 2,500 and 3,000 FPS.
I loaded 11 Remington cases with charges ranging from 50-55 grains in half grain increments. My MVs ranged from 2891 to 3124 FPS, or roughly 140 FPS faster than Hornady's data with the same charge of IMR 4064.
When I removed the primers, I saw pressure signs starting at 52 grains with a bit of flattening and a tiny bit of cratering. At 55 grains, both flattening and cratering were more pronounced. The wasn't ever sticky.
Hornady claims their monolithic bullets can be loaded just like their clad bullets of the same weight, including a jacketed soft point (#3031) for which there is test data in the Lyman reloading book. Lyman's tests used between 48 and 53 grains of powder to get speeds that were closer to mine with the same charge. They use Winchester cases and a Universal receiver. I thought I'd see similar results but since I used some different components, my mileage DID vary.
If you don't want to follow the ladder test or other methods for developing loads or if you don't have a chronograph, you might want to do as I did to check for pressure signs before deciding you can start with max book loads.
