The SAECO Lead Hardness Tester lets you positively identify the hardness of your cast lead bullets, verifying they’re safe to shoot and won’t damage your valuable firearm. You can cast bullets from scrap lead and check their hardness so you can shoot them with complete confidence. Or check the hardness of your black powder cast bullets to ensure proper seating in the rifling and consistent accuracy for BPCR competition. Just insert the bullet into the aluminum housing, turn the hardened steel indenter until it stops, then read the depth of penetration off the vernier scale to determine the hardness. The tester is calibrated from 0 to 10 using the SAECO scale. A hardness of at least 6 is required for medium velocities in handguns, while a reading of over 8 works best for magnum handgun bullets or gas-checked rifle bullets. (For reference, wheel weights usually test between 7 and 9, and linotype normally reads a 10.) An indispensable tool for anybody serious about bullet casting.
Sinclair, Issue:3B, Page:127