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View Full Version : Casting Tara Corp Mag alloy, 92pb, 6sb, 2sn



labop
12-28-2020, 11:18 AM
I started out at 710F and got some shrinkage mid bullet. Lowered the temp incrementally to 660 with the same results. Came back up to 775 which eliminates the shrink but now have whiskers, base is frosted and slow process time as the sprue must cool longer. Any words of experience in casting this alloy? Thanks

ShooterAZ
12-28-2020, 11:37 AM
775 is too hot in my opinion. My optimum alloy temps have generally run right around 725* What boolit are you casting, and what type of mold are you using?

labop
12-28-2020, 12:04 PM
Yes 775F seems to hot me. The bullet is 40 caliber, 400 grains in a steel mold.

Vegas Vince
12-28-2020, 12:30 PM
I use many Lee molds as well as others & 650 to 660 works. Good fill & no frosting. Most I can cycle 3 times a minute. Largest boolit is 310 gr.

labop
12-28-2020, 03:32 PM
I'm thinking now that the hole in the sprue plate is too small. I hesitate to modify it as it casts so well with 16-1 alloy. I am using a dipper, I might try bottom feed.