RBHarter
West Central AR
Several yr ago I absorbed a dozen or so threads and waded through the boredom of repetition in different phrasing of the information and the threads that just ended about the time the shooter was getting to the good parts ........
What I got out of it ,
Use iron moulds , zinc doesn't play nice with aluminum .
Copper laden zinc works best . Zamak 3 ?
Lead contamination below 5% removes the piping issues .
No need for checks , coating or lubes .
Way lighter than lead .
Use a separate dedicated pot for zinc alloy .
I have a couple of candidate bullets I'd like to try .
A 27-135F . Should come in 89-91 gr if math and memory serves , 65-70 if my second guessing is right .
There was some talk about about weight vs case intrusion for extracting load data , so what start with the slowest powder at a start charge for an X bullet halfway between what the zinclettes weigh and what they were cast as ? If a lead 27-130 weighs 135 and it's zinker weighs 90 gr try 4198 for a 115 gr Barnes X in a 6.8 SPC and see what happens ?
I've thought about paper patched in zinc but it seems counter intuitive . So maybe a straight wall cartridge would be a better starting place . How fast would a 300 gr 405 design go with a 50kpsi limit ?
Will the "free" velocity offset the lost mass ? I don't care for my intent because I don't intend to use it on live targets in fact just as light short range training ammo . Look , feel , rapid energy loss .
What I got out of it ,
Use iron moulds , zinc doesn't play nice with aluminum .
Copper laden zinc works best . Zamak 3 ?
Lead contamination below 5% removes the piping issues .
No need for checks , coating or lubes .
Way lighter than lead .
Use a separate dedicated pot for zinc alloy .
I have a couple of candidate bullets I'd like to try .
A 27-135F . Should come in 89-91 gr if math and memory serves , 65-70 if my second guessing is right .
There was some talk about about weight vs case intrusion for extracting load data , so what start with the slowest powder at a start charge for an X bullet halfway between what the zinclettes weigh and what they were cast as ? If a lead 27-130 weighs 135 and it's zinker weighs 90 gr try 4198 for a 115 gr Barnes X in a 6.8 SPC and see what happens ?
I've thought about paper patched in zinc but it seems counter intuitive . So maybe a straight wall cartridge would be a better starting place . How fast would a 300 gr 405 design go with a 50kpsi limit ?
Will the "free" velocity offset the lost mass ? I don't care for my intent because I don't intend to use it on live targets in fact just as light short range training ammo . Look , feel , rapid energy loss .
