Blackwater
08-26-2005, 08:28 PM
I've got a Saeco #745 mould for my .45/70 BPCR 1885 Browning. It's a 533 gr. sort'a semi-pointed Creedmoor type bullet with a small flat point. I've always gotten good bullets from Saeco moulds, and this was my first casting experince for a really heavy bullet.
The first time I cast with it, I used WW's with @ 2% tin added in the form of 50/50 solder. Got spunky and cast some 350 or so. 70% of them were @ 15 gr. light, and had voids in the base. THAT was a BIG disappointment, and I subsequently remelted them and gave the lead another chance in another mould. The alloy cast fine in another, lighter pistol bullet mould, so it wasn't necessarily the alloy.
I'd read where many big bullet BPCR casters recommended using only plain lead/tin alloys to get the best and most consistent bullets, so tried that, using @ 30:1 lead/tin. These bullets came out just fine, and gave me something I could use effectively in the BPCR.
I guess I really have two questions here. One, what is it about the antimonial alloy that made the bullets get a void with that alloy, while the lead/tin alloy did well; and Two, would enlarging the sprue hole in the mould likely let it cast void-free bullets with WW's, and if so, what would be the effect on the plain lead/tin alloy casting? Any cure recommendations would be appreciated.
BTW, it's a 2-cav. mould. They didn't have a single cavity when I ordered, so I got the 2-cav version. Thanks for any help here. I AM learning!
The first time I cast with it, I used WW's with @ 2% tin added in the form of 50/50 solder. Got spunky and cast some 350 or so. 70% of them were @ 15 gr. light, and had voids in the base. THAT was a BIG disappointment, and I subsequently remelted them and gave the lead another chance in another mould. The alloy cast fine in another, lighter pistol bullet mould, so it wasn't necessarily the alloy.
I'd read where many big bullet BPCR casters recommended using only plain lead/tin alloys to get the best and most consistent bullets, so tried that, using @ 30:1 lead/tin. These bullets came out just fine, and gave me something I could use effectively in the BPCR.
I guess I really have two questions here. One, what is it about the antimonial alloy that made the bullets get a void with that alloy, while the lead/tin alloy did well; and Two, would enlarging the sprue hole in the mould likely let it cast void-free bullets with WW's, and if so, what would be the effect on the plain lead/tin alloy casting? Any cure recommendations would be appreciated.
BTW, it's a 2-cav. mould. They didn't have a single cavity when I ordered, so I got the 2-cav version. Thanks for any help here. I AM learning!