Bigslug
10-05-2012, 10:31 PM
I fired up the new mold today - manufacture dated 5/12. Since there's so much discussion of what this mold number originally was, what it morphed into, what it currently is, and what variations have spun off it, I thought it might be helpful to get the numbers from the current Lyman offering out there for any interested parties.
I cast them of what is estimated to be 23-1 range scrap, the air-cooled ingots for which tested at 9.75 BHN. Water-quenched, the boolits are about 13-14 BHN.
OAL of boolit: .729-731" depending on how clean the sprue cut.
Diameter of rear driving band: .358"
Diameter of front driving band: .354"
Depth of lube groove: .025" (diameter of boolit in the lube groove is .308")
Width of lube groove: .095" at the bottom, .130" at the surface
Front of crimp groove to meplat: approximately .370"
I made a couple of dummy rounds with a few .357 cases of varying lengths. When seated to the crimp groove on a case .005 over the standard trim-to length of 1.28", this gave me a COAL of 1.655". If I add rim thickness to the 1.61" cylinder of my GP100, I get 1.6640 - not much room at all, but it WOULD work.
On a Smith 640-1 with a 1.6" cylinder and a Ruger SP101 with a 1.58" cylinder, seating to the crimp groove is not going to work with the case at trim-to length, BUT the dummy I made on a case trimmed to about 1.24" will (though shorter for the Ruger would be better).
I made a third dummy with a 1.28" case with the brass crimped over the front driving band. This gave the shortest COAL at 1.545" and will handily work in all of the above guns. While not as sexy looking as they are when seated at the crimp groove, I did realize one serious advantage of this approach - the front driving band of the boolit is totally protected from any damage that might occur from pocket carry in speed strips or speed loaders.
EDIT: Oh yeah, with this alloy - 164 grains.
Hope that's useful to somebody. :drinks:
I cast them of what is estimated to be 23-1 range scrap, the air-cooled ingots for which tested at 9.75 BHN. Water-quenched, the boolits are about 13-14 BHN.
OAL of boolit: .729-731" depending on how clean the sprue cut.
Diameter of rear driving band: .358"
Diameter of front driving band: .354"
Depth of lube groove: .025" (diameter of boolit in the lube groove is .308")
Width of lube groove: .095" at the bottom, .130" at the surface
Front of crimp groove to meplat: approximately .370"
I made a couple of dummy rounds with a few .357 cases of varying lengths. When seated to the crimp groove on a case .005 over the standard trim-to length of 1.28", this gave me a COAL of 1.655". If I add rim thickness to the 1.61" cylinder of my GP100, I get 1.6640 - not much room at all, but it WOULD work.
On a Smith 640-1 with a 1.6" cylinder and a Ruger SP101 with a 1.58" cylinder, seating to the crimp groove is not going to work with the case at trim-to length, BUT the dummy I made on a case trimmed to about 1.24" will (though shorter for the Ruger would be better).
I made a third dummy with a 1.28" case with the brass crimped over the front driving band. This gave the shortest COAL at 1.545" and will handily work in all of the above guns. While not as sexy looking as they are when seated at the crimp groove, I did realize one serious advantage of this approach - the front driving band of the boolit is totally protected from any damage that might occur from pocket carry in speed strips or speed loaders.
EDIT: Oh yeah, with this alloy - 164 grains.
Hope that's useful to somebody. :drinks: