.56-50 Spencer Bullet casting/sizing

[Sweetwater Jack]

New to the .56-50, I have a Lyman 515139 mould. I assume I don't want to shoot "as cast" and should run the fresh bullets through my Star Lube/Sizer.   Question: What size dies?  .512" or something else between .512" and .515" ??  Using Lyman Loading Dies and Starline .56-50 Brass.    Thanks,  Sweetwater Jack.

[Herbert]

It depend on what modle 56-50 you are loading for ,if it is a Ami Sports spencer from .512 to .515 will be fine ,if it a original spencer you will have to slug the bore and go .002 over size for best acuracy

[Fox Creek Kid]

Always slug the bore on EVERY gun. Usually the gun will shoot best with a bullet 0.001" over groove diam. best. However, if the gun is a low pressure type AND you are using real BP loads & not smokeless or "faux" BP then you can shoot the biggest soft alloyed bullet that will chamber. My gun slugs at 0.512" and I shoot bullets "as cast" which are at 0.513". 

[Sweetwater Jack]

Thanks Guys!  It's a Taylor's Armi-Sport, and I'll slug the bore tomorrow..... Much Obliged!   Sweetwater