Leading in Ruger SBH

Catfish, the question is the differential of throat to barrel dimensions. If the throat is too small yes the bullet will friction fit as is commonly spoken of. But it gets sized in the throat at firing to the throat dimension, which may be as small as the bore. So there is no secondary sizing as the bullet enters the bore. There “should” be two sizing events that occur for there to be a quality fit. Others have mentioned the throats needed to be opened up, this is due to undersized throats, not oversized bore. Once first sizing occurs, there needs to be .001+ in secondary sizing at barrel for the theoretical proper fit. You may have small throats. You are sizing once, when bullet hits bore, it bounces down the barrel as it is NOW a small bullet, fit the throat but is loose in bore. A squeeze, then another squeeze. Theres a forcing cone at work in there too and 6 diff. throats. You indicated a .001 diff between throats. I would guess that if you isolated the largest throat, the leading would be mitigated to SOME EXTENT by only using that throat for a # of rounds. Of course that is conjecture but founded in some fact. It would not be a fix, just a verification of ailment.

Hope that helps some.

Also the slower powders will “typically” assist in the fix for poor bullet fit, but I can't give a solid reason. Leading will be less, velocities higher for obvious reasons. There will be more unburnt powder, that is how pistols consume 4227 especially with lighter bullets. 300gr bullets, same crimp, less powder waste. 180 gr bullets, same crimp, flame thrower events occur. I doubt the change from 2400 to 4227 will render any additional help. Going from bulleye to 4227, thats when you see the biggest improvement.

I have had the same problem with my Dan Wesson 357 ma 8 inch. I have NOT opened the throats. Thats coming and it WILL fix my gun. Slower powder makes it better, might as well push the bullet hard, that helps too and will typically render better accuracy with the conditions at hand. You'll lead the same amount, maybe a tad less. Don't use LLA, use a stick lube. My bullets fit tight, like I have to push them in to get the round to chamber at times. Not hammer them but push with my thumb. That will be fixed too with the rethroating for all 6 pipes. My ruger sp101 has an even smaller throating of all 5 pipes. Bullets that fit in DW, I couldn't hammer them in the Ruger. Seems like a RUGER problem as others have indicated. BUT my sp101 was designed to shoot 125 gr JHP's very fast to destroy human organs at close range so I don't bother to fix the Ruger. It is not meant to consume large amount of PB without a raincoat.