.454 cylinder throats

[jgh4445]

I just aquired an almost NIB 2nd Gen Colt SAA. The cylinder throats all measure between .454 and .455. The end where you insert the cartridge is .480 on all charge holes. With 7 gr of 231, and a .452 Keith boolet from straight WW, it shoots OK. OK like, one ragged hole at 7 yds, a group like a baseball at 15 and like a softball at 25. I was thinking a boolet measuring .454 might give better accuracy. Is there anything I can add to the WW to get it to fill out more? Is there a .454 mold out there?

[Beagle333]

You could powdercoat them. That usually adds about .002" to the diameter.

[runfiverun]

you could lap your mold out .002 if you have the patience.
I'd just go to accurate molds and order one that pours out at 455.

[DougGuy]

The 454190 is a good mold and usually drops around .456" ~ .457" so you could size it to fit with a light drag fit in your throats. This would be proper for your gun. Also, a softer alloy will slug up easily and fill the throat before the boolit even clears the cylinder so keep that in mind. If you can scratch it with a thumbnail, or even dig a thumbnail in, it should work pretty good for you with soft lube or even SPG lube.

I wouldn't be shooting any harder than 50/50+2% WW/Pure lead with a bit of tin added to fill out corners. 20:1 should also work. I have a Uberti with .4565" throats and I am having great results with the 454190 cast pretty soft, sized .456" and lubed with SPG.

[jgh4445]

Thanks Doug. Sounds like a plan. I can do 20:1 tin to pure lead easily. Sure do like my Keith mold though. Maybe I could lap it out like was suggested above. Now I gotta go search for "how to lap" lol. I do see a 454190 in my near future though.

[DougGuy]

I think NOE made a 454190 improved with a crimp groove, this would be an excellent choice as they drop .456" or better.

Tom at Accurate Molds has a 454190 clone, and also an improved as well. The 45-250D is the clone:

http://www.accuratemolds.com/bullet_detail.php?bullet=45-250D-D.png

The 45-250F is the improved with crimp groove design but I am not sure there is an actual link to the photos of it. You would have to ask for it but it would look something like the uppermost photo in GLL's post:

http://castboolits.gunloads.com/showthread.php?164107-Where-to-crimp-Lyman-454190&p=1834860&viewfull=1#post1834860