.38 Short Colt heeled bullet smokeless loads for conversion cylinder?

[curator]

I have an Uberti Colt 1851 "Navy" revolver for which I have bought a cartridge conversion cylinder. I know the groove diameter of the bore on this gun is .375 and .38 Special bullets are .357, so I purchased a proper "heeled" bullet mould from LBT so I could make cartridges that were available for these early cartridge conversion revolvers. The bullet casts at 130 grains and .376-.376 with a .357-.358 heel that fits in the trimmed .38 Special cases. Trimming cases so the loaded round does not protrude from the front of the cylinder results in a Black powder capacity of 20 grains of FFFg.

While I am probably going to mainly use real black powder, occasionally I may want to use this revolver at one of our air-conditioned indoor ranges using smokeless powder. At present the cartridge over-all length is 1.425". I am interested in anyone's experience with smokeless powder heeled bullet loads in .38 Colt conversion cylinders. The cylinder manufacturer suggests keeping velocities under 800 fps. I am considering a load of 3.5 grains of Bullseye or 4.0 grains of Unique.

[DeputyDuke]

Your smokeless loads sound a smidge warm to me. My wife shot a pair of Uberti 51 Richard/Mason conversions, and we shot straight black in them in 38 Long Colt. In the short case I'd be thinking more along the lines 2.5 to 3.0 grains of Bulls Eye for a smokeless load. Just my opinion.
Duke

[curator]

DeputyDuke,

Your opinion is appreciated. I thought so. myself, but working from zero load data. 20 grain FFFg loads chronograph at 750-780 fps.
Thanks!

[bedbugbilly]

First - to save you having to try 38 special to 38 Colt short length - you can buy smaller quantities than 500 at a tim of Starline from Track of the Wolf.

I load quit a few 38 Colt Short as well as 38 Colt long - not heeled bullets but conventional 120i is grain lead round nose. Your charges that you are considering are too hot IMHO. I shoot my Colt Shorts out of standard vintage 38 Special Revolvers as well as an Uberti '51 Richards & Mason conversion - the bore on it is .357 however. I normally use Red Dot or Bulls Eye. For Bulls Eye, I use 2.0 grains of Bullseye or 1.8 grains of Red Dot. If you have trimmed your 38 special brass back to 38 Colt Short length, your case volume is decreased by quite a bit. I have found that the loads I use are more than ample out of my 38s for plinking and critter killing. Personally, I would be leery of the loads you are thinking of out of a conversion cylinder - but that's just me. Like any load work up, start low and work your way up. I have even used my 38 Colt Short loads out of my 357 Hands Rifle. If you're using real BP, then load them like you would any other BP cartridge with a lightly compressed load. Good luck!

Let us know how your heeled boolit works. Thnx.

[Outpost75]

In the Colt New Army I always had satisfactory results loading soft-swaged Speer, Hornady, Winchester, Remington or Precision-Delta 148-grain HBWC .358 bullets seated in .38 Long Colt brass to 1.16" OAL with 2.7-3.0 grains of Bullseye to approximate .38 Special factory wadcutter ballistics. Simple solution works. Do the same thing in Brit .38 S&W Victory models using same bullet, OAL and powder charge with .38 S&W brass.

K.I.S.S. principle!