1849 Pocket Colt - Conversion

[tembotusk]

I have a Uberti 1849 31 caliber Pocket Colt pistol (4" barrel) with an R&B conversion for 32 S&W.

I understand the 32 S&W round might not sufficiently engage the rifling and cause accuracy issues.

What is recommended as a solution?

Reline the barrel?
Hollow base bullets?
Shoot it as is, plenty accurate?

I do my own reloading and casting.

Thanks for any input!

 

[Curator]

Get a bullet mold for .32 Short Colt. That bullet is a heeled bullet with the outside diameter the same as the OD on the .32S&W case. .310 on the heel and .318-.320 on the exposed ogive portion. The original cartridges for cap & ball conversions were made similar to .22 rim fire, with the bullet outside lubricated and bore diameter and a small "rebated" section to fit into the case mouth. Eventually folks realized that these exposed lubed bullets attracted grit and gun manufacturers switched to "inside lube bullets" seated deeply into the cartridge case, necessitating a switch to small bore size.

 

[tembotusk]

Curator, thanks for the info.

Are there commercially available molds with a .310 heel and .318 bullet size or would I need to have a mold custom made?

 

[rodwha]

If you have trouble finding a mold I highly recommend Accurate Molds who will make you most anything to want.

 

[tembotusk]

I have looked at Accurate Molds and your size info will be very helpful if I go that route.

 

[EljaySL]

Those actually shoot pretty decent groups once you get the load dialed in. I'd only do the conversion if you really wanted to run on smokeless for some reason or are just looking for a project.

 

[tembotusk]

The range I use is indoors and I'll be using Trail Boss powder. I have converted all my Colts for ease of use and clean up.

Curator give me some great info to follow up on and I'm hoping someone else will share what they have done with their 1849 conversion to ensure accurate fire.

 

[tembotusk]

Another Question:

I pushed a 32 caliber bullet through the barrel to see how it fit. The slug did not drop through and needed to be pushed through. The barrel left very light rifling marks on the slug. Looking down the barrel with the slug in place, I could see light along the groves.

Would this light touch of the rifling be enough to stabilize the bullet in flight?

 

[rodwha]

Unless there's a good bit of obturation, enough to fill those grooves, you'd suffer from pressure bleed-off giving you lower velocities.

 

[tembotusk]

Rodwha, that makes sense. I could see light around the bullet which means gasses would get through as well.

I measured the R&D cylinder exit holes and they measured .314, the bullet at its mid point measured .314. That means even if I had a custom mold made with a wider diameter bullet, it would get swaged down before entering the barrel.

Would relining the barrel be an option?

 

[Curator]

If gas can leak past the bullet via the unfilled grooves you will get lower velocity and possibly severe leading. Hot gasses from smokeless powder will strip off lead particles and deposit them in the bore which the bullet will run over and iron on. If your cylinder's chamber throats are smaller than groove diameter, they need to be reamed out to groove plus .001 for best results. In most original cap & ball cartridge conversions there was no chamber "throat" only the bored-through chambers. The original cartridges had bullets with the same diameter as the outside diameter of the cartridge case.

 

[tembotusk]

I measured the breach end of the conversion cylinder is comes in at .340. If the balance of the cylinder is drilled out, a true .32 size bullet could be used. Interesting.