61 conversion

[bigted]

I have had my 61 colt made by Pietta with the short 5.5 inch barrel. been wanting to do a conversion on it so I ordered a Howell converter cylinder for 38 colt. received it today and in the excitement I neglected another rifle I was foolin with sooo ... went and finished up the rifle project and came back to the Howell cylinder.

I tried some 38 special brass in it just to see what the chambers were like and dang if they didn't fit just rite. so I loaded up some 38's with cast 125 grain semi-wadcutters and 4 grains of unique for a speed of 730 fps or such.

loading up the cylinder ... as I always do ... I cocked it and carefully let down the hammer ... went to cock it again and it was jammed tight. gritting my teeth I began to investigate as to what happened as I had very carefully worked the action with the loaded cylinder and allowed nothing to jam up nor get the western treatment.

pulling the wedge I disassembled the revolver to see what the deal was ... re assembling without shells I was able to spin thru the cocking process at will with no jam ups.

reloading the cylinder with 5 again  I hung the wedge in but not tight just so as to see what was going on a bit further ... walla ... jammed again. the hammer resting on the empty chamber allows it to turn as cocked and function perfect BUT when allowing the hammer to rest on a live cartridge ... it jammed again.

imagine my surprise at finding that the pins ...[firing pins]... were long enough that when gently let down on a newly primed cartridge it wont allow the hammer to completely come down far enough to get set for another cycle. [hope im describing this clear enough]. so as I had seen the pins for sale ... I measured these to see what they would measure out at and they miked at .313 litely and .312 firmly on the pins.

coming back to my computer I looked up the pins for sale convinced that somehow the longer pins had been installed in my cylinder. upon finding them for sale I see that the short pins are .312 long and .365 in length for the longer ones. so I do have the correct pins in my cylinder plate.

so an inspiration hit and I found some already fired 38 special cases with the primer still in and shoved them in the cylinder to do an experiment ... I loaded 5 again and rested the hammer on the empty chamber. cocking the revolver I snapped it on the already fired cartridge ... trying to re-cock the revolver allowed me to function it thru all 5 ... snapping every one as I went. so the primer holds the pin to protrude enough to hold the hammer at rest without completion of its cycle and not enabling it to be re-cocked as it should. so thru a shooting round ... it would function I think ... as it should being that it would not jam with a full hammer swing on the primer.

I will test this tomorrow to see if it will function thru all 5 shots without any hiccups.

has anyone else done one of these conversion cylinders ... and if so ... does your Pietta Colt revolver function as it should or do you experience he same problem as I have discovered?

my expectation is that I could cock my revolver and change my mind for the shot ... and ... be able to let the hammer down on a loaded chamber for a minute and then to resume cocking and shooting ... mine will not allow me to do this ... at least not with this length firing pins.

[Captainkirk]

Ted;
I don't have the answer to your question, but have a question for you;
What sort of accuracy might you expect shoving a .357 lead bullet down a .375 bore?
Or are you planning on loading heeled bullets?
Remember; shooting a .450 lead bullet out of a .454 bore is quite a different story.

[mike116]

Well ted, I think I know of a cure, but not sure that I can type my explanation well enough. As you have already stated, with the loaded rounds in place, the hammer is not able to travel all the way forward enough when you let it down on a live round. If the hammer is not allowed to travel all the way forward, the bolt leg will not be allowed to pop up over the cam lip so that it can be in the correct position to be lowered back down into the frame and free of the cylinder notches when the hammer is once again pulled back. All that is really happening in this case is that the hand is trying to rotate the cylinder when attempting to pull the hammer back, but the bolt is remaining in the cylinder notches and causing the process to lock up.

I have had this happen on several percussion cylinders myself with new guns. They would cycle fine until I put a percussion cap on the cones. Even though the caps were fully seated, there no longer remained enough tolerance between the barrel breech face, cylinder face, the cones, and the hammer face when in the forward resting position.

The cure is to open up the tolerance somewhere along one of the relationships. For me, the easiest seems always to remove a tiny bit of metal from the hammer face.

Before doing that though, you might try shooting it some and see if the hammer face will peen back some from striking the pins in the cylinder. If it will peen, you will most likely then have enough tolerance without filing away any metal. Just load it up with 5 rounds so you can initially let the hammer down on an empty cylinder which will allow the action to fully cycle the first time that you go to cock it in order to fire the first round.

Pietta hammers are somewhat soft. The face of the hammer on my 1860 peened back in short order once I got to shooting the gun. It is peened back so far now though that I am looking at either replacing it or drilling out the face an installing a hardened insert.

I hope my jumbled words make sense.

That makes perfect sense to me Scooby.
Ted, you may want to make an insert for the hammer face from a hardened set screw while you are messing with it.  The firing pins have a tendency to peen the hammer face on those soft hammers.   You can drill and tap the hammer face in the area where the hammer contacts the pin.  Then screw in a hardened set screw and file it off to the level that works best and allows the hammer to go forward enough to cycle properly.

[bigted]

very cool. thanks fella's for the words of wisdom.

yes I do know about the 357 bullets in a 375 bore ... I plan to use the hollow base 148 grain wadcutter so that the bullet will "bump up" with the use of a snappy powder like blackpowder will do. rite now I just wanna make it go bang in a repeatable fashion ... so the ensuing leading and probably lack of accuracy is ok at the moment ... I had thought about lining the barrel to a 357 inch bore so it would remove the need for the special bullets but don't know just yet weather I want to change the complete revolver for the "newer" bore diameter.

the hammer thing sounds like the best fix for my problem but ... I would at this point want to retain the use of the original cap-n-ball cylinder so whatever I do is going to have to have the option of the change-back cylinder. Ideally I want a C&B revolver with the option of the conversion at will.

you folks are the best here. I have some contemplation of stuff to do for now on how to proceed and MAYBE ... wont have to do a dang thing as the hammer may peen back into a useable tool without having to change anything just yet ... however I will prolly have to do the hammer mod yet as the peening back will prolly ruin the C&B portion of my desires.

this is the reason I love these revolvers ... a fiddle here and a fiddle there and the tinkering goes on and on. these are rite up my alley as a Harley rider from days when you kept it running and together as the cost to have another do it was outta the mix ... so here we go again ... another project to play with while I shoot the army short barrel to keep myself amused.

thanks again and I will try to get some photo's up of this dandy.

[bigted]

well I did shoot it a bunch and the accuracy IS lacking sooo ... I ordered 500 148 grain hollow base bullets from Buff arms and just got em so I will try them in this conversion.

the accuracy with the 359 inch bullets was dismal to say the least but ... it is very fun to shoot with both blackpowder and trail boss. hopefully these hollow base bullets will do the trick ...

however I do have a 6 inch length of 357 barrel liner on the way so this will give me another project to accomplish. if any have hints on installing a liner I would appreciate the helpful hints. looks like a straight forward project to me ... just drill out the barrel to the rite diameter and shove in the liner with some green locktight bushing goop and allow to set up and install a forcing cone on the rear and a crown on the front of the barrel.

looking forward to doing this project for sure.

[Captainkirk]

Make sure you do a documentary over in the gunsmithing section!

[bigted]

you bet ... will surely do it instead of here ... thanks.