Adding to the Arsenal!

[tpelle]

I just scored a new Pietta 1851 Navy for $219! I've been wanting one for some time, and happened to catch a sale at Cabela's. With the way prices have been going, this may be the cheapest I'll ever find one.

I already have two "good" Pietta 1860 Armies and an older short-arbor "hangar queen" , plus a Pietta 1863 Remington. I shoot these replica revolvers more than my modern handguns.

When I get this one I'll do what I usually do, which is perform that last 10% of the assembly process that the Italians don't do - fit the cylinder bolt so that it doesn't peen the cylinder locking notches, mainly, as well as install Treso nipples.

 

[CraigC]

Sounds good! I've been watching them, waiting for a good deal on a stainless 1858 and a Walker.

...fit the cylinder bolt so that it doesn't peen the cylinder locking notches...

What is involved in doing this?

 

[tpelle]

It's pretty well detailed in the "Tuning a Pietta for Competition" articles. Basically, Pietta cuts the locking notches in the cylinder to a width of about 0.143", but then makes the cylinder bolt out of 0.155 stock. They then leave the leg on the bolt that rides on the hammer cam too long, with the result that the bolt is released just when the hammer reaches full cock. What happens then is that the too-wide bolt crashes up into the cylinder locking notches, and in short order hammers the locking notches over.

Not only does this mean that the cylinder locking notches are eventually damaged, but the cylinder is not really locked. It is only held in place by one side of the bolt, and the other side is held by the hand, whose entire job should properly be to rotate the cylinder. But what happens next is that, when you pull the trigger and the hammer falls, the hammer pulls the hand back down. But the hand spring is still pushing the hand against the ratchet on the back of the cylinder, and the potential exists that the cylinder may rotate backwards just a little. So when the chamber fires, the ball then crashes into one side of the forcing cone. Not good, as it likely stresses the arbor unnecessarily.

It's easy to test for this. Just cock the unloaded revolver, and while slowly lowering the hammer, use your other hand to try to rotate the cylinder backwards. If you can do so, then your bolt has to be refitted.

If the cylinder notches are too beat up, then you may need a new cylinder, which Cabela's usually sells for $49.

But don't try to refit your bolt or clean up the notches with a Dremel. Go to Home Depot and buy a set of Nicholson precision files.

What is supposed to happen is that, first, the bolt should come off of the cam well before the hammer reaches full cock and before the cylinder aligns with the barrel. The bolt then snaps up into the lead-in grooves and is pressed up by the pressure of the bolt spring - that's why those grooves are there. Then, when the hammer reaches full cock and the cylinder aligns with the bore, the bolt is pushed up into the locking notches gently and without causing damage.

By the way, I don't do the hand spring replacement that the tuning article details. So far I've never had a hand spring break.

 

[hillbilly matt]

hey tpelle do the '60 colts have the same problem ?

btw nice score on your new shooter

 

[tpelle]

Yes. I believe it's a common problem with all Pietta revolvers. It seems that Uberti pistols come with short arbors, while Piettas have poorly fitted bolts.

I still favor Pietta over Uberti, as it's a whole lot easier to correct bolt fit and tuning, needing nothing more than a $10 set of files from Home Depot and your kitchen table, than it is to correct a too short arbor. And the job is really easy to do., and is really well documented in the "Tuning a Pietta for Competition" write ups on the web.

The really important thing is to do it right away with a new revolver before the locking notches get hammered to death.

Getting the bolt timing - that is, getting the bolt to drop into the lead in groove instead of directly into the locking notch - takes longer, as you have to file a little, then put the bolt in and test it, then take it out and file some more, then repeat until you're satisfied. (And make sure that your Dremel tool is never in the same room.)

But these revolvers have very simple mechanisms, easy to understand, and if you booger something up VTI Gun Parts has replacements at reasonable prices and fast delivery.

 

[BowerR64]

I think mine are starting to get buggered up

Is there some images of what you need to file to correct it?

Do i have this labled right?

 

[4v50 Gary]

Bolt is coming up too slow.

 

[CraigC]

Might need some adjustment to prevent the peening on the back side of the bolt notch but it's timed correctly.

 

[tpelle]

Is that a Pietta? The timing looks pretty good as is, honestly, but it looks like the bolt itself may be a little thick.

I'd suggest removing the bolt and the cylinder, and then test the bolt to see if it will fit in the cylinder notches. Test all six, as there might be some notches that are wider or thinner. Also note that the bolt fits into the notches at a little bit of an angle, as the bolt is not exactly centered in the frame.

 

[BowerR64]

I tinkered with it a little today i dont think i messed it up. Now i heat the bolt drop a hair before full cock. The bolt appears to be dropping into the lead in now.

I also took a little off the left side of the bolt so its slightly thinner only where it drops into the notch.

 

[tpelle]

Yeah, that's what you have to do - take a little off the left side of the bolt, but only the portion that extends above the water table of the frame.

I found the easiest way to do it is to mark the bolt at the level of the water table, then remove the bolt and lock it into a machinist vise. Then I use a precision Nicholson file with a safe edge to narrow it down.