Firing pin may be hitting edge of hole. Advice please.

[Seth.45]

Hi. While cleaning my relatively new (400 rounds through it) .45 cal Uberti 1873 Cattleman II single action revolver, I noticed a notch in the hole that the firing pin goes into that seems to indicate that the firing pin is striking the edge to some degree. I've attached a picture. I'm new to the single action revolver world, so my question is mainly just: should I be worried? Thanks in advance.

 

[DPris]

In the Colt design, there are two things that deal with this.

One is a loose firing pin that can be guided into entering the funneled hole in a centered approach, to allow for variations in manufacturing tolerances.
You don't want a solid firing pin.

The other is a removable recoil plate, or firing pin hole bushing, that can be replaced with a new one if off-center firing pin hits create enough wear to become a problem.
Uberti single-actions typically don't have that bushing, which means if the firing pin strike continues far enough off center to wear a notch in the frame, it CAN become an ignition problem.
And the frame is pretty much junk, unless you have somebody mill & install a plate/bushing.

It's a shortcut that Uberti's taken for many years.
Denis

 

[243winxb]

https://www.uberti-usa.com/1873-cattleman-ii-revolver
Could a light bevel be put on the face of the hole? This would guide the tip of the pin?

But first, be 100% sure that contact is being made.

My guess.

Very interesting safety feature , a Retractable Firing Pin.

 

[243winxb]

https://thefiringline.com/forums/showthread.php?t=562199 Found this , with photos.

By Driftwood Johnson. He is also a member here.

 

[DPris]

As DJ mentions in his older post, IF the planets align wrong, your gun CAN build up a burr around the hole on the inside of the frame.
This can get so bad it interferes with cylinder rotation when loaded, as he also mentions.
That's easily addressed, with a small fine file, as far as that goes, but you've still got the original problem that displaced material to that point.

This can be caused by a firing pin that's not moving enough as it's funneled into that hole, it can be caused by excessive dry-firing.
Your gun should have enough play built into it so the loose firing pin doesn't impact too hard on the frame in that hole.

Uberti tolerances do vary, though, and if they stack against you, your gun COULD possibly develop a problem.
The hole could be machined slightly off spec, the firing pin could be, the hammer could be.

NOT saying ALL Ubertis do this, but it's been known to happen.

The potential solution if it progresses to become problematic is to find somebody who can successfully install a Colt recoil plate (bushing).
That's iffy & will probably cost more than the gun's worth, IF you can find somebody who can do it right.

I've seen one Uberti with a recoil plate somebody'd stuck in it.
It didn't hold under repeated firing, started to move backwards into the frame to where primers were backing out into the recess & binding the cylinder.
That was a CAS gun, it was never fired with hot, or even standard, loads.

As you shoot your gun, clean that hole with swabs & a pipe cleaner after each session, so you can clearly see what's going on there.
Take the cylinder out & watch for any signs of a burr being created around the hole on the inside of the frame.

If the firing pin's hitting the frame that hard, it may eventually bust the pin.
It may continue to create/enlarge a notch.
It may create a burr.
It may create off-center primer strikes.

Clean it, watch it.
If it develops any of those signs, you may have a problem gun.

That hole is just one area where Uberti takes the cheap route.
They get away with it most of the time, but Colt realized a helluva long time ago that if wear does occur, it's much cheaper to replace a small recoil plate than an entire frame.
Denis

 

[Driftwood Johnson]

Howdy

I had to grab an Uberti Cattleman to see exactly what you have taken a photo of.

That is the hole through the frame, where the firing pin goes through, viewed from the rear, or hammer side.

First off, FIRST BEING SURE THE GUN IS UNLOADED, cock the hammer and grab the firing pin. It should wiggle a little bit. It should wiggle a little bit more vertically than horizontally. This is because, as mentioned, the firing pin has to 'find its way' through the hole. The hole is drilled straight through, the firing pin is traveling in an arc to go through the hole, and the firing pin will probably rub along the hole somewhere as it finds its way through.

In your case, there is a raised burr around the smaller diameter of the hole. This is caused because something is displacing the relatively soft metal of the frame. Probably the firing pin.

I just checked my one remaining Uberti Cattleman, and the hole is quite clean, without a raised burr.

Then I checked a couple of 2nd Gen Colts. The through hole on the Colts has a nice conic section that helps the firing pin find its way through the hole. One of the niceties of a Colt.

It appears to me your firing pin may be striking the hole in the frame. What I mean by that is the physical stop that prevents the hammer from moving any further forward should be the hammer itself striking the frame. Not the firing pin coming to a stop against the frame. There should be a tiny bit of leeway.

Try this. Cut a thin strip of paper. Insert the strip of paper into the slot in the frame above the firing pin hole and gently lower the hammer all the way. Then pull out the piece of paper. What happens? If there is some resistance to pulling out the strip of paper, then the hammer is bearing against it, as it should. If instead the strip of paper slides out easily, with no resistance, then that part of the hammer is not contacting the frame. Instead, the firing pin may be acting as the physical stop. Take a good look at the firing pin. Is the conical part of the pin a uniform color, or can you see a ring formed around the pin where the blue has been worn off by striking the frame.

Paper is around .003 or .004 thick. If you can find a piece of shim stock .001 thick, you can test it even further.

Bottom line is, I wouldn't worry about it too much. When you fire a cartridge, the firing pin will be cushioned slightly as it dents the primer, so it will be cushioned slightly just before it hits the frame.

If you can take your revolver apart, you can take a drill bit slightly smaller in diameter than the large diameter of the hole, and carefully remove the burr, by gently spinning the drill in your fingers. DO NOT USE A POWER DRILL!

Bottom line is, the firing pin should protrude from the frame a minimum of .045 and a maximum of .056. You can get a good eyeball of this by laying a drill bit of known diameter next to the firing pin as it protrudes through the frame. I suspect if that burr is allowed to build up enough, it may prevent the firing pin from striking a primer with the proper amount of protrusion to fire a primer every time.

If you remove the burr, don't go overboard. Check your firing pin projection first, before removing any metal.



Regarding the face of the hole on the other side, where it protrudes through the frame, I have found that with an Uberti, which lacks a pressed in hardened insert, the firing pin can drag a burr and build it up on the inside of the frame. This can eventually cause problems with clearance of live rounds. Here is the hole on an Uberti Cattleman that I had to do a little bit of surgery to, to remove a burr. It there is a raised burr in that area, your fingernail will detect it.






Colts have a hardened bushing pressed into the frame to prevent such a burr forming.