Cylinder bolt timing issues with a 1858 NA Uberti

Pond, James Pond · July 14, 2021, 04:40 AM

This concerns a BP Uberti 1858 replica.

If I cock the hammer, the cylinder turns, as you'd expect.

As it does, the cylinder lock pops up to hold the cylinder in place. So far so good.

However, it does so early.

In fact it does so in such a way that only half the width of the stop is over the cylinder recess. The rest slams into the metal of the cylinder and only pops into place once the hammer is pulled a little further before cocking fully and the cylinder has been pulled in line with the barrel.

Now when it's all locked up the cylinder is perfectly aligned with the barrel, so that tells me that playing around with the cylinder hand (? The part that pushes on the star and makes the cylinder rotate below the hammer) is a bad idea.

So the only bits I can imagine can be fettled to affect only the point when the stop springs up are the stop itself and a raised, circular section on the side of the hammer that the stop engages with one of the prongs on the stop.

My question is two-fold:
First, am I right in saying that the easier of the two to work is the stop itself?

Second, am I right in saying that the inner prong of the stop that engages with that circular section of the hammer would need to be longer to delay the stop being released?

I have ordered two spare stops that I can work with and should have them by next Monday.

I'm assuming/hoping that they have not been filed down the way the one in the revolver is, meaning I have some prong length to work with.

If that is the case I'm thinking of taking off very small amounts until the bolt releases.

Pond, James Pond · July 15, 2021, 02:12 PM

In the interests of saving bandwidth, here is a link to a post in The Smithy.

It relates to how I could delay when the bolt is released on a 1858 New Army revolver, which presently jumps too early and is hammering my cylinder.

If you think you can help, please do have a clickety click and read through.

Thanks!

Hawg · July 15, 2021, 03:06 PM

The bolt is rising late. It should rise a full bolt width before the cylinder notch.

Pond, James Pond · July 15, 2021, 03:35 PM

So the entire bolt surface should strike cylinder wall before any of it moves over the retention slot?

I ask a the research I’ve done suggested that if the slots are at 60 degrees, the bolt should rise at 55 degrees.

And if so, does that mean I must then shorten the bolt prong?

(Don’t wanna go filin’ stuff that doesn’t need filin’!)

**4V50 Gary** · July 15, 2021, 10:26 PM

Yes, the tail of the bolt (on Colts the cylinder stop is called a bolt) if falling off the hammer too soon causing the bolt to pop out of the window and engaging the cylinder prematurely. I would see if I could extend the existing bolt tail. Alternatively the camming surface of the hammer could be a small piece (shim stock) soldered onto. Take measurements first.

tangolima · July 15, 2021, 11:58 PM

The bolt needs to pop up well in advance of the slot. Otherwise it could miss the slot if the cylinder rotates fast, like in a gun battle when the hammer is cocked fast. The disadvantage is it drags on the cylinder, causing drag marks.

I wouldn't mind the drag mark myself.

-TL

Sent from my SM-N960U using Tapatalk

Pond, James Pond · July 16, 2021, 12:57 AM

Unless as I’m misunderstanding, there seem to be contradictions of opinion on when it should rise to meet the cylinder.

I don’t mind ring marks but it seems to be peening material into the cylinder slot from the impact.

If I made the bolt rise sooner I wonder if it would actually dent the cylinder surface after a while.

What about weakening the bolt spring?
That way, wherever and whenever it lands, it would pound the cylinder quite as hard.
Worth trying?
Hidden risks?

**4V50 Gary** · July 16, 2021, 07:03 AM

Tangolima raises a valid point for revolvers. You want the bolt to pop up in time to arrest the cylinder's rotation. Too late and you don't get lockup. If you're into fan firing then you should accept it because you're working the action at Clint Eastwood speeds. In law enforcement reliability was #1 concern and we wanted the cylinder stop/bolt to pop up halfway between chambers well in advance of the forward leading edge. We accepted the drag mark (and didn't care).

If however your concern is comestics, you want the bolt to pop up in forward leading edge to the cylinder notch. That means you're willing to accept a slower bolt release. If that's the case, then the bolt tail is dropping off shelf of the hammer camming surface prematurely and you want to slow that down. It's not a matter of adjusting that two finger spring either.

(BTW, the Colt Python's bolt works similarly but off the shelf of the rebound lever instead of the hammer).

Pond, James Pond · July 16, 2021, 01:03 PM

Cosmetics are not my concern. The ring mark doesn't bother me.

Longevity is my concern.

If the collective opinion is that things are fine as they are (it rotates and locks up correctly aligned) then great: I'm just aware of the cylinder slot edge worn inward from the slam of the bolt hitting it.

All that kinetic energy connecting on a point that is unsupported on one side (the slot's edge) and focussed through an area that is only half of the bolt, if that makes sense.

So, I have no problem speeding it up so that the bolt rises sooner, hitting the wall midway between retention slots. A drag ring isn't a worry, I just don't want to damage the revolver functionally.

RC20 · July 16, 2021, 02:43 PM

James:

This gets into serious smith work. It should not be peening.

You might look to see if its still trying to drive the cylinder further after the latch pops into the slot (cylinder stop).

A short remedy might be to cock it gently, and depending on resources that might work long term as well.

One of those you need to have the expertise as well as it in front of you to really assess.

Pond, James Pond · July 16, 2021, 04:54 PM

Honestly, I think I need to provide pictures. Perhaps I'm not using the right terms to describe what I'm seeing but pictures will have to wait until Monday when I am back.

But if you imagine the cylinder slot, the edge where the bolt strikes, has been made concave to a degree by the repeated impacts, (as far as I can tell...). And, to my eye, that edge of the cylinder slot has bulged as a result to a small degree: the material being displaced had to go somewhere...

But the long and the short of it is that one prong that cams on the hammer is either too short (if I want the bolt to drop virtually straight into the cylinder slot) or too long (if I want to have it drop halfway between any two given cylinder stops so that it is sure to engage the cylinder as it turns.

The latter option is fine by me as long as it is fine by the gun: it is certainly easier to shorten a metal part than it is to lengthen it.

I incidentally found another thread on here that seems to show similar cylinder marks although I have to read it more carefully. I'll link it here as the images show similar effects as on my Uberti: posts #29-31 in particular (second page)

**4V50 Gary** · July 16, 2021, 07:01 PM

There is a certain sequence in fitting a bolt. If you're serious about learning, might I suggest you enroll in the NRA Summer Gunsmithing Tuning SA Revolver Class? They just had one at Trinidad State.

Pond, James Pond · July 17, 2021, 01:26 AM

That is quite a long way away from me! I live in Estonia!

But thanks all the same!

**4V50 Gary** · July 17, 2021, 06:22 AM

Suggest you buy Jerry Kuhnhausen's book on Colt Single Action Revolvers.

The tricky thing about Colt (or Rem 1858) is that if you mess up one thing, multiple things can be adversely affected.

Pond, James Pond · July 17, 2021, 07:30 AM

Quote:

The tricky thing about Colt (or Rem 1858) is that if you mess up one thing, multiple things can be adversely affected.

Well that’s not very encouraging!!

But ok… I’ll look into it.

With two spare bolts ordered though I can at least note their different dimensions and how the gun behaves as a result.

Then I can decide if I’m to take metal file to gun surface.
I will try to remove the peening with a deburring tool though.

**Aguila Blanca** · July 17, 2021, 10:16 AM

Quote:

Originally Posted by 4V50 Gary

If however your concern is comestics, you want the bolt to pop up in forward leading edge to the cylinder notch.

But the 1858 doesn't have the progressive lead-in to the cylinder notches.

https://www.uberti-usa.com/sites/def...y-revolver.png

**4V50 Gary** · July 17, 2021, 11:00 AM

Yeah, but it uses the Colt's lockwork.

Pond, James Pond · July 19, 2021, 04:13 PM

I'm no longer sure if what my Uberti is doing is bad, acceptable or normal.

I'm also no longer sure of what my goal should be.

Tonight I had some time to myself now that the kids have nodded off and I took calipers to my 1858.

I measured the width of all 6 cylinder slots:
4.07mm, 3.96mm, 4.09mm, 4.03mm,4.07mm and 4.04mm. Those measurements are all around 0.16 inches, for reference.

Then I measured where the peening was at its worst in each cylinder:
3.85mm, 3.88mm, 3.87mm, 3.84mm, 3.91mm and 3.93mm.

So there's between 0.1 and 0.2mm of peened material on the edges of the cylinder stops.

I also measured the width of the bolt: 3.96mm, so it would have problems getting a firm in placement in 4 of the 6, although it's never felt like it didn't lock up nicely.

But when new it would have slipped comfortably into 5 of the 6.

Finally, I measured the amount of rotation that the cylinder underwent to go from the point when the bolt sprung up and hit the cylinder to when it dropped into the stop.

That measurement was about 0.027 inches (changed the units for that one).

So really the bolt it being released with 85% of the bolt already over the cylinder gap. All the inertia of the bolt is being transferred through about 15% of the bolts surface area and connecting with the very edge of the cylinder stop.

This makes the peening less of a surprise.

So... with all that information, can the BP or SA shooters of TFL draw any conclusions as to what, if anything, I should consider doing?

Shorten the bolt prong to make it release earlier or leave it alone, and just clean up the edges of the stop?

**4V50 Gary** · July 19, 2021, 05:19 PM

Don't mess with the bolt.

tangolima · August 2, 2021, 06:51 PM

Sounds like the bolt is rather late to pop up. It hits the leading edge of the slot and causes peening. The bolt should pop up much earlier, way in advance of the slot's leading edge. It pops and hit the cylinder somewhere between the slot, then it drags along and pops into the slot.

It is not difficult to adjust. But you don't sound very proficient with colt's lock work. I would suggest letting the professionals to earn their keep. Make sure you find someone who knows his trade.

-TL

Sent from my SM-N960U using Tapatalk

Pond, James Pond · August 3, 2021, 03:55 AM

Colt SA specialists in Estonia a much like hen's teeth, I'm afraid.

Hawg · August 3, 2021, 05:21 AM

It should not pop up halfway between the notches but it does need to pop up at least a bolt width before the notch. It is not supposed to pop up directly into the notch.

tangolima · August 3, 2021, 09:31 AM

Quote:

Originally Posted by Pond, James Pond

Colt SA specialists in Estonia a much like hen's teeth, I'm afraid.

I see. I may be able to give referral to good info, if you want to try your hands on the revolver. It is tricky, but not impossible. PM me when you have a chance.

-TL

Sent from my SM-N960U using Tapatalk

July 15, 2021, 03:35 PM	#4
Pond, James Pond Senior Member Join Date: July 12, 2011 Location: Top of the Baltic stack Posts: 6,079	So the entire bolt surface should strike cylinder wall before any of it moves over the retention slot? I ask a the research I’ve done suggested that if the slots are at 60 degrees, the bolt should rise at 55 degrees. And if so, does that mean I must then shorten the bolt prong? (Don’t wanna go filin’ stuff that doesn’t need filin’!) __________________ When the right to effective self-defence is denied, that right to self-defence which remains is essentially symbolic. Freedom: Please enjoy responsibly.

July 15, 2021, 10:26 PM	#5
4V50 Gary Staff Join Date: November 2, 1998 Location: Colorado Posts: 21,847	Yes, the tail of the bolt (on Colts the cylinder stop is called a bolt) if falling off the hammer too soon causing the bolt to pop out of the window and engaging the cylinder prematurely. I would see if I could extend the existing bolt tail. Alternatively the camming surface of the hammer could be a small piece (shim stock) soldered onto. Take measurements first. __________________ Vigilantibus et non dormientibus jura subveniunt. *Molon Labe!*

July 16, 2021, 12:57 AM	#7
Pond, James Pond Senior Member Join Date: July 12, 2011 Location: Top of the Baltic stack Posts: 6,079	Unless as I’m misunderstanding, there seem to be contradictions of opinion on when it should rise to meet the cylinder. I don’t mind ring marks but it seems to be peening material into the cylinder slot from the impact. If I made the bolt rise sooner I wonder if it would actually dent the cylinder surface after a while. What about weakening the bolt spring? That way, wherever and whenever it lands, it would pound the cylinder quite as hard. Worth trying? Hidden risks? __________________ When the right to effective self-defence is denied, that right to self-defence which remains is essentially symbolic. Freedom: Please enjoy responsibly.

July 16, 2021, 07:03 AM	#8
4V50 Gary Staff Join Date: November 2, 1998 Location: Colorado Posts: 21,847	Tangolima raises a valid point for revolvers. You want the bolt to pop up in time to arrest the cylinder's rotation. Too late and you don't get lockup. If you're into fan firing then you should accept it because you're working the action at Clint Eastwood speeds. In law enforcement reliability was #1 concern and we wanted the cylinder stop/bolt to pop up halfway between chambers well in advance of the forward leading edge. We accepted the drag mark (and didn't care). If however your concern is comestics, you want the bolt to pop up in forward leading edge to the cylinder notch. That means you're willing to accept a slower bolt release. If that's the case, then the bolt tail is dropping off shelf of the hammer camming surface prematurely and you want to slow that down. It's not a matter of adjusting that two finger spring either. (BTW, the Colt Python's bolt works similarly but off the shelf of the rebound lever instead of the hammer). __________________ Vigilantibus et non dormientibus jura subveniunt. *Molon Labe!*

July 16, 2021, 01:03 PM	#9
Pond, James Pond Senior Member Join Date: July 12, 2011 Location: Top of the Baltic stack Posts: 6,079	Cosmetics are not my concern. The ring mark doesn't bother me. Longevity is my concern. If the collective opinion is that things are fine as they are (it rotates and locks up correctly aligned) then great: I'm just aware of the cylinder slot edge worn inward from the slam of the bolt hitting it. All that kinetic energy connecting on a point that is unsupported on one side (the slot's edge) and focussed through an area that is only half of the bolt, if that makes sense. So, I have no problem speeding it up so that the bolt rises sooner, hitting the wall midway between retention slots. A drag ring isn't a worry, I just don't want to damage the revolver functionally. __________________ When the right to effective self-defence is denied, that right to self-defence which remains is essentially symbolic. Freedom: Please enjoy responsibly.

July 14, 2021, 04:40 AM	#1
Pond, James Pond Senior Member Join Date: July 12, 2011 Location: Top of the Baltic stack Posts: 6,079	Cylinder bolt timing issues with a 1858 NA Uberti This concerns a BP Uberti 1858 replica. If I cock the hammer, the cylinder turns, as you'd expect. As it does, the cylinder lock pops up to hold the cylinder in place. So far so good. However, it does so early. In fact it does so in such a way that only half the width of the stop is over the cylinder recess. The rest slams into the metal of the cylinder and only pops into place once the hammer is pulled a little further before cocking fully and the cylinder has been pulled in line with the barrel. Now when it's all locked up the cylinder is perfectly aligned with the barrel, so that tells me that playing around with the cylinder hand (? The part that pushes on the star and makes the cylinder rotate below the hammer) is a bad idea. So the only bits I can imagine can be fettled to affect only the point when the stop springs up are the stop itself and a raised, circular section on the side of the hammer that the stop engages with one of the prongs on the stop. My question is two-fold: First, am I right in saying that the easier of the two to work is the stop itself? Second, am I right in saying that the inner prong of the stop that engages with that circular section of the hammer would need to be longer to delay the stop being released? I have ordered two spare stops that I can work with and should have them by next Monday. I'm assuming/hoping that they have not been filed down the way the one in the revolver is, meaning I have some prong length to work with. If that is the case I'm thinking of taking off very small amounts until the bolt releases. __________________ When the right to effective self-defence is denied, that right to self-defence which remains is essentially symbolic. Freedom: Please enjoy responsibly. Last edited by Pond, James Pond; July 14, 2021 at 06:08 AM. Reason: Clarifies firearm in question

July 15, 2021, 02:12 PM	#2
Pond, James Pond Senior Member Join Date: July 12, 2011 Location: Top of the Baltic stack Posts: 6,079	Cylinder bolt timing issues with a 1858 NA Uberti In the interests of saving bandwidth, here is a link to a post in The Smithy. It relates to how I could delay when the bolt is released on a 1858 New Army revolver, which presently jumps too early and is hammering my cylinder. If you think you can help, please do have a clickety click and read through. Thanks! __________________ When the right to effective self-defence is denied, that right to self-defence which remains is essentially symbolic. Freedom: Please enjoy responsibly.

July 15, 2021, 03:06 PM	#3
Hawg Senior Member Join Date: September 8, 2007 Location: Mississippi Posts: 16,190	The bolt is rising late. It should rise a full bolt width before the cylinder notch.

July 15, 2021, 11:58 PM	#6
tangolima Senior Member Join Date: September 28, 2013 Posts: 3,834	The bolt needs to pop up well in advance of the slot. Otherwise it could miss the slot if the cylinder rotates fast, like in a gun battle when the hammer is cocked fast. The disadvantage is it drags on the cylinder, causing drag marks. I wouldn't mind the drag mark myself. -TL Sent from my SM-N960U using Tapatalk

July 16, 2021, 02:43 PM	#10
RC20 Senior Member Join Date: April 10, 2008 Location: Alaska Posts: 7,014	James: This gets into serious smith work. It should not be peening. You might look to see if its still trying to drive the cylinder further after the latch pops into the slot (cylinder stop). A short remedy might be to cock it gently, and depending on resources that might work long term as well. One of those you need to have the expertise as well as it in front of you to really assess. __________________ Science and Facts are True whether you believe it or not

July 16, 2021, 04:54 PM	#11
Pond, James Pond Senior Member Join Date: July 12, 2011 Location: Top of the Baltic stack Posts: 6,079	Honestly, I think I need to provide pictures. Perhaps I'm not using the right terms to describe what I'm seeing but pictures will have to wait until Monday when I am back. But if you imagine the cylinder slot, the edge where the bolt strikes, has been made concave to a degree by the repeated impacts, (as far as I can tell...). And, to my eye, that edge of the cylinder slot has bulged as a result to a small degree: the material being displaced had to go somewhere... But the long and the short of it is that one prong that cams on the hammer is either too short (if I want the bolt to drop virtually straight into the cylinder slot) or too long (if I want to have it drop halfway between any two given cylinder stops so that it is sure to engage the cylinder as it turns. The latter option is fine by me as long as it is fine by the gun: it is certainly easier to shorten a metal part than it is to lengthen it. I incidentally found another thread on here that seems to show similar cylinder marks although I have to read it more carefully. I'll link it here as the images show similar effects as on my Uberti: posts #29-31 in particular (second page) __________________ When the right to effective self-defence is denied, that right to self-defence which remains is essentially symbolic. Freedom: Please enjoy responsibly.

July 16, 2021, 07:01 PM	#12
4V50 Gary Staff Join Date: November 2, 1998 Location: Colorado Posts: 21,847	There is a certain sequence in fitting a bolt. If you're serious about learning, might I suggest you enroll in the NRA Summer Gunsmithing Tuning SA Revolver Class? They just had one at Trinidad State. __________________ Vigilantibus et non dormientibus jura subveniunt. *Molon Labe!*

July 17, 2021, 01:26 AM	#13
Pond, James Pond Senior Member Join Date: July 12, 2011 Location: Top of the Baltic stack Posts: 6,079	That is quite a long way away from me! I live in Estonia! But thanks all the same! __________________ When the right to effective self-defence is denied, that right to self-defence which remains is essentially symbolic. Freedom: Please enjoy responsibly.

July 17, 2021, 06:22 AM	#14
4V50 Gary Staff Join Date: November 2, 1998 Location: Colorado Posts: 21,847	Suggest you buy Jerry Kuhnhausen's book on Colt Single Action Revolvers. The tricky thing about Colt (or Rem 1858) is that if you mess up one thing, multiple things can be adversely affected. __________________ Vigilantibus et non dormientibus jura subveniunt. *Molon Labe!*

July 17, 2021, 11:00 AM	#17
4V50 Gary Staff Join Date: November 2, 1998 Location: Colorado Posts: 21,847	Yeah, but it uses the Colt's lockwork. __________________ Vigilantibus et non dormientibus jura subveniunt. *Molon Labe!*

July 19, 2021, 04:13 PM	#18
Pond, James Pond Senior Member Join Date: July 12, 2011 Location: Top of the Baltic stack Posts: 6,079	Should I be concerned? I'm no longer sure if what my Uberti is doing is bad, acceptable or normal. I'm also no longer sure of what my goal should be. Tonight I had some time to myself now that the kids have nodded off and I took calipers to my 1858. I measured the width of all 6 cylinder slots: 4.07mm, 3.96mm, 4.09mm, 4.03mm,4.07mm and 4.04mm. Those measurements are all around 0.16 inches, for reference. Then I measured where the peening was at its worst in each cylinder: 3.85mm, 3.88mm, 3.87mm, 3.84mm, 3.91mm and 3.93mm. So there's between 0.1 and 0.2mm of peened material on the edges of the cylinder stops. I also measured the width of the bolt: 3.96mm, so it would have problems getting a firm in placement in 4 of the 6, although it's never felt like it didn't lock up nicely. But when new it would have slipped comfortably into 5 of the 6. Finally, I measured the amount of rotation that the cylinder underwent to go from the point when the bolt sprung up and hit the cylinder to when it dropped into the stop. That measurement was about 0.027 inches (changed the units for that one). So really the bolt it being released with 85% of the bolt already over the cylinder gap. All the inertia of the bolt is being transferred through about 15% of the bolts surface area and connecting with the very edge of the cylinder stop. This makes the peening less of a surprise. So... with all that information, can the BP or SA shooters of TFL draw any conclusions as to what, if anything, I should consider doing? Shorten the bolt prong to make it release earlier or leave it alone, and just clean up the edges of the stop? __________________ When the right to effective self-defence is denied, that right to self-defence which remains is essentially symbolic. Freedom: Please enjoy responsibly.

July 19, 2021, 05:19 PM	#19
4V50 Gary Staff Join Date: November 2, 1998 Location: Colorado Posts: 21,847	Don't mess with the bolt. __________________ Vigilantibus et non dormientibus jura subveniunt. *Molon Labe!*

August 2, 2021, 06:51 PM	#20
tangolima Senior Member Join Date: September 28, 2013 Posts: 3,834	Sounds like the bolt is rather late to pop up. It hits the leading edge of the slot and causes peening. The bolt should pop up much earlier, way in advance of the slot's leading edge. It pops and hit the cylinder somewhere between the slot, then it drags along and pops into the slot. It is not difficult to adjust. But you don't sound very proficient with colt's lock work. I would suggest letting the professionals to earn their keep. Make sure you find someone who knows his trade. -TL Sent from my SM-N960U using Tapatalk

August 3, 2021, 03:55 AM	#21
Pond, James Pond Senior Member Join Date: July 12, 2011 Location: Top of the Baltic stack Posts: 6,079	Colt SA specialists in Estonia a much like hen's teeth, I'm afraid. __________________ When the right to effective self-defence is denied, that right to self-defence which remains is essentially symbolic. Freedom: Please enjoy responsibly.

August 3, 2021, 05:21 AM	#22
Hawg Senior Member Join Date: September 8, 2007 Location: Mississippi Posts: 16,190	It should not pop up halfway between the notches but it does need to pop up at least a bolt width before the notch. It is not supposed to pop up directly into the notch.