Relative strength between percussion models

[M. De Land]

A thought I wanted to share before we got to far off topic into the unmentionalbles and subsequently axed, is that in open frame guns the arbor has two weak points where as the solid frame has one. They both have the threads (arbor and barrel) under tension but only the open frame has a wedge slot ,arbor end, that can fail although very rarely. Wither or not it bottoms out is irrelavent to strength in my opinion.
I intend to Ransom rest test and see if it has any accuracy relevance.

 

[smoothshooter]

A thought I wanted to share before we got to far off topic into the unmentionalbles and subsequently axed, is that in open frame guns the arbor has two weak points where as the solid frame has one. They both have the threads (arbor and barrel) under tension but only the open frame has a wedge slot ,arbor end, that can fail although very rarely. Wither or not it bottoms out is irrelavent to strength in my opinion.
I intend to Ransom rest test and see if it has any accuracy relevance.

Why the concern about strength?

 

[45D]

Why the concern about strength?

For open tops that are going to shoot bp, it's not really a strength thing, it's a "don't let the revolver self destruct" thing. The destruction comes from "incorrect build" which all reproductions have except for Pietta's of late ( they saw fit to fix the problem which some simply refuse to believe the problem is real . . . but that's been hashed out and explained again and again ).
The o.t. revolver of today is plenty "strong" enough for its intended use. Over time, shooting max loads with heavy bullets will take it's toll and depending on the build tolerances may happen sooner rather than later.
So, that is the reason for the "arbor correction ", to allow your inexpensive revolver to not turn into trash but to become part of a growing collection of different revolvers.

The strength is an issue if you're going to use "heavier than bp" loads. Cap and ball is not anywhere near 20,000 psi pressures so, it stands to reason that "good tests" be performed to verify that kind of regiment.
That said, tests are ongoing and the Uberti platform is robust enough for well over the mentioned load.

If you're looking for strength or durability, the answer for both is same. That's the whole reason for this information. To expand knowledge and allow options folks may have questions about.

Mike

 

[M. De Land]

Why the concern about strength?

No concern at all if we use black powder or suitable subs.

 

[necchi]

I intend to Ransom rest test and see if it has any accuracy relevance.

Ok. What "accuracy relevant" variable, are you going to test for? There are dozens of possible variables that affect accuracy.

 

[M. De Land]

Ok. What "accuracy relevant" variable, are you going to test for? There are dozens of possible variables that affect accuracy.

A known accuracy load tested with and without arbor end fit in a Ransom Rest and again off sand bags on a bench. Both are standard accuracy checks for hand guns with good loads.

 

[Sean E Bug]

they are both adequate for the forces applied to them. I prefer the open tops as they are easier to clean. I for one see the "short arbors" as a feature not a bug. lets you set the barrel gap and in the design the wedge is an intentional wear point that is easy to replace.

 

[45D]

they are both adequate for the forces applied to them. I prefer the open tops as they are easier to clean. I for one see the "short arbors" as a feature not a bug. lets you set the barrel gap and in the design the wedge is an intentional wear point that is easy to replace.

Ummmmm, maybe the wear comes from the arbor not fitting . . .
Are you saying Colt didn't understand his own design?

Mike

 

[Sean E Bug]

Ummmmm, maybe the wear comes from the arbor not fitting . . .
Are you saying Colt didn't understand his own design?

Mike

No I am saying that was an intentional part of the design. Colt was one of the leaders when it comes to developing interchangeable parts but all of his guns still required hand fitting by gunsmiths as the manufacturing was nowhere near the ability to hold the tolerances people are accustomed to today. the wedge is actually really well thought out way of being able to adjust the revolver as it is used and experiences wear. When the revolver is fired compressive forces from the front of the arbor slot and the fame of the barrel when will gradually narrow the wedge. this is not a problem as the wedge is tapered and is simply pushed in a little farther to achieve the desired adjustment. when the wedge can be fully inserted into the frame it was time for it to be replaced. keep in mind this is something literally any blacksmith of the era could do. If one is smart and learns not use a hammer to adjust the wedge it really isn't a problem.

 

[nkbj]

When you make bullets longer the available space for powder is decreased.
If using black powder there's little cause worry about heavy bullets being too much for the Colt design revolvers. There is however a very real concern over damaging the wedge slot if a poorly designed bullet is forced into the chambers.

 

[smoothshooter]

No I am saying that was an intentional part of the design. Colt was one of the leaders when it comes to developing interchangeable parts but all of his guns still required hand fitting by gunsmiths as the manufacturing was nowhere near the ability to hold the tolerances people are accustomed to today. the wedge is actually really well thought out way of being able to adjust the revolver as it is used and experiences wear. When the revolver is fired compressive forces from the front of the arbor slot and the fame of the barrel when will gradually narrow the wedge. this is not a problem as the wedge is tapered and is simply pushed in a little farther to achieve the desired adjustment. when the wedge can be fully inserted into the frame it was time for it to be replaced. keep in mind this is something literally any blacksmith of the era could do. If one is smart and learns not use a hammer to adjust the wedge it really isn't a problem.

My percussion revolvers are set up to where only thumb pressure is required to seat the wedge into it’s slot, and only a light tap with the butt end of a screwdriver or similar object is required to release it.
Have had no wear issues with my two Pedersoli’s (1851 Navy and 1860 Army) after thousands of shots loaded mostly with maximum loads.

 

[45D]

No I am saying that was an intentional part of the design. Colt was one of the leaders when it comes to developing interchangeable parts but all of his guns still required hand fitting by gunsmiths as the manufacturing was nowhere near the ability to hold the tolerances people are accustomed to today. the wedge is actually really well thought out way of being able to adjust the revolver as it is used and experiences wear. When the revolver is fired compressive forces from the front of the arbor slot and the fame of the barrel when will gradually narrow the wedge. this is not a problem as the wedge is tapered and is simply pushed in a little farther to achieve the desired adjustment. when the wedge can be fully inserted into the frame it was time for it to be replaced. keep in mind this is something literally any blacksmith of the era could do. If one is smart and learns not use a hammer to adjust the wedge it really isn't a problem.

Well, you can " pretend" that was a design feature but it was not. The arbors of the originals in fact fit all the way to the bottom of the arbor hole . . . a little "detail" that all reproduction manufacturers left out.
Having a loose wedge was never a design feature and isn't a good idea. The very idea of "adjusting" the endshake makes absolutely no sense and wouldn't make any to the average owner/soldier. The obvious setup would be a "fixed" endshake so you would have the same setup every time the revolver is assembled without "adjusting" anything . . . and that's exactly what Colt did.

The company's instructions didn't say "drive the wedge in and adjust the clearance/endshake. It was simply "drive the wedge in . . . or "drive the wedge out . . . for cleaning or assembly.

Shooting a Walker or Dragoon with max loads and a loose ( in "just so") wedge will eventually upset material on the barrel assy and beat the arbor end . . . even to the point of failure. I know this from experience and I here it all the time from customers.
I also know that once corrected, there's no more beat up wedges, no more upsetting barrel material and the endshake is a constant.
Something else I know, if a wedge starts out loose, it won't tighten itself up, it'll just get looser and THAT'S where the quickest damage happens . . . to wedge and revolver.
Hundreds and hundreds of corrected open top revolvers (not to mention my own personal revolvers that shoot much higher pressures with no problems) are a testament to Colts design done correctly , as these revolvers are used in competition, paper punching, hunting, self defense. I would definitely NOT test the platform like I am if the wedge was the "do all alignment tool " . . . it is not. It is simply a tensioning device joining two assemblies together so they will act as a single unit. The original wedges were numbered to the revolver and not considered a "consumable" lol. Anybody have an original "wedge bag"?

Mike

 

[45D]

My percussion revolvers are set up to where only thumb pressure is required to seat the wedge into it’s slot, and only a light tap with the butt end of a screwdriver or similar object is required to release it.
Have had no wear issues with my two Pedersoli’s (1851 Navy and 1860 Army) after thousands of shots loaded mostly with maximum loads.

That's amazing . . . when I do the thumb pressure thing I can never get the endshake that I set. Maybe I'm just not strong enough. I can even smack the wedge with my palm and take a measurement and nope . . . a good smack with my machinest's hammer and there ya go . . . ! Done deal.

Mike

 

[M. De Land]

A thought I wanted to share before we got to far off topic into the unmentionalbles and subsequently axed, is that in open frame guns the arbor has two weak points where as the solid frame has one. They both have the threads (arbor and barrel) under tension but only the open frame has a wedge slot ,arbor end, that can fail although very rarely. Wither or not it bottoms out is irrelavent to strength in my opinion.
I intend to Ransom rest test and see if it has any accuracy relevance.

The main difference in the two platforms as I see it is not one of strength really as they are both adequate to the task but of design concept. One is a rigid design and the other a "flex" as I like to describe it idea that when set up correctly allows repeatable movement which translates to accuracy. The rigid (solid frame) designs accomplish this from minimizing movement.
In and open frame design there are more places of movement because of tolerances required for hand assembly/disassembly.
Wither or not the arbor fits the end of the barrel well or not it is never going to be or act as a solid unit with the barrel assembly because of the tolerance required for slip fit between the two. No matter how hard the end of the arbor and the well are mashed up against one another the none connected joint is still present and will not prevent some lateral (side to side) movement between the two under load of firing pressure.
I don't believe arbor end fit contributes to strength but am keen to see if it effects accuracy positively. Mine have been plenty accurate with short arbors.

 

[Stantheman86]

The function of the barrel wedge is NOT to take up the force of recoil.

Colt designed the revolvers to have a properly fitted arbor that would make the revolver one solid, strong, locked up unit when assembled. The barrel wedge has one job, to hold the gun together. It is not to "set barrel / cylinder gap" . This is set at the factory when the gun is fitted. It was never intended to be a design feature.

Before Pietta went to their new production methods that allowed them to have properly fitted arbors, I had an older Pietta .36 1851 Navy. It had a short arbor.

The guns were cheap back in 2005 or so, the gun was a 90s production if I recall, and I figured it was a steel frame so it was good to go. I topped off my chambers with Pyrodex P and crammed a Buffalo Bullet on top. I put some of the bullets in upside down because they were easier to load.

After a few days of doing this, the wedge slot had become badly peened and the gun was sloppy. No way should 30 or 40 gr loads loosen up a steel frame Navy. The barrel wedge had been taking the brunt of the force of the recoil and peening the slot. If the arbor was properly fitted, this would not have happened.

I did the same with one of my brand new Piettas, a .36 Navy Brasser, and fired max loads of Pyrodex and a conical bullet, for a whole day at the range and the gun is as tight and undamaged as when I got it. Because the new CNC machining and assembly allows the gun to fit as Sam Colt intended.

My Walker has the short arbor, two trips to the range with 40 gr charges, the two pins that go into the holes in the barrel, on the frame, became sloppy and I had to peen the pins to tighten them. I could feel the slop in the barrel , where before I fired it , it had not done this. The short arbor must have allowed some kind of barrel twisting or battering of these pin holes. A Walker will beat itself to death if the short arbor isn't fixed. This is a fact.

Uberti saves production costs by not worrying about it because the average buyer won't shoot these guns enough to care or ever notice a problem.

 

[45D]

Stantheman86, your story is the same as so many others . . .
What's amazing is - fix the arbor fit and all those things go away.
I can't for the life of me see how the wedge made just "so so" and fitted "just perfect" could be enough of a "piece" to keep a revolver (especially the size of a Dragoon or Walker or even as small as a pocket pistol) from wrecking itself!

When fitting the arbor, you first have to have contact at the frame/barrel lug (where the 2 locating pins are). That is the first contact point. After that your just zeroing in on the target headspace. When you get that done and drive the wedge in, you have imparted serious tension on - the first contact point ( which locates in 4 directions), the rear of the Barrel wedge slot at the wedge contact point (which additionally locates the barrel on both sides of the arbor as well as stabilizing the wedge in place), and probably the most important contact point ( since it defines the endshake) which is the end of the arbor. Those contact points (the arbor itself being the main structure) allow the forces generated at firing to flow uninterrupted throughout the whole of the revolver which allows the revolver to respond as if it were a single unit and remain undamaged.
A nice machined wedge would be nice but the factory wedges work just fine.

For shooting high pressure loads (20kpsi +) a "captured wedge" is extra insurance that the wedge CAN'T get loose. One shot with those pressures alone may call for a new wedge !!

Mike

 

[M. De Land]

Stantheman86, your story is the same as so many others . . .
What's amazing is - fix the arbor fit and all those things go away.
I can't for the life of me see how the wedge made just "so so" and fitted "just perfect" could be enough of a "piece" to keep a revolver (especially the size of a Dragoon or Walker or even as small as a pocket pistol) from wrecking itself!

When fitting the arbor, you first have to have contact at the frame/barrel lug (where the 2 locating pins are). That is the first contact point. After that your just zeroing in on the target headspace. When you get that done and drive the wedge in, you have imparted serious tension on - the first contact point ( which locates in 4 directions), the rear of the Barrel wedge slot at the wedge contact point (which additionally locates the barrel on both sides of the arbor as well as stabilizing the wedge in place), and probably the most important contact point ( since it defines the endshake) which is the end of the arbor. Those contact points (the arbor itself being the main structure) allow the forces generated at firing to flow uninterrupted throughout the whole of the revolver which allows the revolver to respond as if it were a single unit and remain undamaged.
A nice machined wedge would be nice but the factory wedges work just fine.

For shooting high pressure loads (20kpsi +) a "captured wedge" is extra insurance that the wedge CAN'T get loose. One shot with those pressures alone may call for a new wedge !!

Mike

Good stuff guys I'm enjoying the civil discussion and challenge to my own ideas as this is how we improve our abilities.
One of the stress factors that few shooters are aware of and was pointed out by the pin slop is the torque imparted from bullet rotation. This is where the wedge thickness is critical as well as tight pins. The pins being father from the center of bore have the greater leverage to counteract torque and have to be tightly fit to accomplish this task or the arbor slot gets the whole load. If the pins are loose and wedge is not fit tightly in the arbor slot vertically than it gets a run at the arbor slot on a radial axis. My guess is that this is at least one of the causes of arbor end failure.
The barrel torque will be in the direction of the rifling and not counter to it as some think.
Another thing that is important is a very close fit at the lug and frame. One should not be able to see any day light between the two at the joint or all the torsional stress is on the pins alone and any gap will make them "woller" out eventually.

 

[Jim in Wisconsin]

All this sure makes the Remington design sound good to me!

 

[smoothshooter]

Well, you can " pretend" that was a design feature but it was not. The arbors of the originals in fact fit all the way to the bottom of the arbor hole . . . a little "detail" that all reproduction manufacturers left out.
Having a loose wedge was never a design feature and isn't a good idea. The very idea of "adjusting" the endshake makes absolutely no sense and wouldn't make any to the average owner/soldier. The obvious setup would be a "fixed" endshake so you would have the same setup every time the revolver is assembled without "adjusting" anything . . . and that's exactly what Colt did.

The company's instructions didn't say "drive the wedge in and adjust the clearance/endshake. It was simply "drive the wedge in . . . or "drive the wedge out . . . for cleaning or assembly.

Shooting a Walker or Dragoon with max loads and a loose ( in "just so") wedge will eventually upset material on the barrel assy and beat the arbor end . . . even to the point of failure. I know this from experience and I here it all the time from customers.
I also know that once corrected, there's no more beat up wedges, no more upsetting barrel material and the endshake is a constant.
Something else I know, if a wedge starts out loose, it won't tighten itself up, it'll just get looser and THAT'S where the quickest damage happens . . . to wedge and revolver.
Hundreds and hundreds of corrected open top revolvers (not to mention my own personal revolvers that shoot much higher pressures with no problems) are a testament to Colts design done correctly , as these revolvers are used in competition, paper punching, hunting, self defense. I would definitely NOT test the platform like I am if the wedge was the "do all alignment tool " . . . it is not. It is simply a tensioning device joining two assemblies together so they will act as a single unit. The original wedges were numbered to the revolver and not considered a "consumable" lol. Anybody have an original "wedge bag"?

Mike

What loads are you using to get “ higher pressures “?

 

[45D]

What loads are you using to get “ higher pressures “?

If you'll look at a very recently "locked" thread, you'll find the answer. Everyone ( at this point) knows I don't (and haven't for 20yrs) shoot bp. But what I DO shoot with these platforms gives me the ability to test not only the "durability" of design but the "strength" of design as well. Since max bp charges won't overload the revolver, max loads are just that. That makes the arbor correction for open top revolvers important for durability. On the other hand, it would be very easy to overload . . . pretty much any revolver with the type components I use . Therefore, I have the ability to use "known" pressures as a test for strength of design . . . along with which manufacturers revolvers "hold up" best over time / number of shots fired and so on. This should shed some light on the importance of "what I shoot" as far as a test for the platforms we enjoy and discuss on these forums.
After all, what's good for the "unmentionable" stuff is "Overkill " for the "smoky stuff" !!! Lol

Mike