To much is made of short arbors

[GYJ]

The Army asked for a solid frame and a .45 caliber centerfire cartridge. THAT is why William Mason designed the SAA with a solid frame, chambered in the brand new .45Colt cartridge.

Let's see, percussion revolvers hover around the 10,000psi range. They also operated just fine with metallic cartridges, 12-14,000psi. The .45Colt is a 14,000psi cartridge. Tell me again what's so superior about a solid frame, in that context??? Today, with modern metallurgy and smokeless cartridges, the Colt SAA in .45Colt is considered to be safe at 21,000psi, because it is also offered as a .45ACP convertible. Likewise, thanks to Walt Kirst, the Colt open top .44 percussion guns and replicas can now also be converted to .45ACP. Tell me again what's so superior about a solid frame, in that context? The fact is that the open top design was plenty strong for the applications they were designed for......and more. It's only until we get to so-called "magnum" pressures that strength becomes an issue. At least, according to what we actually know, not just what people think because they heard it somewhere.

 

[French Colonial]

The Army asked for a solid frame and a .45 caliber centerfire cartridge. THAT is why William Mason designed the SAA with a solid frame, chambered in the brand new .45Colt cartridge.

Let's see, percussion revolvers hover around the 10,000psi range. They also operated just fine with metallic cartridges, 12-14,000psi. The .45Colt is a 14,000psi cartridge. Tell me again what's so superior about a solid frame, in that context??? Today, with modern metallurgy and smokeless cartridges, the Colt SAA in .45Colt is considered to be safe at 21,000psi, because it is also offered as a .45ACP convertible. Likewise, thanks to Walt Kirst, the Colt open top .44 percussion guns and replicas can now also be converted to .45ACP. Tell me again what's so superior about a solid frame, in that context? The fact is that the open top design was plenty strong for the applications they were designed for......and more. It's only until we get to so-called "magnum" pressures that strength becomes an issue. At least, according to what we actually know, not just what people think because they heard it somewhere.

I do not think that anyone has argued that open tops are not strong enough for what they were designed to do.

But when Elmer Kieth and John Linbaugh were on their quests to increase horsepower they did not go back to open
tops. John cut lengthened and modified solid frame pistols to stuff his cartridges in to them.

I would love to see the guys who think open tops are the stronger design cut and modify one to contain one of John's cartridges and prove us naysayers wrong. Until then they will remain on my ignore list as that is how much I value their opinions.

 

[Dale Lilly]

I’m not shooting anywhere near as often as I did only a few months ago. My practice used to be most evenings I would shoot a couple cylinders at my personal range. Clean as noted, dry the chambers and barrel and reload for the next day.

I use copper based anti seize paste. Wonderful stuff.

Yes, I’ve seen it. My plan was to retire, buy a mini mill and a lathe and begin working on these sorts of projects. I’m 77 years old, just retired and my doctor has told me I’m officially on borrowed time. Chemotherapy is no longer an option, I began to bleed internally after the second treatment and so I won’t be undertaking any further projects. Back on topic, grooving the cylinder pin seems to help but the plan was to remove the barrels on my Remingtons and mill the frame and cylinder to provide for a bushing like the Colts, S&W, etc. etc. cartridge revolvers (and Ruger Old Army @SDSmlf) Ah well… so it goes.

Bad Karma, I am praying for you. God is still in charge. When He does not heal, He gives solace. Hang in there. Dale

 

[springfield art]

Interesting thought not messing with the arbor, might save me some time getting my new Uberti 1860 tuned up . . . except I've done the work to know better.

I've tested more than 30 1860 Armies (originals, Belgian, Pietta, Uberti, ASM) in a Ransom Rest. One of the tests involves shooting at 100 yards, removing and returning the wedge and barrel assembly between shots (because I was really curious about the effect of a short arbor). Guns with a short arbor are consistently-less-consistent, with 10-shot groups sometimes approaching 2'. Guns with well-fit arbors usually run about 8-10", and short-arbor guns that are re-worked to correct the problem drop down into this range.

Another way the effects of a short arbor show up when testing in the Ransom is to shoot 5) 10-shot groups at 100 yards, removing and returning the wedge and barrel between each group. If the gun has a short arbor, POI will move around. Groups from a well-fit, or re-fit, gun will have a consistent POI.

I always respect and am impressed with guys who will do the labor-intensive testing you have done. It must take much patience. Good work!

 

[45D]

I do not think that anyone has argued that open tops are not strong enough for what they were designed to do.

The original argument was the difference in the open-top platform vs the Remington platform. I learned that if you can bend a Remington by loading/shooting too hard a lead ball but "just" shear a loading lever screw with the same lead, the "layout" of the open-top was obviously the better design for the forces involved. It's much easier to replace a screw than a frame.

Since then ( especially over this last year!), I've been able to show that a correctly setup Uberti 1860 Army is structurally capable of supporting a cylinder capable of firing 21-23K psi loads which is rather amazing as it is.

Then, all of a sudden the platform had to withstand "magnum" loads to really "prove" anything.

Funny how fast detractors can go from 0-60 !!!!

Mike

 

[GYJ]

Let's not forget that Colt has lived and died by the gov't contract for its entire existence.

I do not think that anyone has argued that open tops are not strong enough for what they were designed to do.

Then why does the subject of strength ever come up in conversations about Colt and Remington blackpowder replica guns???

But when Elmer Kieth and John Linbaugh were on their quests to increase horsepower they did not go back to open
tops. John cut lengthened and modified solid frame pistols to stuff his cartridges in to them.

Did you actually read my entire post? Miss this part?

"It's only until we get to so-called "magnum" pressures that strength becomes an issue."

Linebaugh didn't work with Colt SAA's either. Keith did and his ultimate creation was a 26,000psi .44Spl load. And we're not talking about percussion guns of 100yrs ago. In the 1930's, Colt SAA's had been proofed for smokeless and that required an improvement in the steels used and their heat treating. It also involved eliminating iron parts from the equation. The Army's request for a solid frame, for whatever reason there might've been, predated smokeless cartridges and any perceived 'need' for greater strength by 30yrs.

Let's stay in context, what "need" was there for greater strength when Colt went from the 1860 to the SAA? There was none. I illustrated this perfectly in my previous post. At that point, we were +60yrs from the .357, +80yrs from the .44Mag and +110yrs from the Linebaugh era. There is a vast chasm between percussion guns and the .500Linebaugh.

Let us also not overlook the fact that the Army's request for a .45 caliber inside lubed, centerfire cartridge also 100% necessitated a new design. Because the heeled .44Colt and Henry rimfire were the largest cartridges that would physically fit in the Open Top platform. It wasn't until Uberti enlarged the design that the .45Colt would physically fit into these guns.

People like simple answers and there isn't one. The point here is that people simply assume that they went to the solid frame because it's stronger. No evidence supports that. Quite a bit refutes it. I would wager that strength was not a consideration at all. If the solid frame was such an advantage, why would Colt submit the 1871-1872 Open Top cartridge gun to the Army at all?

 

[Snooterpup]

What part of the surface area contact don’t some folks get? The entire front surface area of the arbor in contact with the entire surface area of the arbor well verses the surface areas of the wedge and arbor slot? The solid abutment of what 45D recommends just makes common sense to me. Any pressure or stress hitting arbor to arbor well abutment have got to be far more solid than relying on the wedge to arbor slot method in my humble none gun-smith opinion.
I’m with Sam Colt and 45D.
Snoot
PS …. I could agree with the other way, but then we’d both be wrong.

 

[M. De Land]

What part of the surface area contact don’t some folks get? The entire front surface area of the arbor in contact with the entire surface area of the arbor well verses the surface areas of the wedge and arbor slot? The solid abutment of what 45D recommends just makes common sense to me. Any pressure or stress hitting arbor to arbor well abutment have got to be far more solid than relying on the wedge to arbor slot method in my humble none gun-smith opinion.
I’m with Sam Colt and 45D.
Snoot
PS …. I could agree with the other way, but then we’d both be wrong.

Lets try this example to get the point across about arbor end contact, energy transfer and strength to resist separation.
Think of how a croquette mallet transfers energy when one wishes to send there opponents ball off in the weeds. He stands on his ball anchoring it solidly (wedge anchoring arbor to barrel), makes contact with his opponents ball (end fit arbor to arbor well in barrel ), and striking his own ball transfers the energy from the mallet through his ball (which remains anchored under his foot) to his opponents and sends it flying. Would the energy be transferred if his anchored ball were not touching his opponents ball ?
There is no strength added to resist separation of barrel and arbor by end contact because of the joint between them which is only linked with the wedge. Actually using the croquette example more energy to precipitate separation is transferred" by" arbor end contact !
End contact does make a good wedge depth gauge and would prevent any chance of barrel bounce to the rear if it actually happens which I doubt very much and have seen no evidence for.

 

[M. De Land]

Lets try this example to get the point across about arbor end contact, energy transfer and strength to resist separation.
Think of how a croquette mallet transfers energy when one wishes to send there opponents ball off in the weeds. He stands on his ball anchoring it solidly (wedge anchoring arbor to barrel), makes contact with his opponents ball (end fit arbor to arbor well in barrel ), and striking his own ball transfers the energy from the mallet through his ball (which remains anchored under his foot) to his opponents and sends it flying. Would the energy be transferred if his anchored ball were not touching his opponents ball ?
There is no strength added to resist separation of barrel and arbor by end contact because of the joint between them which is only linked with the wedge. Actually using the croquette example more energy to precipitate separation is transferred" by" arbor end contact !
End contact does make a good wedge depth gauge and would prevent any chance of barrel bounce to the rear if it actually happens which I doubt very much and have seen no evidence for.

Any way it's a good "lively" discussion, thought provoking and gets us outside the box thinking !

 

[64Springer]

Come oooon page 11.

 

[SDSmlf]

listening to this dribble

The sound of dribble. Now we can read it.

 

[Gun Tramp]

I found an e-mail address for Uberti in the Instruction/Safety Manual that came with one of my percussion models:
[email protected]
Inquired about the short arbor and for whatever reason received this reply from Greg Slaughter of Cimarron Firearms:
"The question you're asking is really a question that Uberti needs to address themselves. Cimarron does not know why Uberti chooses to build their "Open-Top" revolvers with an arbor that is too short.
Uberti has been doing this for years. Uberti is closed for the annual national "Holiday" month at this time. You might want to re-address this issue with them next month when they reopen."
Don't know why Cimarron replied. I did contact Uberti. And the answer I received was no answer at all. My e-mail had been forwarded a few times it appears, and included was this splendid statement:

Hi Valerie,
I'm on my way to England. Uberti is closed.
Is there any way you can reply to this guy?
Thanks a million
Suzanne

I lost interest in Uberti's sub-par products some time ago; their bogus reply and "this guy" wording only furthered my distaste for their arms.

 

[M. De Land]

The sound of dribble. Now we can read it.

I notice you keep right on posting though ! So does that make you a connoisseur of dribble then ?

 

[French Colonial]

Let's not forget that Colt has lived and died by the gov't contract for its entire existence.




Then why does the subject of strength ever come up in conversations about Colt and Remington blackpowder replica guns???



Did you actually read my entire post? Miss this part?

"It's only until we get to so-called "magnum" pressures that strength becomes an issue."

Linebaugh didn't work with Colt SAA's either. Keith did and his ultimate creation was a 26,000psi .44Spl load. And we're not talking about percussion guns of 100yrs ago. In the 1930's, Colt SAA's had been proofed for smokeless and that required an improvement in the steels used and their heat treating. It also involved eliminating iron parts from the equation. The Army's request for a solid frame, for whatever reason there might've been, predated smokeless cartridges and any perceived 'need' for greater strength by 30yrs.

Let's stay in context, what "need" was there for greater strength when Colt went from the 1860 to the SAA? There was none. I illustrated this perfectly in my previous post. At that point, we were +60yrs from the .357, +80yrs from the .44Mag and +110yrs from the Linebaugh era. There is a vast chasm between percussion guns and the .500Linebaugh.

Let us also not overlook the fact that the Army's request for a .45 caliber inside lubed, centerfire cartridge also 100% necessitated a new design. Because the heeled .44Colt and Henry rimfire were the largest cartridges that would physically fit in the Open Top platform. It wasn't until Uberti enlarged the design that the .45Colt would physically fit into these guns.

People like simple answers and there isn't one. The point here is that people simply assume that they went to the solid frame because it's stronger. No evidence supports that. Quite a bit refutes it. I would wager that strength was not a consideration at all. If the solid frame was such an advantage, why would Colt submit the 1871-1872 Open Top cartridge gun to the Army at all?

The point here is that people simply assume that they went to the solid frame because it's stronger. No evidence supports that. Quite a bit refutes it.

Ok you be the first to build a 475 Linebaugh open top, we will wait

 

[45D]

Ok you be the first to build a 475 Linebaugh open top, we will wait

Why don't you? You seem to want one so bad . . .

Mike

 

[M. De Land]

Let's not forget that Colt has lived and died by the gov't contract for its entire existence.




Then why does the subject of strength ever come up in conversations about Colt and Remington blackpowder replica guns???



Did you actually read my entire post? Miss this part?

"It's only until we get to so-called "magnum" pressures that strength becomes an issue."

Linebaugh didn't work with Colt SAA's either. Keith did and his ultimate creation was a 26,000psi .44Spl load. And we're not talking about percussion guns of 100yrs ago. In the 1930's, Colt SAA's had been proofed for smokeless and that required an improvement in the steels used and their heat treating. It also involved eliminating iron parts from the equation. The Army's request for a solid frame, for whatever reason there might've been, predated smokeless cartridges and any perceived 'need' for greater strength by 30yrs.

Let's stay in context, what "need" was there for greater strength when Colt went from the 1860 to the SAA? There was none. I illustrated this perfectly in my previous post. At that point, we were +60yrs from the .357, +80yrs from the .44Mag and +110yrs from the Linebaugh era. There is a vast chasm between percussion guns and the .500Linebaugh.

Let us also not overlook the fact that the Army's request for a .45 caliber inside lubed, centerfire cartridge also 100% necessitated a new design. Because the heeled .44Colt and Henry rimfire were the largest cartridges that would physically fit in the Open Top platform. It wasn't until Uberti enlarged the design that the .45Colt would physically fit into these guns.

People like simple answers and there isn't one. The point here is that people simply assume that they went to the solid frame because it's stronger. No evidence supports that. Quite a bit refutes it. I would wager that strength was not a consideration at all. If the solid frame was such an advantage, why would Colt submit the 1871-1872 Open Top cartridge gun to the Army at all?

The whole point is that closed framed guns are stronger by design and will handle more pressure than open frame guns ! The reason they were invented is beside the point. The only reason increased pressure (magnum) of modern cartridges was introduced was to show the strength difference when both are made of the same steel alloys.
The top strap and lower frame of solid frame designs have far more mass to retain the barrel than does the open frame guns and their tiny cross section of arbor above and below the arbor slot.

 

[64Springer]

Colt was smart enough to know his guns should have been designed with a top strap.

A five year old riding a short bus could see it.

There had to be reasons. Cost and ease of manufacturing had to be a yuge consideration.

Without a top strap all machining of the receiver could be attacked from the top with no hindrances.

Less set-up time. Less tooling. Less labor deburring. Etc.

 

[Dude]

Man oh man - ten pages of back and forth over this. M De Land said that shimming the arbor is a good idea several pages back.

Yeah, they'll shoot with a short arbor, and with minimal loads or minimal shooting, will probably be fine for a long time.

Without stress testing or an engineering evaluation, it's just opinion of which looks stronger - remington or open top. 45D Seems to have proven beyond a doubt the colt is very definitely not weaker than the Remington. If you think otherwise, you must think he's lying about his research.

The point about harmonics is what settled it for me, and that's not something easily visualized. Consider this - and those of you who've worked on old cars will know this - there's a way to remove frozen head studs using harmonics. You can pull as hard as you want to loosen a frozen stud but only mangle the thing or shear it off. However, if you tap on the stud while applying turning pressure, it'll break free. And I'm not talking about strong hammer blows - just light tapping. Things will vibrate at differing frequencies, so the stud will vibrate differently than the block, eventually breaking the bond between the two.

Besides the issue of changing head space gap with depth of wedge engagement, there's the issue of harmonics hammering these parts - barrel, wedge, arbor and frame. Frankly, I want them to be LOCKED! And I mean FIRMLY! I want them behaving as one piece.

Rather than putting the time in making a gauge to judge correct wedge depth, why not spend the same amount of time and shim the arbor?

 

[M. De Land]

Colt was smart enough to know his guns should have been designed with a top strap.

A five year old riding a short bus could see it.

There had to be reasons. Cost and ease of manufacturing had to be a yuge consideration.

Without a top strap all machining of the receiver could be attacked from the top with no hindrances.

Less set-up time. Less tooling. Less labor deburring. Etc.

I think Sam realized Remington was going to run off with all his revolver business if he didn't get on the stick with the stronger design. There is no question but that the Remington 58 influenced the solid frame design in the 73 Colt revolver.
I also think the reason the Army wanted the solid frame was because early conversions were a supplement to a outdated design not made for metallic cartridge use.
The Army had already pulled one boner converting existing stocks of Springfield muskets to trapdoor breech loaders for metallic cartridge use.
I both love and shoot Trapdoor Springfields but for our Army to adopt that stop gap measure when the Rolling block rifles were available never made much sense to me.
Then they go up against the 7mm Mauser repeater in the Spanish American war with the trapdoor initially.

 

[45D]

Lets try this example to get the point across about arbor end contact, energy transfer and strength to resist separation.
Think of how a croquette mallet transfers energy when one wishes to send there opponents ball off in the weeds. He stands on his ball anchoring it solidly (wedge anchoring arbor to barrel), makes contact with his opponents ball (end fit arbor to arbor well in barrel ), and striking his own ball transfers the energy from the mallet through his ball (which remains anchored under his foot) to his opponents and sends it flying. Would the energy be transferred if his anchored ball were not touching his opponents ball ?
There is no strength added to resist separation of barrel and arbor by end contact because of the joint between them which is only linked with the wedge. Actually using the croquette example more energy to precipitate separation is transferred" by" arbor end contact !
End contact does make a good wedge depth gauge and would prevent any chance of barrel bounce to the rear if it actually happens which I doubt very much and have seen no evidence for.

Well, your example doesn't work for the setup.
Using your example for my setup, the barrel would be the ball being sent ( since that's last in the chain). Since the barrel on my setup is held tight against the arbor (ball you're hitting), you would have to put your foot on the other ball. Now hitting the first ball won't do anything to the second ball ( held by you foot). The force is transferred directly and handled as a single unit. The wedge is just there to hold the assemblies together with tension. The force is transferred directly through the arbor to the barrel assembly ( equal harmonics). If there's space between the arbor and barrel it interrupts the force and the wedge becomes a referee between to fighters.

Mike