Ruger Old Army

Muzzleloading Forum

Help Support Muzzleloading Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
So.......

I am still waiting to see the open top even "beefed up" that handles magnum loads from Casull or Linebaugh, until then.....
The open frame is weaker for the same reason a single bolt lug is weaker in center fire rifles, Single sided off set support does not handle pressure as well as opposite two side support with less steel ( arbor with a wedge slot cut in the middle of it) to withstand the thrust pressure. The steel left on either side of the wedge slot in the arbor is far less than is the combined mass of the top strap and lower frame along with it being off set to the thrust vector pressure line.
Think Krag (one lock lug to the rear) as opposed to Springfield ( two lock lugs on opposite sides to the front) bolt guns.
Front lug lock up handles pressure better and flexes the action less than does rear lug lock up support.
The same is true of closed frame design in revolvers.
There is not one magnum level revolver I'm aware of that uses an open frame design and the reason is thrust pressure management.
 
It's funny the "bug" in your head about "Ruger only " loads being the determining factor for an open-top platform being capable and in some instances being stronger than the top strap equivalent. I've never said anything about them shooting Ruger Only loads ( but I am heading in that direction and they are fine!! Which means, I've already proven my point!).
The 2 sides of the wedge slot doesn't matter a whit as long as the "end fit " is correct and tight . . . that's a main factor in why I can already shoot what I'm shooting. Your understanding of the platform is sorely lacking . . .

Mike
Actually the opposite is the reality !
 
What do you figure it would take for an open top to handle magnum loads? How much beefier the arbor? Of course the cylinder would need to be enlarged to fit a larger arbor. How much more metal in the frame? The wedge probably would be fine as is.
 
What do you figure it would take for an open top to handle magnum loads? How much beefier the arbor? Of course the cylinder would need to be enlarged to fit a larger arbor. How much more metal in the frame? The wedge probably would be fine as is.
A mechanical engineer trained in metallurgy could calculate the stress requirements and added steel mass needed for equivalent strength in an open frame design just as they can in bridges, buildings and airplanes. Open frames simply are not as an efficient or strong design as closed frames are to handle the stress requirements evolved and is the main reason for the evolution of design..
 
What do you figure it would take for an open top to handle magnum loads? How much beefier the arbor? Of course the cylinder would need to be enlarged to fit a larger arbor. How much more metal in the frame? The wedge probably would be fine as is.

Well honestly (fortunately), the calibers we have available for these are what they are (45C/45acp) and there isn't a named "magnum" loading for them. There IS a +p load for both though. In some instances the "mag" load is double the tier1 load and some are as much as 3 times!
So, you can judge the name for yourself by the pressures involved.
45C tier1 tops out at 14K psi . The 45C +p is almost 1000 psi more at 23K psi . That's a pretty good step towards "magnum" and is the "entry level" for so called "Ruger only" loads. My Dragoons handle this very well.
The 45acp runs around 20K psi and the +p is 23K, so not as big a jump but the SAME as the 45C +p.

Personally, I think the 45acp '60 Army (U) built correctly and within my specs is great at the +p loading and it has proven to be a very accurate setup.

The 45C Dragoons, built accordingly, are excellent with +p's and the setup can probably go quite a bit further. We'll find out !!

The "where I am" with testing these particular loads in these open top revolvers (including customers and others I'm acquainted with) is irrefutable proof that the platform can perform, with excellent results, as well and even better than many top strap revolvers no matter what anyone else says. You prove it at the firing line, not behind a keyboard with biased opinion.

Mike
 
Last edited:
Without any engineering background, Sam Colt designed a revolutionary pistol that withstood the forces subjected to it. I'm not saying it's not necessary for an engineer to calculate the forces as in building a bridge or an airplane, but the pioneers usually figured out a way without the formal training. The Wright Brothers only had practical experience with bicycles, taking the leap from there. I recall a statement made by a renowned engineer (no longer remember who) that went something like - "if it looks right, it probably is". Of course, you can look at the opposite side of that coin and laugh about the goofy 'flying' machines that came before the Wright's successful contraption. Maybe they looked 'right' to their creators? But in the realm of engineering, a lot of times it's possible to visualize the forces and get a 'feel' for whether it's right or not. I'm thinking it wouldn't take a whole lot more beefing up to create an open top that would safely handle magnum loads. Maybe it wouldn't take any more than a Walker or dragoon size gun to accomplish that. Or perhaps a Walker size with a larger arbor and slightly larger frame? Making a cylinder to handle the forces wouldn't be a problem, so the issue is whether the rest of the gun would hold together.

You know, the Walker was the most powerful revolver till the 357 magnum - so that says something right there about its strength.
 
Without any engineering background, Sam Colt designed a revolutionary pistol that withstood the forces subjected to it. I'm not saying it's not necessary for an engineer to calculate the forces as in building a bridge or an airplane, but the pioneers usually figured out a way without the formal training. The Wright Brothers only had practical experience with bicycles, taking the leap from there. I recall a statement made by a renowned engineer (no longer remember who) that went something like - "if it looks right, it probably is". Of course, you can look at the opposite side of that coin and laugh about the goofy 'flying' machines that came before the Wright's successful contraption. Maybe they looked 'right' to their creators? But in the realm of engineering, a lot of times it's possible to visualize the forces and get a 'feel' for whether it's right or not. I'm thinking it wouldn't take a whole lot more beefing up to create an open top that would safely handle magnum loads. Maybe it wouldn't take any more than a Walker or dragoon size gun to accomplish that. Or perhaps a Walker size with a larger arbor and slightly larger frame? Making a cylinder to handle the forces wouldn't be a problem, so the issue is whether the rest of the gun would hold together.

You know, the Walker was the most powerful revolver till the 357 magnum - so that says something right there about its strength.
Materials and heat treating come into play as well.
 
Well honestly (fortunately), the calibers we have available for these are what they are (45C/45acp) and there isn't a named "magnum" loading for them. There IS a +p load for both though. In some instances the "mag" load is double the tier1 load and some are as much as 3 times!
So, you can judge the name for yourself by the pressures involved.
45C tier1 tops out at 14K psi . The 45C +p is almost 1000 psi more at 23K psi . That's a pretty good step towards "magnum" and is the "entry level" for so called "Ruger only" loads. My Dragoons handle this very well.
So you're saying a 44Mag generates pressures of 28K psi, and possibly even as high as 42K psi? 😳

That's scary

Which are you shooting, Mike - 45acp +p or the 45 Colt +p?
 
So you're saying a 44Mag generates pressures of 28K psi, and possibly even as high as 42K psi? 😳

That's scary

Which are you shooting, Mike - 45acp +p or the 45 Colt +p?

1860 Army - 45acp +'s
Dragoons - 45C +'s

The revolvers must be set up with a reinstalled /torqued arbor with correct arbor length that allows. 0015" - .0025" endshake Max. Wedge must be in tight. An 11° forcing cone cut is a must! I use Kirst conversion cylinders and no other. Kirst doesn't recommend this ammo and I am NOT affiliated with Kirst in any way. I don't recommend this setup unless I personally have set the revolver up. All of this info is for informational use only.
 
Last edited:
So you're saying a 44Mag generates pressures of 28K psi, and possibly even as high as 42K psi? 😳

That's scary

Which are you shooting, Mike - 45acp +p or the 45 Colt +p?
Colts open frame design is and was perfectly adequate for black powder stress levels but became inadequate when the pressure and velocity levels of semi smokeless and smokeless powder was invented and became widely used.
The design also flexes more than does solid frame construction and is another reason for the design evolution to more rigid platforms..
 
Last edited:
I’m not sure how this fits into y’all’s conversation here, and I’m sure some of you have heard of this:

https://en.m.wikipedia.org/wiki/.45_Black_Powder_Magnum
Good read and I had not previously heard of the BPM cartridge.
A few years ago I re-barreled and chambered a Martini Cadet I was making for a gong rifle in .357 Maximum for the very same volume increase reason with the idea of shooting black powder in it.
Never have gotten around to shooting the BP loads as it works so well with smokeless.
Since I've made another Cadet in .357 Mag that does the same as the Maximum cartridge with less powder so now I have no reason not to get off my butt and test out the BP potential of the maximum case. It should prove to be and interesting experiment !
I surely love Black Powder, smell, smoke and sound !
 
45D: Thank you for the details. I was getting ready to do my pencil and paper spreadsheet to see the relationships.

As noted previously, in a move of stupidity in not checking the charge I did a double load of Unique (14-15 grains) in the 47 Walker with a 45C Unmentionble (I went with the Howell as no work needed s). You sure could tell! It took it like a trooper, not that I want to repeat that.

The Wright Brothers only had practical experience with bicycles, taking the leap from there.

The Wright brothers were unusual. Clearly extraordinarily smart as they built a wind tunnel to test their ideas and they built the engine for the Aircraft. The got enough correct to have a flyable machine.

They also had a design that did not stand the test of time. Having the Tail First was wrong (latter Canard came back in but only some rare Rutan and some fighter designs now).

Wing Warping (literally twisting the wing) worked. This gets fuzzy, but Curtis in trying to break the patent came out with Ailerons and those are still prime today though you can add in flaparons and spoilers on passenger jets.

I think Ailerons would have come, wing warping was seriously limited to slow speed aircraft with not much load.

Eddison brute forced inventions with an idea and then teams of people trying various solutions until they got something that worked.

I don't know how Colt came up with his design. Get into the background and it tended to be an inspiration from something done before with a take not done before (inutitive?) . Maybe Tesla like. He certainly was pushing the far edge of materials.

If the reports are correct, there were issues in Colts first work so not a slam dunk but the refinement proceeded and a 47 Walker was pushing a boundary betweeen a Muzzle Loader Carbine and a multi shot.
 
Everyone please understand, just because a SA revolver has a TOP STRAP, doesn't mean it can safely shoot 454 Casull ammo!!! It most certainly CANNOT!!! Some on this forum seem to think that the TOP STRAP is THE definitive answer to pressures one may introduce to a particular setup. It is in fact not true!! The TOP STRAP design has been universally adapted because of the ease of production and cost effectiveness, not because of ability!! The ONLY way a SA revolver can handle any of the modern "TOP Tier" ammo is because of materials used and an INCREASE in the thickness and width of the TOP STRAP!!!
That said, I have proven many times that a correctly setup open-top platform can easily surpass MANY "top strap" revolvers and the testing goes on . . .

Mike
This thinking is patently absurd and provably false ! Open frame design will never be able to handle thrust pressure as efficiently as closed frame design ! If it were superior or even equivalent then open frame Magnum level revolvers would be produced.
Even with the advance of alloys and heat treating the design is obsolete and inadequate for magnum level pressure dynamics.
 
This thinking is patently absurd and provably false ! Open frame design will never be able to handle thrust pressure as efficiently as closed frame design ! If it were superior or even equivalent then open frame Magnum level revolvers would be produced.
Even with the advance of alloys and heat treating the design is obsolete and inadequate for magnum level pressure dynamics.
How can you say that when 45D claims he's shooting 45C +p ammo through his open tops? We don't know what sort of accuracy he's getting so he'll have to fill in that blank. But he's said they're not coming apart and show no sign of wear.

Since you say it can't be done, if I was a machinist, I'd take up the challenge. I'm mostly curious what it would take to pull that off.
 
How can you say that when 45D claims he's shooting 45C +p ammo through his open tops? We don't know what sort of accuracy he's getting so he'll have to fill in that blank. But he's said they're not coming apart and show no sign of wear.

Since you say it can't be done, if I was a machinist, I'd take up the challenge. I'm mostly curious what it would take to pull that off.
Mike has refuted his claims and proven what he (45D) has said on here many many times but you can't make an irrational person rational anymore than you can force a horse to drink.
 
I would say that puts 45D in the same category as Colt, Wright Brothers and Tesla!

As this is ROA, I will interject a query that I may well have missed. I know its not recommended (ah hem) but with an unmentionalbe cylinder how high a CUP pressure would the ROA be rated for?

Now I have not asked that thoughtlessly. As its derived from the Blackhawk (not a clean sheet design) its going to share some of the capability aka 44 magnum. In looking at a picture it appears the top strap of a cartridge Blackhawk is a lot thicker than an ROA.

I had one back in the 70s (sadly a transfer bar model, great gun, hated the transfer bar). In one of those stupid things you can do, I was reloading 44 mag with a Lee Pound it in loader and I believe I had a blank. In all cases I have done that same stupid thing since, the bullet went into the barrel far enough that you could rotate the cylinder.

I then not thinking, pulled the hammer back and fired, this time with a full up rounds. I realized what that meant, barrel was fine (no bulge) and it was equally accurate after or better than any of the S&W I owned since.

If I had been thinking I would have tested a primer only to see if the bullet did seat. I have had that happen since but

So, not something you begin to want to test with a shot following but also amazing it did not go boom let alone no barrel damage.
 
Back
Top