Milling out 1860 Pietta inserts for a Ransom Rest

[45D]

Truth is I could both make and fit a brand new arbor from tool steel if I wanted just as I have the wedge and trigger but it would be a lot of unnecessary work most likely. This experiment has been an itch I've been wanted to scratch any way for some time. I just thought it would be fun to find out about the supposed short arbor deficit ( if I can) and bring the rest of you folks that may have interest along for the ride.

Well oddly enough, that "supposed " short arbor has been known about for a long time along with the problems it brings and the "fix" has proven to be the cure whether any one person agrees or doesn't.

Fact is, the open tops that I own started off with destructive behaviors and since the "fix", there hasn't been an issue whatsoever. Basically, your "experiment " has been observed in reverse by thousands of folks. So, you're a little late to the parry.

Mike

 

[M. De Land]

Mike, when you have been around guns and gun work for as long as I have been one hears a lot of "fact" that turns out to be so much apple sauce based on opinion and hear say. Some of it is good stuff and can be relied upon others , not so much. Than too, there is very often more than one way to approach and achieve the same goal. "My way or the highway thinking" doesn't work for me because I have seen it fail to be the absolute it was billed , to often. "If" the thinking proves to be irrefutably true I will except and utilize the idea but never the attitude.
As you have probably ascertained by now I want to find out personally if my thinking on this subject is accurate or not hence the effort. It is only a one gun test which means it is not definitive but should give a pretty fair idea about it. You have said several things my experience and learned knowledge does not square with so pardon me if I don't automatically dump all my thinking and line up with yours.

 

[Bad Karma]

Yeah, that would work too! I always prefer simple if it works best. I think I will still go with the shim and machined solid plug idea as washers seldom are precise in their thickness and for this experiment I think I need as much precision as I can muster to weed out variables.

When I used them I faced them to exact thicknesses as needed. Painful bit…

 

[M. De Land]

When I used them I faced them to exact thicknesses as needed. Painful bit…

Good thinking!

 

[Ed C.]

Yep, you never know when you'll want to go back to "broken" after you fix it . . .

Mike

Or when your "fix" may need a little fine tuning. For those of us with limited experience sometimes a little trial and error is necessary.

 

[45D]

Or when your "fix" may need a little fine tuning. For those of us with limited experience sometimes a little trial and error is necessary.

Ed, most definitely!! It's a "fit till it's right" kinda thing. When fitting the spacer, you first have to get contact at the frame /barrel lug and then "adjust" it to close in on the endshake spec. you want (Mine is .0025" - .003" cap gun, .0015" - .002" max for "unmentionables") making sure the wedge has a LOT of tension (meaning you have to really smack it with a plastic face hammer to remove it!!)

What I meant by my post about being able to remove the spacer was after you're done fitting, why would you want to remove it ? I've had some folks say they wouldn't want to make the fix permanent so they could return it back to original condition . . . original " broken " condition? WHY?!! Lol!!!

It sounds like quite a challenge that Mr.D.Land wants to end up with the wedge in the exact same position with and without the spacer in place!! In one instance, there will be minimal tension , and with the spacer there should be considerable tension (if not, there's not much reason for the experiment).
Hint, maybe going for the same endshake with both (one "measured", one "defined)" would be a little easier? (Wedge depth won't matter with the spacer in.)

Mike

 

[Rich44]

What I meant by my post about being able to remove the spacer was after you're done fitting, why would you want to remove it ? I've had some folks say they wouldn't want to make the fix permanent so they could return it back to original condition . . . original " broken " condition? WHY?!! Lol!!!

I agree, but you said "after you're done fitting". During the fitting process it might be helpful if a easy way of removal was provided just in case. You seem to be the type that wants to spend an hour saying why it is not needed, instead of just taking 15 min and doing it. What is hard to believe is you have the knowledge to understand that a correct length arbor is really from a mechanical viewpoint the only proper answer for the correct working, but dropping something down a blind hole without insuring you can get it out is OK. Again from a mechanical stand point it is just a good practice to cover your bases. Maybe not positively needed in this occasion, but it is developing you work skills and habits so you don't have to say on the next job, "Now how am I going to get that out"? Or worse yet the Boss saying that was stupid. As a tool maker setups and procedures are very important.

 

[45D]

I agree, but you said "after you're done fitting". During the fitting process it might be helpful if a easy way of removal was provided just in case. You seem to be the type that wants to spend an hour saying why it is not needed, instead of just taking 15 min and doing it. What is hard to believe is you have the knowledge to understand that a correct length arbor is really from a mechanical viewpoint the only proper answer for the correct working, but dropping something down a blind hole without insuring you can get it out is OK. Again from a mechanical stand point it is just a good practice to cover your bases. Maybe not positively needed in this occasion, but it is developing you work skills and habits so you don't have to say on the next job, "Now how am I going to get that out"? Or worse yet the Boss saying that was stupid. As a tool maker setups and procedures are very important.

You're right, maybe I wasn't clear. The spacer I use can be dropped in and easily falls out while I'm fitting (adjusting the thickness). But I meant when that's all done, I mount it permanently in place so it won't be lost accidentally. Sorry for the confusion.
(and you're right, it's about a ten minute operation)

Since you seem to understand this, what I do allows me to get to a .004" - .005" endshake quickly and then I "zero in" (fine tune) on my end spec by dressing the end of the arbor 1 to 2 thousandths. Doing it that way opens the slot slightly but that is corrected by the wedge bearing which also gives "placement" (depth) options.

Mike

 

[Ed C.]

Ed, most definitely!! It's a "fit till it's right" kinda thing. When fitting the spacer, you first have to get contact at the frame /barrel lug and then "adjust" it to close in on the endshake spec. you want (Mine is .0025" - .003" cap gun, .0015" - .002" max for "unmentionables") making sure the wedge has a LOT of tension (meaning you have to really smack it with a plastic face hammer to remove it!!)

What I meant by my post about being able to remove the spacer was after you're done fitting, why would you want to remove it ? I've had some folks say they wouldn't want to make the fix permanent so they could return it back to original condition . . . original " broken " condition? WHY?!! Lol!!!

It sounds like quite a challenge that Mr.D.Land wants to end up with the wedge in the exact same position with and without the spacer in place!! In one instance, there will be minimal tension , and with the spacer there should be considerable tension (if not, there's not much reason for the experiment).
Hint, maybe going for the same endshake with both (one "measured", one "defined)" would be a little easier? (Wedge depth won't matter with the spacer in.)

Mike

Agree. The wedge will not seat in the same place using a given amount of force with and without an arbor spacer. Once the set up is made the wedge should seat in the same place.

 

[M. De Land]

I agree, but you said "after you're done fitting". During the fitting process it might be helpful if a easy way of removal was provided just in case. You seem to be the type that wants to spend an hour saying why it is not needed, instead of just taking 15 min and doing it. What is hard to believe is you have the knowledge to understand that a correct length arbor is really from a mechanical viewpoint the only proper answer for the correct working, but dropping something down a blind hole without insuring you can get it out is OK. Again from a mechanical stand point it is just a good practice to cover your bases. Maybe not positively needed in this occasion, but it is developing you work skills and habits so you don't have to say on the next job, "Now how am I going to get that out"? Or worse yet the Boss saying that was stupid. As a tool maker setups and procedures are very important.

Consistent wedge depth is easily accomplished with a feeler gauge in the barrel cylinder gap or a simple hand build gauge that fits the under ledge of the wedge head against the barrel in short arbor guns. Also, remember mention of the wedge thickness being just as important as the angular width ? I don't believe keys were designed to be driven into the slots until they "smoke" from compression. A bump from a screw driver handle has always kept mine in place and made them easily removable.
The end fit arbor does make key depth easier to re-establish each time an is a plus I agree with .

 

[45D]

Still not a clue . . .

This experiment is done . . .
Mike

 

[M. De Land]

Still not a clue . . .

This experiment is done . . .
Mike

How do you figure that, my thread, my gun and my experiment ? You seem to be worried that the gun may prove to be accurate with a short arbor and may not blow the barrel off! Then again it may prove your theories correct and if true we will all be the better off for it. I don't see how any of us can loose if we learn something useful.
Sure is odd how so many of us have been shooting these short arbor Pietta's for years and never realized they were inaccurate and liable to blow the barrel off at any moment.

 

[45D]

Well, they aren't my "theories", it's the Colt design. You tend to think the Italians make Colt style revolvers better than Colt. They don't.
My point was made after your explanation of the all important wedge thickness blah blah . . . you can't seem to understand that the depth of the wedge means zilch if the arbor is bottoming out. After the clearance is removed with the wedge installed (under tension) it doesn't matter how much more you drive the wedge in, it won't change the endshake !! . . . which is the whole point!!
So, if you're not going to impart any tension on the Union of the 2 assemblies when the spacer is installed, why bother with continuing your experiment? In other words, if you're not going to do it right, why bother?
A loose fit wedge with or without a spacer makes no difference. It's not the " presence " of a spacer that counts . . . it's the actual use of the spacer taking up space and being under tension (because the wedge is PULLING the BARREL assembly AGAINST the end of the arbor!! Why is that so hard to understand?

Mike

 

[Rich44]

Well in my life time I have done many experiments. Think it is fun and have always learned, but some can stay a secret because a lack of common sense that was used and I wound up just being lucky. Bet some of our best inventors learned from failure. So I do enjoy some one posting about a test they wish to do and the results. It can keep me out of trouble.

So De land please continue with your testing, I would be interested in your findings. Now I should leave it there but the reality side of me says I should explain my opinion even through this subject matter gets a lot of conflicting talk with people standing firm.

You plan on using a Ransom Rest as part of your experiment, never had one, but I can see they are nice. They are expensive and are precision made and must return to the exact same position for them to give useful results. When they are returned to firing position they must be exact as possible. And you are spending the proper time to insure the grip panels will not give problems with movement. This is all good work that would be required to make for a fair test. But why have you not let the same mechanical requirements for the Ransom Rest rub off on the arbor requirements on a Revolver? Run of the mill bp revolvers are production guns. Meaning they sometimes can be improved. And that would include the arbor length to see if it is correct length and gives the proper metal to metal contact to insure your preferred cylinder gap.

No matter what method of correcting either by washers, spacer, screw, or increasing length of arbor is used the result is to give a solid stop to insure proper spacing of cylinder with a tap fit of the wedge. Many of the people here like Mike have took the effort to insure no matter how many times he takes his colt apart it will return to the same setting. Not dependent on wedge position but simply metal to metal contact. And after seeing the results have a hard time understanding why a person would want to make their revolver any different. I do realize that some/maybe most do not want to get this involved and just want to have fun shooting. Or maybe do not have the tools. But some including me wish to have their colt working like a precision machine. And would question why you are using a Ransom Rest that uses a positive stop to test if the mechanics of a revolver should have a positive stop also? Just can sound a little funny.

 

[Festus]

How do you figure that, my thread, my gun and my experiment ? You seem to be worried that the gun may prove to be accurate with a short arbor and may not blow the barrel off! Then again it may prove your theories correct and if true we will all be the better off for it. I don't see how any of us can loose if we learn something useful.
Sure is odd how so many of us have been shooting these short arbor Pietta's for years and never realized they were inaccurate and liable to blow the barrel off at any moment.

Never had a short arbor Pietta. Had to fix all my Ubertis though.

 

[45D]

Never had a short arbor Pietta. Had to fix all my Ubertis though.

Festus, Pietta corrected their arbor length around 2010/2012 so all earlier Pietta's are just like all other reproductions . . . short.

Mike

 

[Bad Karma]

 

[M. De Land]

Well in my life time I have done many experiments. Think it is fun and have always learned, but some can stay a secret because a lack of common sense that was used and I wound up just being lucky. Bet some of our best inventors learned from failure. So I do enjoy some one posting about a test they wish to do and the results. It can keep me out of trouble.

So De land please continue with your testing, I would be interested in your findings. Now I should leave it there but the reality side of me says I should explain my opinion even through this subject matter gets a lot of conflicting talk with people standing firm.

You plan on using a Ransom Rest as part of your experiment, never had one, but I can see they are nice. They are expensive and are precision made and must return to the exact same position for them to give useful results. When they are returned to firing position they must be exact as possible. And you are spending the proper time to insure the grip panels will not give problems with movement. This is all good work that would be required to make for a fair test. But why have you not let the same mechanical requirements for the Ransom Rest rub off on the arbor requirements on a Revolver? Run of the mill bp revolvers are production guns. Meaning they sometimes can be improved. And that would include the arbor length to see if it is correct length and gives the proper metal to metal contact to insure your preferred cylinder gap.

No matter what method of correcting either by washers, spacer, screw, or increasing length of arbor is used the result is to give a solid stop to insure proper spacing of cylinder with a tap fit of the wedge. Many of the people here like Mike have took the effort to insure no matter how many times he takes his colt apart it will return to the same setting. Not dependent on wedge position but simply metal to metal contact. And after seeing the results have a hard time understanding why a person would want to make their revolver any different. I do realize that some/maybe most do not want to get this involved and just want to have fun shooting. Or maybe do not have the tools. But some including me wish to have their colt working like a precision machine. And would question why you are using a Ransom Rest that uses a positive stop to test if the mechanics of a revolver should have a positive stop also? Just can sound a little funny.

Well in my life time I have done many experiments. Think it is fun and have always learned, but some can stay a secret because a lack of common sense that was used and I wound up just being lucky. Bet some of our best inventors learned from failure. So I do enjoy some one posting about a test they wish to do and the results. It can keep me out of trouble.

So De land please continue with your testing, I would be interested in your findings. Now I should leave it there but the reality side of me says I should explain my opinion even through this subject matter gets a lot of conflicting talk with people standing firm.

You plan on using a Ransom Rest as part of your experiment, never had one, but I can see they are nice. They are expensive and are precision made and must return to the exact same position for them to give useful results. When they are returned to firing position they must be exact as possible. And you are spending the proper time to insure the grip panels will not give problems with movement. This is all good work that would be required to make for a fair test. But why have you not let the same mechanical requirements for the Ransom Rest rub off on the arbor requirements on a Revolver? Run of the mill bp revolvers are production guns. Meaning they sometimes can be improved. And that would include the arbor length to see if it is correct length and gives the proper metal to metal contact to insure your preferred cylinder gap.

No matter what method of correcting either by washers, spacer, screw, or increasing length of arbor is used the result is to give a solid stop to insure proper spacing of cylinder with a tap fit of the wedge. Many of the people here like Mike have took the effort to insure no matter how many times he takes his colt apart it will return to the same setting. Not dependent on wedge position but simply metal to metal contact. And after seeing the results have a hard time understanding why a person would want to make their revolver any different. I do realize that some/maybe most do not want to get this involved and just want to have fun shooting. Or maybe do not have the tools. But some including me wish to have their colt working like a precision machine. And would question why you are using a Ransom Rest that uses a positive stop to test if the mechanics of a revolver should have a positive stop also? Just can sound a little funny.

Pardon me for a slow reply as I got my left hand into a table saw yesterday on the job and rearranged the end of my middle finger and thumb ( read cut it off but for a piece of skin) . I'm pecking out a reply to your question one handed.
Any way, I have a 1860 short arbor Pietta that was as or more accurate than my solid frame guns, all of which have as much tuning done to them. I honestly saw no reason to fit the arbor end from the way it performed. So when I hear a theory I know experiential-ly is not universally true,
I will say what I think.
This experiment with the Ransom rest should reveal the truth about what I think I know at this point in my never ending search for what is true or not.
I have used this very same rest to test a new match barrel I fit to my 1911 Colt and it delivered a five shot 25 yard group that went .900. I'm confident if I can get the

 

[M. De Land]

Sorry about being slow answering your question as I had a small set back (could have been a lot worse) on the job Thursday involving a table saw and two digits on the left hand which will set back this experiment a while. They sewed the middle finger back on and looks like we can save it. Cut a plug of meat out of the thumb but didn't get the bone.
Any way the reason I never felt the need to fit the arbor end to the well bottom is because my short arbor Pieta shot as well or better ( over bench and sand bags) than my tuned solid frame guns that I was winning matches with. It did need a new trigger and wedge because both were to soft from the factory and deformed over some years of use. The new parts made of tool steel solved the problem thus far without change. I went with a new bolt/trigger flat spring made from a stainless steel flat/coil spring taken out of a broken Luftkin measuring tape which worked perfectly , are indestructible and have a faster response time then does wire/coil/lever springs.
I tend to go with things I can see actually working and the (if it ain't broke) idea in mind.

 

[Rich44]

Sorry about your accident. Those things can happen in a split second with shop tools for sure. Like you said could have been worse very easily. Hope you heal up soon, stay safe.