To much is made of short arbors

[Jim in Wisconsin]

He means the force on the barrel in relation to the frame. There is no force pushing them together, just apart.

 

[45D]

He means the force on the barrel in relation to the frame. There is no force pushing them together, just apart.

Sorry, but no. What about the breech thrust, the cylinder pressure rearward against the standing breech? That equal but opposite thing from physics.

Darn physics!!!!

This is where "harmonics" comes into play. You have differing impulses happening (different rates). Two assemblies not secured solidly will work against themselves. Along with that you have a cylinder sliding back and forth.
If there's a way for the barrel assy to move rearward, it will. The answer to that is the ARBOR is in the way and will not allow it.

Again, it's a Brilliant design!!

Mike

 

[Jim in Wisconsin]

But not brilliant enough to keep Colt from dropping it to go to a solid frame.

 

[hawkeye2]

Sadly the uberti 1849 that just came in from midway is just........junk.
Doesn't index the wedge doesn't fit the cut out and once it is seated it jams the cylinder too tight to spin at all.
I nave seen some junk colt repros out of the box but this one takes the cake.
Complete waste of money.

I got a new Walker from Midway about 6 years ago and the wedge could be driven in to lock the cylinder up solid. Uberti's typical short arbor syndrome and that's what this thread is about. I don't recall any timing issues but with the barrel binding the cylinder there could have been some. The gun needed work and I had no desire to shoot it in that state.

 

[45D]

But not brilliant enough to keep Colt from dropping it to go to a solid frame.

Ha!!! The military made that decision!! Sam was dead when that decision was made.
Mason had already designed the '71'72 Open Top but the Military decided they wanted a top strap revolver.

Mike

 

[Jim in Wisconsin]

Did the U.S. Gov't buy Colt company after Sam died?

 

[Ballshooter]

if you could make head shots on squirrels at 20 yds which is highly unlikely you would be the pistol champ

I must be a pistol champ then I confirmed he was 20 yards with my leica Rangemaster hahahhah Yep, the 1851 Uberti navy is accurate! BTW I did the short arbor fix.

 

[45D]

Did the U.S. Gov't buy Colt company after Sam died?

Really?
If you want a Gov. contract, you build what they want . . .

 

[M. De Land]

Yet again sir, the rear facing side of the wedge is against the rear sections of the barrel slot. That would prevent forward movement of the barrel assembly. Since the front facing side is against the forward section of the arbor slot ( with the barrel slot being further forward), the only thing to keep the barrel assy moving to the rear would be the end of the arbor . . .
thank you . . .

Mike

I agree if it were actually moving back and forth but then the gap would be continually changing and tying up short arbor guns which I see no evidence of occurring. What is being speculated is that the barrel is bouncing off the wedge and recoiling to the rear thus closing cylinder gap without an end fit arbor to prevent it which I have never seen any evidence of occurring in any of my guns that have not been corrected.
Why would it bounce when the wedge is making contact front and back at ignition and all pressure and momentum is forward ? There simply is no gap present in a properly fit wedge or slots to precipitate a bounce! The cylinder gap may fill with fouling but it had to be present for the fouling to accumulate. If the gap is set at .0025-.003 gap as some say then there is precious little space for any fore and aft movement especially after the first shot fouling is laid down.
I will check this with a feeler gauge next time out but I doubt that this speculation is actually happening as I have had them with .010 gap and none of them have ever been tied up from rearward contact of the barrel.

Darn physics!!!!

This is where "harmonics" comes into play. You have differing impulses happening (different rates). Two assemblies not secured solidly will work against themselves. Along with that you have a cylinder sliding back and forth.
If there's a way for the barrel assy to move rearward, it will. The answer to that is the ARBOR is in the way and will not allow it.

Again, it's a Brilliant design!!

Mike

I doubt very much if that actually occurs but is worth a look see. I'll check that fore and aft barrel motion notion with a feeler gauge next time out ! I would think it would cause a cylinder tie up metal to metal ( barrel against cylinder) and I have never had that occur.

 

[Jim in Wisconsin]

"If you want a Gov't contract, you build what they want"
That's for sure. The question would be - do you want a gov"t contract. Lots of companies have decided it wasn't worth the trouble. They could have stuck with their old design if they really thought it was better. Winchester didn't need the govt to survive.
Why did the U.S. army want solid frames anyway? Were they just stupid?
The decision to go with a solid frame was made by the owners of Colt, not by the government.

 

[Relic shooter]

My vote is to close this thread before some start posting photos of their arbors behind the woodshed

 

[NorthFork]

Sadly the uberti 1849 that just came in from midway is just........junk.
Doesn't index the wedge doesn't fit the cut out and once it is seated it jams the cylinder too tight to spin at all.
I nave seen some junk colt repros out of the box but this one takes the cake.
Complete waste of money.

Yup! I agree.

 

[NorthFork]

Really?
If you want a Gov. contract, you build what they want . . .

Yup!

 

[64Springer]

My vote is to close this thread before some start posting photos of their arbors behind the woodshed

You know what they say about arbors.

Some arbors are longer than others.

Or is it spears?

I forgets.

 

[NorthFork]

@45D

There is a saying that is as old as the Bible- "none so blind as those who will not see". That applies to a certain forum member here that is not you or me, you know who I'm referring to.

 

[45D]

I agree if it were actually moving back and forth but then the gap would be continually changing and tying up short arbor guns which I see no evidence of occurring. What is being speculated is that the barrel is bouncing off the wedge and recoiling to the rear thus closing cylinder gap without an end fit arbor to prevent it which I have never seen any evidence of occurring in any of my guns that have not been corrected.
Why would it bounce when the wedge is making contact front and back at ignition and all pressure and momentum is forward ? There simply is no gap present in a properly fit wedge or slots to precipitate a bounce! The cylinder gap may fill with fouling but it had to be present for the fouling to accumulate. If the gap is set at .0025-.003 gap as some say then there is precious little space for any fore and aft movement especially after the first shot fouling is laid down.
I will check this with a feeler gauge next time out but I doubt that this speculation is actually happening as I have had them with .010 gap and none of them have ever been tied up from rearward contact of the barrel.

Ok, so why wouldn't they move back and forth? You know, physics . . . action - reaction. You always point out the butt joint is going move. What would the reaction be if that happens? Barrel pivots backwards . . . You're exactly right with your speculation about the arbor stopping that action. So the wedge will arrest forward movement, the arbor arrests rearward movement = no damage to the wedge . . . it's all linear.

The wedge only contacts the barrel assy at the rear of the slot. The foreword side of the wedge contacts the forward side of the arbor slot - which means the end of the arbor is the only thing stopping rearward barrel movement ( if set up correctly) otherwise it would be a combination of up/down clearance between arbor and arbor hole and the wedge getting battered. That's how Walker wedges get "joggles" in them.
.0025" - .003" "Gaps" /endshake is what I set them up at. The factory doesn't "set" it at any spec. and using a feeler gauge doesn't either as the wedge can move during the shooting session. It's not a setting if there's nothing to keep it "set".

I doubt very much if that actually occurs but is worth a look see. I'll check that fore and aft barrel motion notion with a feeler gauge next time out ! I would think it would cause a cylinder tie up metal to metal ( barrel against cylinder) and I have never had that occur.

I doubt you'll be fast enough to measure it by the time the vibration is over. They don't stay put in one direction or the other.

Mike

 

[45D]

Did the U.S. Gov't buy Colt company after Sam died?

You must be younger than I figured . . .

 

[45D]

"If you want a Gov't contract, you build what they want"
That's for sure. The question would be - do you want a gov"t contract. Lots of companies have decided it wasn't worth the trouble. They could have stuck with their old design if they really thought it was better. Winchester didn't need the govt to survive.
Why did the U.S. army want solid frames anyway? Were they just stupid?
The decision to go with a solid frame was made by the owners of Colt, not by the government.

That's a brainless question . . . It's pretty much history now. Obviously Colt wanted a gov. contract so they built what the government ask for !! Maybe you should have been there to tell them what they should have done. Like I said, they already had a new cartridge revolver - '71/'72 Open Top.

You're wrong, the decision was the Military not Colt. You could probably do a search and learn a little bit about this subject. It's a pretty well known deal.
Why would the Military want what it asked for ? Cheaper. It's easier to manufacture a frame with a screw in barrel. The same reason Top strap revolvers are still made today.

Mike

 

[M. De Land]

I must be a pistol champ then I confirmed he was 20 yards with my leica Rangemaster hahahhah Yep, the 1851 Uberti navy is accurate! BTW I did the short arbor fix.

Was it accurate before the arbor fit job?

 

[M. De Land]

Ok, so why wouldn't they move back and forth? You know, physics . . . action - reaction. You always point out the butt joint is going move. What would the reaction be if that happens? Barrel pivots backwards . . . You're exactly right with your speculation about the arbor stopping that action. So the wedge will arrest forward movement, the arbor arrests rearward movement = no damage to the wedge . . . it's all linear.

The wedge only contacts the barrel assy at the rear of the slot. The foreword side of the wedge contacts the forward side of the arbor slot - which means the end of the arbor is the only thing stopping rearward barrel movement ( if set up correctly) otherwise it would be a combination of up/down clearance between arbor and arbor hole and the wedge getting battered. That's how Walker wedges get "joggles" in them.
.0025" - .003" "Gaps" /endshake is what I set them up at. The factory doesn't "set" it at any spec. and using a feeler gauge doesn't either as the wedge can move during the shooting session. It's not a setting if there's nothing to keep it "set".


I doubt you'll be fast enough to measure it by the time the vibration is over. They don't stay put in one direction or the other.

Mike

I know the open frame guns flex but I have never seen any evidence that the barrel moves rearward off the wedge !
Harmonics is linear barrel oscillation not fore and aft movement !
If the barrel was moving as speculated then all Uberti's and 30 years of Pietta open frame guns would be self destructing and this is not and has not occurred.
Should they be end fit and is it a good mod ........I have always said yes but is it necessary for the guns to be accurate and reliable................ I have to say no it isn't .