Fix for Tight Arbor/Barrel Fit on Piata Paterson, Right Track?

[ThreeCrows]

I have a Piata Paterson with a extremely tight arbor to barrel fit. As the Piata Paterson doesn't have a loading lever to aid in pushing the barrel off the arbor and there is really no good place to tap the barrel off it is a problem. I searched the forums and this usually has fixes for loose arbors or wedges. I was thinking of using a small automobile brake cylinder hone and running it into the arbor hole in the barrel but I have had no luck finding a hone. I guess with most cars having disc brakes there is no need for hones of this type. So am I on the right track or does anyone have a better way of fixing this?

Thanks for any help,
ThreeCrows

 

[Brokenbear]

I have a Piata Paterson with a extremely tight arbor to barrel fit. As the Piata Paterson doesn't have a loading lever to aid in pushing the barrel off the arbor and there is really no good place to tap the barrel off it is a problem. I searched the forums and this usually has fixes for loose arbors or wedges. I was thinking of using a small automobile brake cylinder hone and running it into the arbor hole in the barrel but I have had no luck finding a hone. I guess with most cars having disc brakes there is no need for hones of this type. So am I on the right track or does anyone have a better way of fixing this?

Thanks for any help,
ThreeCrows

I would have to say taking a brake hone to you shooter might be a bit overkill ..In the service we would get a a new weapon that had to run flawlessly because of our missions ...we would get graphite grease and coat the moving parts and then work the action (cycle) however long it took to get it absolutely silk smooth and dependable ..then mate flawless magazines and code them to the weapon ..

If this doesn't appeal to you then get some 0000 steel wool and unwind a pad of it and tear it into 2" wide strips (Lengthwise) ..it will be about 20" long ...fold in half and wrap around your arbor one full wrap and then "saw" it back and forth up and down the arbor

Then get an appropriate diameter dowel rod (6-8") saw a slit in one end and start a new strip of 0000 in it and wrap it around the dowel for a tight it in your cylinder arbor hole ..place in you drill and polish it up
You may not have to do much to either the arbor or pilot hole as oxidation alone could easily cause what you are experiencing

Have a great week to all
Bear

 

[hawkeye2]

Look at the slot in the arbor for the wedge, I've found problems there on a few occasions. Take a stone and holding it vertically dress each edge of the slot, both at the same time to remove any burrs. Check the arbor for dings that may have displaced metal upward and dress. Using calipers check the arbor diameter in several places and also the inside diameter of the arbor hole. I take the stone and lightly dress the 4 corners of the wedge. I've found it helps as a sharp outside square corner fitting into an inside square corner will bind unless it's perfect. This in no way affects the fit of the wedge/arbor/ barrel lug as you are only removing an almost imperceptible amount of metal. This may or may not cure the problem but it's where I start and it has worked in a couple of applications.

If the above doesn't cure the problem take some fine grinding compound, spread on the arbor and in the hole, assemble and rotate the barrel while moving it on and off the arbor. I've done countless valve jobs in my career and in my opinion the finest automotive valve grinding compound is too coarse for gun work but if that's what you can find use it.