VERY tight wedge on '72 open top

[Slo' Poke Pete]

Okay, I've got a pair of Uberti '72 open tops in .44 Special.  I've put the Gunslinger trigger/mainspring kits in both with a marked improvement in both guns there.  I've adjusted the arbor on one of the guns using the washer method and it's now ready for the range.

The other is a bit of a problem.  The wedge was so tight from the factory I had to tap it pretty soundly with a piece of hardwood to get it out and once it was out had to make a wedge out of the same piece of hardwood to remove the barrel from the receiver.  On the other gun the wedge came out easily and the barrel just pulled off the receiver.  When I put the wedge back in as far as it was from the factory it locks the cylinder up.

Looking thru the wedge slot in the barrel lug I can just see the front edge of the arbor slot and there's a drag mark on the muzzle side of the wedge.  When doing the 90* arbor fit test this gun is only off (arbor hole too deep) by about .003-.005, so the shim will be very thin to fix this.

My question/problem is this....by putting the shim in the arbor hole it seems to me that will increase the amount the arbor wedge slot will extend to the rear into the barrel wedge slot increasing the rearward force on the barrel to the face of the cylinder.  Do I need to lessen the width of the wedge (side to side) to allow this to mover more freely?   I understand from what I've read here to adjust on the cylinder side of the wedge, not the front.

I'm a pretty good DIY'er, but this is a first time operation for me.  Any and all advice will be read and appreciated.

Rob

[JohnsonBarr]

I had to adjust all four of my OT's wedges. I used a belt sander set up with 180 grit belt and slowly dressed down both sides a touch at a time until the wedges would go in with just thumb pressure deep enough to engage the retainer screw. If you go a little too far, replacement wedges are available from VTI and Cimarron.

[FriscoCounty]

Read Pettifogger's open top tuning guides.  The basic principles apply to all open tops.

http://www.theopenrange.net/articles/

[JohnsonBarr]

Hey Pete, as it happens I spent a little time at the range with my '72 OT this afternoon. Once I returned to my shop to tear down and clean, I realized that the '72 wedge is slightly different from earlier OT's (C&B). The '72 wedge has a rounded face on one side of the wedge, so any 'grind relief to fit' should be done on the flat side of the wedge.

[Slo' Poke Pete]

Hey Pete, as it happens I spent a little time at the range with my '72 OT this afternoon. Once I returned to my shop to tear down and clean, I realized that the '72 wedge is slightly different from earlier OT's (C&B). The '72 wedge has a rounded face on one side of the wedge, so any 'grind relief to fit' should be done on the flat side of the wedge.

Yeah, I had noticed that.  I don't think there'd be any way to maintain that radius on the muzzle side and I'm not going to try. 

Rob