Problem installing endshake bearings in SP101

[My Toy]

I ordered a set of endshake bearings from Brownell for a SP101 I just acquired; actually they are Power Custom products that the packaging says they are for Colt Anaconda, Ruger SP101 and can be used as trigger shims in a 10/22. In the cylinder I wasn't able to get the endshake bearings past the sloted fastener the holds the extractor assemble in the cylinder. I've installed endshake bearings in a couple of GP100s that have the same kind of arrangement in the cylinder with no problems. If you were to use the bearings I got it looks like you would either have to disassemble the extractor assembly from the cylinder or somehow enlarge the hole in the .004 bearing to fit over the fastener. I know you need a proprietary tool to disassemble the cylinder which is not generally available outside of the Ruger factory. I've read other posts where people have installed these bearing in their SP101s and there is never any mention of this problem. Has anyone else encountered this.

 

[JB696]

You will need to disassemble the extractor to install the shims. The extractor retainer screw is a left hand thread with a dab of loctite on it. It takes a split tip hollow shank screw driver to remove it. If you are handy you can make a special screw driver yourself by cutting a slot in the center of a regular screw driver. The tip I use came from Brownell's and the number on it is USA 080-432-001. First I heat up the retainer for two or three minutes with a candle flame and then loosen it by turning clockwise (left hand thread). It is trial and error on the shim thickness. On final assembly apply a small amount of blue loctite on the threads and tighten up gently. If the parts are clean the loctite will secure it well and there is no need to cinch it down too hard. The retainer screw is very delicate and if you mess it up Ruger will not sell you another one and you will have to send them the gun to get it fixed.

Incidentally, since the shim goes between the rear of the crane tube and the inside rear of the cylinder, the cylinder will be moved a few thousandths to the back of the frame window. This will take up some of the endshake. But it will also increase the barrel to cylinder gap. So if the gap is already at the limit then you might re-consider installing the shims. I prefer .002 to .005 for a barrel to cylinder gap with the cylinder pushed all the way to the rear. And a slight bit of endshake is alright with me because it prevents the cylinder from binding when it gets hot or when there is a lot of carbon buildup during a long range session. Good luck.

 

[Carry_Up]

Before you throw parts at your revolver, determine if it actually has excessive end shake. You will have to first measure b/c gap and headspace to calculate it. A revolver needs some amount of endshake otherwise you will bind up the cylinder after a few shots. But, if you need to adjust it, buy the Magnatip tool from Brownells to get the cylinder apart.

Note the orientation of the ejector return spring during re-assembly.

CU