Power Custom oversize latch / Single Six

[Pat C]

Some may remember my old 1993 Single Six that always seem to let me down in accuracy dept. But its looks always kept me interested. After ruling out ammo as any change I sat down and did a detail study of the gun. What I found was the barrel cylinder alignment was off terrible over indexing and very sloppy lockup . I could move cylinder .018" radially when fully locked. Worst one Ive ever encountered.

Thought about sending it to Ruger but through Kuhnhausens shop manual I learned how to fix it .And thanks to Power Custom for offering a product to make the fix.

Typically this gun was lucky to produce 4-5" groups at 20 yards offhand . Not much better off rest.

[Pat C]

First thing to do was tear it down and check measure the frame latch window and timing to the cylinder notches.
What I found was with range rod in the bore/cylinder looking up from bottom of frame the Left side of window was lined up with cylinder notch but the right side was way oversize causing the looseness.

[Pat C]

To start I ordered the oversize latch from Power Custom .
It measures about .007 larger in width than factory. This always you to fit sloppy window and shift lockup timing.

First thing was to use pin guages to measure window which was already very large I only had to use needle file to open .002 of back of window so it had .001 clearance over latch itself.

[Pat C]

So now comes the timing lockup change . So I already determined it was over indexing. And left side of window looking up was aligned. This means all the material is milled off opposite side. And you only need to mill what's sticking up above frame .

The width is milled to .001 clearance under tightest locking notch of cylinder.

[Pat C]

Next the top of the latch head sticks up too high to allow perfect fit. You file and or stone until its flush with frame when gates open . Then you check the hammer timing when you let hammer down the leg of latch slips off detent inside when hammer is 1/8" or so from full drop.

On e all this is checked and fit you polish head and other contacts with cratex Bob on dremmel.

[Pat C]

Now when assembled I have tight lockup that passes range rod. So now for the test does it shoot better.

Why yes it does , much better here's two offhand groups at 20 yards.One sitting and one standing . But both just around 3" and 18 shots each.

[JimT]

Nice work.

I had an old model 357 that I shot until it was loose. The bolt had battered against the frame from years of cocking really fast, and it got wobbly on the screw and messed up the lockup.

I shimmed the bolt into place and put in a new screw and it ran just fine, didn't spit or lose accuracy. But the oversize bolt is really the way to go.

[Pat C]

Jim , this one was just sloppy I bought it used on Gunbroker as a cheap shooter seceral years ago. The bolts from power customs make quick work of these issues. And Kuhnhausen shop manual. Ive got the sights adjusted and if weather is decent tomorrow I may try a rest and see what the 4 5/8" will do. Im already pretty happy .

[Scott Tschirhart]

Great explanation and photos! This was very informative.

[AJMD429]

.
Wow what a helpful post.

I need to check mine out.

(I hope I can find something to blame for bad groups aside from a bad trigger-nut*...

(* the nut behind the trigger - i.e. ME... )

Still even if it is me, a helpful troubleshooting post.

Thanks.

[Pat C]

Going forward one thing one should always check is barrel cylinder alignment .Cock hammer and insert proper range rod made for the caliber .Ideally it should go all the way from bore to chamber and no resistance.

Pacific Tool makes really nice range rod sets . You can also use precision pin gauges.

True forcing cone is also a accuracy influencer.
I plan to get Skinner's Belt Mountain base pin soon.

[Pat C]

20 yards with me sitting on ground with gun rested by bag .
12 shots 1 1/2" span .

[Pat C]

Few more adjustments on sight and bingo .

[Pat C]

Got the steel ejector housing from Ruger installed much nicer than aluminum alloy.

[Walt]

You can certainly take pride in doing a job like that yourself. Nice work, Pat!

Isn't it nice to have a "new" favorite gun?

[piller]

I need to print this thread and file it away.