Evaluating the CS on a PPC revolver?

[casimer]

Hello Everyone

A while ago I'd purchased a used PPC revolver - a DAO Model 10 w/ bomar rib, and 3" 'Sage Undercover 38' bull barrel. I don't shoot PPC, and am not familiar w/ how these revolvers were typically set-up.

What I'm wondering is whether the timing and profile of the cylinder stop are deliberate, or whether the stop is out of spec.

The cylinder stop contacts the cylinder early and has scratched a relatively wide cylinder line. The stop itself has the same contour as a stock stop, though it appears to be just a little flatter. But I don't know whether someone had taken a stone to it, or if it has worn down.

So my question is..

How do you determine when to change-out the cylinder stop on a revolver of this sort?

Otherwise the action seems right-on. I'd like to be able to use it in competition, but don't want to exacerbate a problem if one exists.

thanks

[Carmoney]

How do you determine when to change-out the cylinder stop on a revolver of this sort?

Dry-fire it as fast as you can cycle the action. If it ever feels weird like it's maybe skipping a chamber now and then, the cylinder stop and spring need replaced. If you know how to disassemble the gun, the new MIM stops are almost always a drop-in part, even on the older guns.

They flatten out a little from use. I wouldn't worry about it, other than I guess it is a sign that the gun has been shot a fair bit.

[pskys2]

Most revolvers push the cylinder stop onto the cylinder just a bit before it engages the recess. As they wear, you chamfer the chambers or mess with the hand the timing can/will slow down closer to the recess. At speed even a late timed (one that locks into the recess as the hammer falls) will shoot fine as the momentum carries it thru the locking. But if it's timing late and you stage the trigger or shoot slow it can be a detriment to accuracy, due to the round firing without the cylinder being locked. Introducing the possibility of chamber/bore misalignment.

My guess is most PPC shooting is done by staging the trigger or slowly stroking the trigger. So an early timed cylinder would be best. Sounds like what you have.

The only problem is if the Hand is fit too tight or on an older model isn't cut to length, then it may feel like it's dragging or binding on the last bit of trigger stroke. That's real noticable.

The wear marks are normal. And everything Carmoney said is of course the straight dope.

But, I'd bet you have an OS Cylinder Stop in it and a standard CS probably wouldn't fit. Powers makes and sells the OS CS.

As long as it locks up before the hammer falls and it passes Carmoney's speed check I'd not worry about it.

[chriss044]

IN timing a revolver the pawl that locks the cylinder should engage the cylinder prior to the hammer falling. This locks everything up so the bullet goes down the barrel instead of down the side. If that really was set up for PPC I have a few questions. Is there a stop on trigger? It should be something like a rubber pencil eraser looking thing. If it does have a stop of some sort, my guess is that it was meant to be shot that way. That means some PPC shooters like to put this stop in so that they can quickly pull through the trigger throw but just shy of where the gun goes bang. At this point then they can start to gradually increase pressure on the trigger (compressing the rubber stop) thereby having the triggger break more like a single action trigger rather than the DOA.

Edited January 4, 2009 by chriss044

[casimer]

Thanks for the responses.

I've tried rapidly cycling the action, and it locks every time. This has always been w/ an empty cylinder, but I haven't encountered skipping previously with a loaded cylinder either. There is some minor peening emerging on a few of the cylinder notches, like a burr at the top edge of the far face, but they're not visibly distorted.

Would an ovesized stop help to prevent further peening?

The cylinder timing is late in DA. It engages the stop just as the hammer is released. But in SA it's engaged at full-cock.

The revolver is rendered DAO using the trigger stop - when this is extended it limits the trigger's travel so that the SA can't be engaged.

There's no eraser tip on the trigger stop, though this could have come off.

The DA is very smooth, there's no perceptible drag, stacking, or camming.

Here's a picture of the revolver.

[Toolguy]

You need to adjust the hand or put in a wider hand to retime it. Also, you can get a flat bottom punch and hammer and gently

move the material at the edge of the notch back where it came from. Both of these conditions are just normal wear on a gun

that gets used. You can make the double and single action be set up for the same stop by setting the d/a to fall with 2 thicknesses

of paper behind the stop but not fall with 3. Then stone off the top back of the trigger for s/a so that it falls with no paper but not

with 1 paper. You have to keep this part exactly square and true to the sides of the trigger. Make sure the s/a doesn't push off

when cocked. I do mine on a surface grinder in a toolmaker's vise, but it can be done with a stoning jig or a disk sander that is

squared up exactly.

[Matt Cheely]

My PPC revolver cylinder locks just a bit before the hammer falls specifically so that I can lock it up, then shoot it like a single action. Much better accuracy than having the cylinder lock up right when the hammer falls. That way I KNOW when the hammer is all the way back instead of guessing.

[pskys2]

Actually it sounds as if you have a good Revovler now. Leave it alone and run it for a while before getting into anything else on it.

The Peening and marks are normal.

If it does NOT have an OS CS don't put one in. They won't help anything and it makes it harder to replace if needed.

[Allgoodhits]

Thanks for the responses.

I've tried rapidly cycling the action, and it locks every time. This has always been w/ an empty cylinder, but I haven't encountered skipping previously with a loaded cylinder either. There is some minor peening emerging on a few of the cylinder notches, like a burr at the top edge of the far face, but they're not visibly distorted.

Would an ovesized stop help to prevent further peening?

The cylinder timing is late in DA. It engages the stop just as the hammer is released. But in SA it's engaged at full-cock.

The revolver is rendered DAO using the trigger stop - when this is extended it limits the trigger's travel so that the SA can't be engaged.

There's no eraser tip on the trigger stop, though this could have come off.

The DA is very smooth, there's no perceptible drag, stacking, or camming.

Here's a picture of the revolver.

As noted by Carmoney & Toolguy & others, in addition I would suggest the following:

While fast stroking the revo the cylinder may have some inertia spin and simulate proper lock up. However if the timing is not right a very slow trigger pull may reveal another condition.

Pull the trigger as slow as is possible. Note when the cylinder stops rotating. Then without doing anything else, take your other hand and see if the cylinder will rotate any more. I am not talking about minor tolerance movement back and forth. I am speaking of not rotated quite far enough. In other words, sometimes if not timed properly, the cylinder will stop spinning (rotating) but not yet be engaged by the lug that scores the cylinder. This condition is often not diagnosed by the fast shooters. It likely is that the hand is not rotating the cylinder enough for it to lock up. The fast trigger puller, causes the cylinder to spin fast enough that the cylinder rotation causes the cylinder to coast to lock up.

Also, the absolute check should be done with dummy rounds in the gun, not just empty brass. The reason is that the loaded cylinder with bullets has more mass (weight) thus it takes more to spin it slowly. Also, the brass in the cylinder may give slightly different feel to the cylinder rotation as the hand is turning the cylinder, especially in the older guns that had the two pins that helped to stabilize the ejector. For the normal gun, and maybe even IDPA or USPSA use these last little things may never matter. However the HM PPC shooter is in pursuit of the best that can be achieved and some of these small details may enhance the accuracy, or the feel just slightly.

Lastly a rangeing rod should be used to check bore to cylinder alignment for optimal check of timing, lock up as well as a check for bent frame, yoke or other issues in the pursuit of a PPC revolver. Not 100% sure but I thought most S&W were set up to engage cylinder just prior to complete hammer spring compression, whereas many Colts and maybe Rugers it all happens about the same time. I think this is why many preferred the S&W for DA shooting. That was my preference.

Regarding the trigger stroke with a DA set up and a rubber trigger stop. Some would call this staging. With some guns you could actually remove your trigger finger at this point and the gun would be "similar" to as if in a single action cocked mode. However, it is different as different parts of the hammer and DA sear are utilized, but more importantly and a better description would be that this less refined initial trigger pull be referred to as "trigger prep" as opposed to staging. I think if one approaches it in this manner they will ultimately develope a better mental understanding as to what they are doing and ultimately get better, consistant results shooting DA with this set up.

It sounds like your gun was set up for some of the Undercover type PPC matches at the state/local levels. Many looked just like a full blown open (normally 6") PPC revolver, just shortened to 2-3" barrel length.

As always, results vary and game can be skinned with variation and get good results,

Martin

Edited January 6, 2009 by Allgoodhits