Colt Police Positive DA Timing Issue

[jimkim]

I'm working on a Colt Police Positive. When I first got it, the timing was off so bad the pin wasn't even hitting the primer. I stretched(peened) and timed the bolt, AND filed the pawl/hand until it is perfect in SA. The problem is, it is still off in DA. It rotates a bit far. Any suggestions. I thought I would ask, before I do this. The last time I touched one of these was 1992 or 1993. My memory isn't what it used to be, and the last thing I want to do, is start over.

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[Petrol & Powder]

The Colts are different from the S&W and Ruger DA revolvers. The Colt locks at the moment the hammer is released and the pawl (hand) holds the cylinder tight at the moment of hammer release. You can sometimes displace enough metal (peen) the pawl to get enough extra length to get where you need to be but usually a new longer pawl is needed. Colt parts can be difficult to find.
Another option that I've seen, with varying degrees of success, is building up a little metal on the pawl and then fitting it.

The timing difference you're seeing between SA and DA is the result of excessive clearance between some of the parts. When you pull the hammer back with your thumb the hammer pulls the related components with it (the trigger, pawl, etc.) . When you use the trigger to cock & release the hammer in DA the trigger pushes those related parts. Excessive clearance between some of those parts (particularly the trigger and pawl) will allow that action to work in one mode (pulling) but not in the other (pushing). The pawl interfaces with the trigger via a small hole in the trigger and a pin on the bottom of the pawl; that is one area that will allow SA to work but DA to fail if the hole is too large or the pin too small. Again, a new pawl is generally the fix. There are other areas that can cause the same problem.

[No Blue]

My late gunsmith friend always pointed out Colt revolvers were a real challenge compared to S&W, looks like he wasn't making that up....I guess it comes from the 100+ year old design and machinery Colt used.

[Genecockrell]

The older colt Official Police and Pythons with leaf springs and no transfer mechanism use two steps on the hand.. You may want to take a look at this although to be honest I don't know if the coil spring Police Positive has this...

[jimkim]

This is the old model. It has the leaf spring. I was thinking the pawl may be a bit long. It rotates too far in double action, but is centered in SA. The timing on the bolt appears to be correct(as soon as the hammer begins to move it does too, and it sets back down in scalloped portion of the groove as soon as the hammer locks) now. It was way off to begin with. I thought about ordering a new cyl assembly, pawl, and bolt, and refitting everything. The cyl looks like it's been rode hard and put away wet too.

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[Petrol & Powder]

When you say it rotates too far in DA, is that observed when the trigger is pulled slowly?

If you stretched the pawl (hand) by peening, you may have over done it a bit. If the hand is too thin where it passes through the frame (window) the lateral movement can cause the same problem in DA.

Before you started the repair was the timing slow (the cylinder doesn't index before the hammer falls) ?

[jimkim]

Slow or fast, it makes no difference. To begin with it didn't rotate(when it wouldn't jam) far enough to hit the primer. It was in sad shape. It looked like it had a hundred years worth of oil and clay in it. Once I cleaned it, it stopped jamming as much, but the timing was still bad. One thing I noticed was the hand/pawl was bent a little too. It was curved toward the outside. It really has been abused over the years.

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[KenT7021]

I would try fitting a new hand.Numrich should have some new production hands available.I wouldn't bother with a used part unless there is no other option.

[Petrol & Powder]

I would try fitting a new hand.Numrich should have some new production hands available.I wouldn't bother with a used part unless there is no other option.

Agreed

[jimkim]

I wish there was a "like" option. Thanks for the help. For around $100.00 I can get a new cyl assembly, hand, and bolt. Seriously considering replacing all of those.

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[Genecockrell]

You may want to try the hand and pawl first. If you replace the cylinder then you are going to have to not only get the timing right but then probably deal with headspace and barrel cylinder gap... These may be OK but maybe not. If the hand was bent then you may want to get one.. Numrich among others should have this.. The Python hand should work too as the Python is almost identical to the earlier leaf spring guns internally. You do want to make sure the stop that comes up from the bottom of the frame and pops in the groves in the side of the cylinder doesn't have any back and forth wobble, also that it comes up enough to engage.. Honestly the first thing I'd check are the springs and a really good cleaning..

[jimkim]

First thing I did was clean each part. No back and forth wiggle, on the bolt. I have close to a hundred hours(if it wasn't a family heirloom, I wouldn't have touched it) in it now. There was a lot of tweeking from one side to the other to get it to work in SA. The springs are good now. I replaced the one on the bolt. It was weak, and the bolt wouldn't lock the cyl at first.

The heirloom thing is due to it being carried by the first black deputy in this county. It's important I get it operational for his family.

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[KenT7021]

The Python hand will not fit the Police Positive.I would not replace the cylinder or ratchet unless absolutely necessary.

[KenT7021]

I just checked the Numrich website.The hand that will you need is P/N 174800A priced at $24.30.

[jimkim]

Thanks.

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[2152hq]

When you say it's 'over timed' in DA,,pushing the cylinder too far,,is the cylinder bolt not dropping into place on DA and locking the cylinder in place at the correct position preventing it from going past lining up w/the bbl?. That sounds like a cylinder bolt problem in DA.

OR,,'over timed' in DA mode,,do you mean the cylinder bolt will drop correctly, the cylinder locked properly in position but the hammer still retracted and not able to go any further. The trigger also at a point to the rear where it can't be pulled any further.
All this because the hand is pushing against the ratchet tooth of the now locked into place cylinder.


If the latter is what is happening,,and the SA mode is perfectly in time,,the proper 'fix' is to carefully relieve the DA sear/strut a tiny amt. That will allow the hammer to fall at this point when the cylinder is locked (timed) in DA and no further rearward motion of the hammer is needed. The trigger will then slip out from under the DA strut on the hammer and allow the hammer to fall in DA mode with the cylinder locked by the bolt.
No effect on SA timing ,,that will stay the same.

If the former is happening ,,then you have to determine why the bolt will not drop in DA mode allowing the cylinder to roll by the indexing point.
Once you get it to work right you can use the above method to time the DA release and not effect your already good SA timing.

[jimkim]

Thanks I'll check that next.

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[Char-Gar]

Fired DA the cylinder mass when it spins creates inertia and the bolt is not rising fast enough to lock in the cylinder notch. Cocking SA allows the lazy bolt to do it's thing.

Cock the hammer SA and then lower the hammer while holding the trigger at the rearmost position. Held back the cylinder should not have any wiggle. If it passes this test, you can be certain the hand is not your problem.

Now the bad news, some firearms are worn beyond any reasonable repair. To rebuild one is just not the effort nor money involved. Some heirlooms are better left non-firing anyway. I realize some folks want to shoot Great Grandads pistol, but that might not be a good idea.