Colt MK V Revolver Lock Up (How much is too much?)

[pipedreamer]

I have two .357 Colt MK V revolvers, a Lawman V (2") and a King Cobra (4"). How much "play" is normal on these revolvers during cylinder lockup? Both revolvers have end-play (cylinder moves front to rear) when the trigger is held to the rear. The gap is tight between the cylinder and the barrel (credit card test) and and a visual check for timing seems okay. Any advice would be appreciated. Thanks.

[kbcobra26]

I'm no expert or gunsmith but I'll chime in a little..

Any advice would be appreciated. Thanks.

Get some feeler gauges!!

Credit cards are almost 30 thousandths of an inch thick so that doesn't really tell ya much. If your gap is .010 or bit less than it's definitely fine, hell new Taurus specs allow for a gap .012 I believe..

Both revolvers have end-play (cylinder moves front to rear) when the trigger is held to the rear

When your trigger is held to the rear and your hammer is down this is called full lock up and it is the proper way to test your endshake/ cylinder play and having a little bit is normal (they all do)

So if you say your timing is good and if you ever get around to checking your cylinder gap with feeler gauges and it turns out they are in spec then I would say they are both fine and you have nothing to worry about.


Hopefully some real revolver guru's will chime in soon because I'm not one yet

[pipedreamer]

I checked both revolvers for barrel/chamber gap during full lock-up using a feeler gauge and they are .006" and this is a tight fit. I also have a D frame Detective Special and it has no cylinder movement front to rear when in lock up. All are early 90's made guns. Is there a difference in the mechinisms that could account for this difference in end-play?

[Manxdriver]

KbCobra knows nothing!! Both of those guns are DANGEROUSLY out of spec !! Do not fire them. Give me your address and I'll come and get rid of them for you. I'm such a nice guy that I won't even charge you the normal fee for my services. Of course if you want to pay the transfer fee, well, that'd be mighty nice of you.
Kidding!!! I concur with exactly what he said, and I am insanely jealous of your collection of horseys!

[Neko456]

I've owned a Trooper (not the hand fitted one) and now own a King Cobra front to rear movement in not as important as side to side movent of the cyclinder once locked up. Usually with the trigger in single action there nearly no movement r-l or s-s and thats called a tight lock up. As as long the guns are shooting straight, I wouldn't be that concerned with backing forth movement before lock up unless a big gap.

[Seabee CO]

Concur with the above poster, you need to get a set of feeler gauges from you local automotive supply store.

My King Cobra Stainless Steel Enhanced gauges out on a tight 0.004" and a "no go" on 0.005" when "locked up" (trigger depressed and hammer down). There is still a small amount of play in the cylinder when locked up. Same with my Anaconda - both the King Cobra and Anaconda have the same lock work. This is normal. My Smith and Wessons have this as well to a degree.

Now my Pythons and Diamondbacks lock up tight with absolutely no play, but that is an entirely different game altogether.

Hope this helps.

[pipedreamer]

My revolvers guage out at .006" while locked up (hammer down and trigger held to the rear) with me pushing the cylinder back as far as it will go towards the hammer. What concerns me is the movement front to rear when locked up. You can move (push) the cylinder back and forth front to rear with noticable movement. This is not the case on my D frame Colt or on my S&W. I was lead to believe that cylinder movement on the V frames was the result of cost savings by Colt? Obviously, these are not our grandfather's Colts! I guess the bottomline, what is "normal" cylinder play for a V frame Colt?

[shiloh]

A slight amount of end shake on the Mk V is normal. Here's a post on the Colt Forum about end shake on the King Cobra, which has the same action as the MK V Trooper and Lawman:

http://www.coltforum.com/forums/colt...end-shake.html

The bottom line:

The maximum end shake on Colt revolvers is 0.003.
Barrel/cylinder gap is out of spec if it's over 0.008.
Ideal gap is 0.005.
Minimum gap is 0.003

The MK III and MK V Colts have completely different lockwork than the earlier Colt DA revolvers, like the Python, Diamondback and the original Trooper. On those earlier models, on firing the "hand" engages the cylinder along with the bolt stop so that there is zero movement, either rotational or back and forth. The change in lockwork in the MK III and MK V models was indeed a cost-saving measure by Colt (the MK V also saw a change to a shorter hammer fall and longer mainspring, for a faster and smoother trigger pull). They are all very fine revolvers, very strong and reliable.

For what it's worth, if you find that the end shake on your MK V is over spec, Colt still services those guns. Contact info for customer services is here: http://www.coltsmfg.com/Contact.aspx

[pipedreamer]

Okay, great info--thanks! Looks like the gap is in spec at .006, but how do I measure the "end shake"? I got a gap of .006 while pushing the cylinder rearward to open up the gap as much as possible (while in lock up). Without pushing the cylinder towards the rear I get a gap of about .005. If "end shake" is the measurement of movement of the cylinder from forward rest (.005) to pushed all the way back towards the hammer (.006), then my guns are right on the factory spec for gap (.005) and there is only .001 amount of movement front to rear???

[shiloh]

To measure end shake, push the cylinder as far forward as it will go, and measure the barrel/cylinder gap with your feeler gauges. Then push the cylinder back as far as it will go,and measure the gap again. The difference is the end shake. As long as it's 0.003 or less, you're in Colt's specs and good to go.

Edited to add - both measurements made while the cylinder is closed, of course.