Register
Log In
Home
October 26, 2008
Offline
There are many postings and even magazine articles about checking timing on revolvers that would be applicable to Dan Wesson as well as most other revolvers. I won\'t go into great detail about checking although I will include some. The only one\'s that would be excluded are Colt\'s D/E/I frames (and the modern one\'s too). So assuming you know you need to fit a new one you can purchase one through DW, numrich (egunparts), jack first or on Ebay. Get a NEW unfit one if possible.
Dan Wesson hands engage on the side of the hand (like S&W, Ruger etc.) when in full lockup. So the thickness of the hand and it\'s fit within the frame window control lockup. Dan Wesson fitting ends up with the tip being filed/stoned down to get the proper thickness to carry the chamber up and engage the cylinder bolt (stop in S&W nomenclature) it should do this right as you engage the SA sear or as the DA sear disengages the DA strut aka hammer falls in DA (pending fitment and \"let out\" of DA strut) concentrate on SA because it\'s easier. You should also provide some drag on the cylinder with your finger to simulate the weight of being loaded to make sure that it carries up mechanically not just from the momentum of movement. Ok enough on checking.
Tool list: Micrometer, punches, couple screwdrivers, SAE allen wrench set, flat needle file or a not very aggressive file smooth cut, 400 grit sandpaper and a relatively fine stone (400 grit works for me) doesn\'t have to be a super fine Arkansas or anything like that.
This is what I do to fit a new hand:
Using a micrometer (not a caliper) measure your old hand make sure the new one is the same thickness or thicker preferably than the old. Write down the 2 measurements old and new. Lightly sand with 400 grit sandpaper the front edge that it rides on and the sides using the bench as a backer(just deburring and making sure it is smooth not polishing I don't even completely remove the bluing). The front angle down near the bottom controls how far the hand comes out of the frame. It needs to fully engage with the ratchet. On small frames this is easy to check just put it in and see if it remains in contact with the little angled support on the frame when cycled. If it comes off of the step just a little then it's fully engaged. Large frames you're going to have to look at the side of the gun between the recoil shield and the back of the cylinder to see if it's touching the bottom of the ratchet. This fitment on large frames most likely won't be able to be confirmed until the next step is done. As long as the general shape is the same (lay the old one on the new one) it\'ll be close enough for now. Make sure to come back and check though.
On the front right side of the old hand there should be an area that is filled down (looks like a step down) measure the thickness of that and write it down. If the 2 hands are substantially different thicknesses, a .005-.010 difference would be substantial IMO, then you will have to do the file and try method. Usually you can file to .010 to .015 away from the measurement and be really close. The safer way is to file and try several times. This area is the area that actually does the locking so try to match how far into the hand the old one is and make your cuts in the same basic spot. I find it easiest to hold the hand down with my thumb on the edge of the bench with the tip facing towards me at a 45 and do my file cuts. It seems to help me keep the file flat whatever system works for you. Make sure your step is flat, relatively smooth and is parallel to the body of the hand otherwise it will wear out prematurely. The hand must have the forward tension spring engaged to check fitment. On Small Frames you have to put the side plate back on I usually just hold it on with no screws until I am getting close. One thing to note the hand should be flush or just sub flush to the angled support piece on the frame. Large frames you'll have to put the transfer bar & spring in when checking (everybody's favorite part 😁) but the hammer doesn't need to be installed just cycle the trigger to check. Go very slow don't get in a rush it's much harder to put the metal back on. At some point it will carry up but be tight it may even lock the trigger back where you have to pull it to return. At that point use a fine stone, your file as a backer or something flat (hss tool bit is my go-to) to sand the step that you filed until it carries up, locks smoothly and allows the trigger to return. I leave mine just a little tight it's hard to describe they lock smoothly but there is a certain amount of resistance locking which goes away after shooting it 50 rounds or so. Mine stay that way when I fit them just a little tight.
One tip use a sharpie when you are fitting to show where the hand is engaging on the ratchet and remove metal only where it is removing the marker. This would be stone or sandpaper final fitting work but it will tell you how you did for keeping the locking surface flat and parallel. Ideally it should remove all the marker where it engages with the ratchet.
[Image Can Not Be Found]
[Image Can Not Be Found]
Hopefully you don't have to do this in order to get it. I have had to do it twice, my 741 and my Dad's 744, with a 3rd coming (my 7445). A brand new hand from DW was not wide enough to carry up tightly so it needed more thickness. The frame window was too wide to keep the hand in engagement with the ratchet, it would move over enough that with no fitting the gun wouldn't lock up consistently. A little bit of time with a TIG welder, then filing to the proper thickness and they lock up good and tight now. Use a large backer and clamp it to keep it from warping like a banana. To find the thickness (roughly) I used the "victim" hand and feeler gages in the frame window. I wish EWK would offer extra thick large frame and small frame hands.
1 Guest(s)
