41mag Posted January 29, 2008 Share Posted January 29, 2008 Hi folks, I don't have this gun in my hands yet but will in the next day or two, it belongs to a friend of mine. When I dropped by the other day he let me fire it and I of course fired it double action. I dry fired it first to get a feel for the trigger and there was a couple places where I could feel it hanging up. I then proceeded to locate the problem and found that the cylinder was hitting the barrel, not all the way around but in a couple of spots. He had been shooting lead and there was some build up on the cylinder so he cleaned it off. I then dry fired again and it was fine. I started putting some rounds down range and on the third shot it was back to rubbing. I didn't measure the end shake yet but it didn't feel bad. The BC gap did look pretty tight (not measured yet). My guess right now is that the endshake is to much for the tight BC gap and the cylinder moves forward during recoil. I also think something might not be square as it doesnt rub all the way around. I couldn't tell that anything was bent or out of alignment by spinning the cylinder and looking at it paying attention to the ejector rod. The gun is a 25-5 S&W 45 Colt. I told my friend that I would get to the bottom of the problem and fix it for him if I could and that I had a great resource at my side with all the knowledgeable folks here on the Enos revolver forum (sucking up). I thank you for any help in this matter that you can give me. thanks, 41mag Link to comment Share on other sites More sharing options...
Ignatz Posted January 29, 2008 Share Posted January 29, 2008 Maybe if they are reloads, a high primer could be draging on the back of the frame causing it to drag. Something easy to check. Link to comment Share on other sites More sharing options...
Waltermitty Posted January 29, 2008 Share Posted January 29, 2008 Brother Pat, End shake is the amount of movement front to back that the cylinder makes when the cylinder is pushed fully forward versus fully rearward. I don't have the manual in front of me, but S&W may have an upper limit of .002" on this. I try to maintain .001" or less but not zero. Too tight and the gun won't be reliable under expected use conditions. This dimension is the relationship from the end of the crane, through the ejector star to the bearing surface in the frame of the gun. I usually measure the gap at the barrel end although I have read you can do the same from the cylinder face to the frame. What must be set is the location of the crane(yoke) bearing surface in relation to the rest of the gun. This is done in two places. One is to set the yoke to the gun. The other is to set the end of the yoke to the back side of the star. The yoke must be right first. You must determine if the end shake has movement with the yoke (crane) involved when locked up. The reason for the tapered groove in the part of the yoke that goes into the gun and the spring loaded screw that holds it in is to try to force all of the slack out of the yoke to frame assembly. If that's all working and the yoke isn't moving then forget about it and move on. If it is moving it is (hopefully) going too far into the frame and can be shimmed so that it won't move forward and rearward. Once that is fixed you move to the cylinder/yoke assembly. If the barrel gap is too small (about .003" or less on a work gun) or end shake is too great (>.002") you add shims inside the cylinder (the ejector star/rod assembly must come apart) to space it off of the end of the yoke. Here's a link if you don't already have it: Brownells There are different thicknesses. I like to face the yoke so I can put two .002" spacers in the assembly and end up with between .0005" - .001" of end shake. The shims become the sacrificial bearing surface so as the miles build up and endshake increases I can tear it down, replace the shims and be back to where I originally setup the gun. As far as the dragging not being even around the cylinder, I wouldn't worry about that. Many cylinders and forcing cones aren't perfectly square and many have an intentional angle going into the gun to ease entry for the cylinder. Just pick a point to measure and stick with it (e.g. barrel/cylinder gap at 12 o'clock position). Link to comment Share on other sites More sharing options...
David Sinko Posted January 30, 2008 Share Posted January 30, 2008 I bought my beloved 625 used and promptly had some custom work done to it. I had the barrel cut down to 4" (before S&W realized a 4" 625 would be a good idea) and immediately experienced the same symptoms. It dragged enough (on only a few of the chambers) that it was a real problem. I took the gun back to the 'smith and I think all he did is turn the barrel out one turn. This certainly solved the problem and while I'm not sure it was the best way to do it, I haven't had any problems since. Dave Sinko Link to comment Share on other sites More sharing options...
Bubber Posted January 30, 2008 Share Posted January 30, 2008 Pat, I would lean towards Waltermitty's solution. It is the fastest and cheapest. I had to turn a barrel once and that was only because i replaced the barrel on my 625. For some reason it was shot out. For just a little over $100.00 I got the stuff to do the job. Shims are a lot cheaper if you can go that route. If you are lucky it will be the endshake bearings (shims). I am not a real fan of the Yoke bearings, but have replaced many a endshake bearings in my worn out revos. Later rdd and good luck Link to comment Share on other sites More sharing options...
41mag Posted January 30, 2008 Author Share Posted January 30, 2008 Thank you kindly gentlemen. This will certainly give me a place to start when I get a hold of the gun. I will try to get it tomorrow. I will post my findings here with possibly some more questions. After studying Ken's great post I am wondering if its possible that the screw that keeps the cylinder in the frame could be loose or worn? That would be an easy fix! I will check for that asap. I have heard of this screw being worn bad enough that some folks have pushed the cylinder out of the gun during a reload. So maybe recoil could push it forward also if its worn? thank you, 41mag Link to comment Share on other sites More sharing options...
HSMITH Posted January 30, 2008 Share Posted January 30, 2008 Check the throats on the gun, 25-5's can have HUGE throats and will lead terribly in just a few rounds. If the barrel/cylinder gap is on the tight side they can lead enough to drag in just a couple rounds. Waltermitty has provided excellent advice if it isn't as simple as lead build up. Link to comment Share on other sites More sharing options...
Greg in VA Posted January 31, 2008 Share Posted January 31, 2008 Before you go to any trouble like buying shims or turning the barrel out, check to see if the crane is bent. What you are describing sounds like the crane is bent and causing the cylinder to drag on just a few chambers and missing the others. Greg in VA Link to comment Share on other sites More sharing options...
41mag Posted January 31, 2008 Author Share Posted January 31, 2008 (edited) Got to look at it today....Push the cylinder toward the barrel and it will contact at the top, 0 BC, then push toward recoil shield and then I can insert a 6k feeler gage. My friend was hesitate to order the shims until he compiles a larger order so its on hold for a while I guess. Greg, I can't tell by looking that the crane is bent, is there a proper way to test? And thanks for the tip. The crane is not loose in the frame. Our plan right now is to try the shims first (when he gets them). On a personal note, I need to order those "Kuhnhausen books" (spelling ?). I really hate not knowing what needs knowing on the Smith revos. I have enjoyed doing my own trigger jobs and general tinkering tremendously and want to continue building knowledge and experience. thanks again everyone, 41mag Edited January 31, 2008 by 41mag Link to comment Share on other sites More sharing options...
Greg in VA Posted January 31, 2008 Share Posted January 31, 2008 Brownells sells a part called the crane alignment tool. On all the revolvers I work on I start there, I make sure the crane is right, then I get the cylinder to run smooth, then I get the cylinder to run smooth in the gun. After I make sure the cylinder is right I move on to the other stuff. The tool comes with instructions on its use. Greg in VA Link to comment Share on other sites More sharing options...
bountyhunter Posted February 1, 2008 Share Posted February 1, 2008 (edited) Thank you kindly gentlemen. This will certainly give me a place to start when I get a hold of the gun. I will try to get it tomorrow. I will post my findings here with possibly some more questions. After studying Ken's great post I am wondering if its possible that the screw that keeps the cylinder in the frame could be loose or worn? That would be an easy fix! I will check for that asap. I have heard of this screw being worn bad enough that some folks have pushed the cylinder out of the gun during a reload. So maybe recoil could push it forward also if its worn? thank you, 41mag When ever you check B/C gap (and end shake) manually push the cylinder forward and take a reading, then back and take a reading. Take readings at all six tube locations. Also, check the gap at the breech face to cylinder. If that one is a shade high and the B/C gap is a shade low, you've got an easy fix with shims. If the breech face gap (called headspace) is too tight or right on minimum, shimming the cylinder will cause it to bind there. Edited February 1, 2008 by bountyhunter Link to comment Share on other sites More sharing options...
bountyhunter Posted February 1, 2008 Share Posted February 1, 2008 Got to look at it today....Push the cylinder toward the barrel and it will contact at the top, 0 BC, then push toward recoil shield and then I can insert a 6k feeler gage. My friend was hesitate to order the shims until he compiles a larger order so its on hold for a while I guess.Greg, I can't tell by looking that the crane is bent, is there a proper way to test? And thanks for the tip. The crane is not loose in the frame. Our plan right now is to try the shims first (when he gets them). Becareful to smooth the inside surface of the cylinder that the end of the crane tube runs against. The tube will usually wear a groove there. The shims are the same outside diameter as the tube, but extend farther inside. because of that. they will bind up if the inner part of that ridge is not smoothed off. hard to explain, take my word for it, the inside needs to be flat for the shims to fit right. Link to comment Share on other sites More sharing options...
41mag Posted February 1, 2008 Author Share Posted February 1, 2008 Thanks for the info, I am grateful. Anyone know what the headspace should be? 41mag Link to comment Share on other sites More sharing options...
8shooter Posted February 2, 2008 Share Posted February 2, 2008 I had a .357 that the cylinder timing was out slightly for 2 or 3 chambers on the cylinder, it was found that was causing a lot more leading in the cylinder/barrel gap area, I had Randy at The Handgunner in PA fix the timing on those chambers and the leading problem disappeared, still get the usual leading in that area but not excessively that it rubs on the cylinder. Maybe another thing to check. Link to comment Share on other sites More sharing options...
Rogan Posted February 2, 2008 Share Posted February 2, 2008 The gap between the cylinder and forcing cone should be between .004 and .010, while the cylinder to breech face should be between .060 and .068. If you can't get these dimensions, then the overall distance between the forcing cone and the breach face is too small for the cylinder you have in the gun. The forcing cone would have to be moved, either by loosening the barrel as bubber did or shortening/squaring the face of the forcing cone. There maybe other solutions, but those are the two that come to mind. Link to comment Share on other sites More sharing options...
Bill Nesbitt Posted February 2, 2008 Share Posted February 2, 2008 I have an old 25-2 that I broke the hammer pin on. I sent it to S&W and they said the barrel needed turned in a turn also. When I got it back the cylinder rubbed on the barrel in a couple of spots just like you describe. I sent it back to S&W and as far as I can tell, they fixed it by putting a new screw in the sideplate that holds the cylinder in place. Seems to be OK now. Link to comment Share on other sites More sharing options...
z40acp Posted February 2, 2008 Share Posted February 2, 2008 If after checking everything else thoroughly and you need to remove some of the barrel {barrel to cylinder gap}. You don't want to just back the barrel off one turn. Brownells sell a nice kit to do that without removing the barrel. While you are doing the gap, recut the forcing cone for a 11 degree angle. You can cut it much smoother than factory and 11 degrees is better for lead bullets. I recut a 629 that was very accurate with jacketed but not so with lead. Shrunk the groups considerably. Link to comment Share on other sites More sharing options...
Bubber Posted February 3, 2008 Share Posted February 3, 2008 If after checking everything else thoroughly and you need to remove some of the barrel {barrel to cylinder gap}. You don't want to just back the barrel off one turn. Brownells sell a nice kit to do that without removing the barrel. While you are doing the gap, recut the forcing cone for a 11 degree angle. You can cut it much smoother than factory and 11 degrees is better for lead bullets. I recut a 629 that was very accurate with jacketed but not so with lead. Shrunk the groups considerably. +1. I did not just loosen the barrel I had to replace it with a new one and recut it. Sorry if I was unclear.. later rdd Link to comment Share on other sites More sharing options...
rifleman Posted February 18, 2008 Share Posted February 18, 2008 2/17/08 Im sure that your friends pistol will be in good hands! Mike Link to comment Share on other sites More sharing options...
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