Refurbishing a S&W 638-2 Airweight and Trigger Job

[Fudmottin]

It's been a long time since visiting this forum. I checked the rules again and I think this is the place to ask. I have more than one question about this revolver.

Back in the late 1990s, before I knew what to look for in a used revolver, I purchased a S&W 638-2 Airweight. It has always had a problem with the cylinder hanging up. I think it's at the back, but it could be the front. There is no obvious distortion in the ejector rod or crane. Any ideas on how I can fix this? Thanks to YouTube videos, I'm willing to open this up and have a look.

I've actually opened it up to clean it out (just grip and side plate removal) because the cylinder wouldn't spin. It turned but wouldn't spin nicely. I opened it up to flood it with cleaner and also get some lint out. There exists light rust on the hammer which I think can buff off with due care. Strictly cosmetic. I over lubed it and have to get the excess out I think. While the cylinder hangup always existed, it seems more noticeable now. Sometimes it really does not want to open.

The forcing cone area has a significant build up of carbon. Is it safe to use brake cleaner or other harsh solvents that dissolve carbon? Would taking it to my local Targetmaster in Chadds Ford (202 N in Delaware Co) for sonic cleaning be a good idea?

I have metric gap feeler gauges. What is the specified cylinder to barrel gap for this revolver?

The previous owner scratched up the finish around the middle side plate screw. I do not know if a badly done stone job was attempted. I have already ordered a spring kit for lighter trigger (Apex J-Frame Duty/Carry Spring Kit). I probably jumped the gun on that one (no pun intended). Obviously I would like to get the other issues sorted before installing it. The question here is, assuming no internal parts were messed with by prior owner, how is the alloy frame actually finished and is there a way I can fix the scratches or possibly refinish the frame? I do not have the required tools to remove and replace the barrel.

I would like to keep the 638-2 because the -3 has that stupid looking trigger lock and reasons. I also want to avoid spending too much money as I recently bought another firearm. I was inspired to pull the 638 out because of a YouTube video (hickok45's channel). Seeing the MSRP of the new guns, I think it is worth putting this revolver in order as I have a nice Kramer pocket carry holster for it and have carried it in the past.

I can post pictures if requested. Thanks.

[gold cup abuser]

barrel to cylinder gap should be .005 inches.

if the cylinder is not rotating properly you will need to possibly change the extractor star and the ejector rod. cylinder pawl might also be suspect. Numrich or Smith will have the parts needed.

you can clean the throat area with some Lead wipe away cloth and a bronze toothbrush soaked in Break Free or Hoppes #9.


be careful on those springs you ordered. they may create more problems than they solve. Get it working as is, then test fire it a few times. If the trigger pull is still heavy, then change the springs.

an attempt at a trigger job can be detected by inspecting the side plate and the rebound slide. If they look shiny with an absence of tool marks, then someone tried to do a trigger job.

hope this gets you started on the right path.

good luck and happy shooting

[GrumpyOldRetiree]

At the risk of asking a stupid question: Does the cylinder spin freely when it's open?

[Fudmottin]

At the risk of asking a stupid question: Does the cylinder spin freely when it's open?

Yes, it does. I sprayed some stuff in there that got it spinning nicely. Although I think I should pull the crane and get any carbon fouling out. I saw a YT video on that.

[Fudmottin]

barrel to cylinder gap should be .005 inches.

hope this gets you started on the right path.

good luck and happy shooting

It does indeed! Thanks.

[Fudmottin]

I've got a video up on YouTube to show the problem I'm having. I sincerely apologize for constantly saying "cylinder" when I mean "chamber".

I stripped the frame and cleaned things up best I could. Since I had it open, I went ahead and installed the Apex spring kit anyway. While I haven't shot it yet, I'm pretty confident that the Apex main spring will light off any primer.

The problem with opening up the cylinder has not changed. I think the problem is with the ejector star. I would love an educated opinion though. When one of the chambers is at the top, the cylinder opens easily. The other four snag. It should be all visible in the video. At the moment I'm making this post, it is an unlisted video. I will make it public soon though. It takes YT a bit of time to properly process HD video.

https://youtu.be/bGVxn62cYqo

Thanks in advance!

[Gunsnwater]

I bought a used 640-1 that had the same problem. The yoke or crane if you will was bent. You need a ground pin to put in, in place of the cylinder assembly, to check alignment. After straightening out that, it was still a little sticky on the thumb piece acton but not when it wasn't pushing the cylinder pin. Turned out that a dremel with a buffing wheel and some red polishing compound fixed that. You need the tools ffom Brownells but it is not hard. When you bend the yoke you won't believe how little pressure it takes.


I had to straighten a yoke on a model 64 police trade also. Some jack wad was wrist flicking the cylinder closed like he was in a movie. That one required a new star also. Had to have a smith fit that one. He was near Dixons muzzleloaders in Kempton. Very good work, reasonable price. Actually he was so low I made him take more.

[Fudmottin]

Ouch. A bent yoke/crane was one of the things I did not want to hear. You were able to see too much gap in my video? I've also got pictures. I took pictures each step of the way when stripping the frame to make sure I would know exactly how everything went back.

SW_638-2_Crane.jpg

What do I look for one the Brownells site for the tools? I don't even know what they are called. A URL would be particularly handy.

If the yoke is so easy to bend, I can see why wrist flicking the cylinder closed is a bad thing. I'm guilty of doing that myself on my 629 .44 Magnum. I've since been told off and don't do it anymore.

Thanks.

[Fudmottin]

I threw a bunch of search terms at Google and came up with these:

http://www.brownells.com/gunsmith-to...-654-2800.aspx
https://www.brownells.com/userdocs/l...ign%20Tool.pdf

The above looks like a bit of work. But it is affordable and I believe I have the appropriate tools for the job. Then there is this.

http://www.brownells.com/gunsmith-to...-prod9846.aspx

There's quite a bit of sticker shock going on with that one. Perhaps if I was a professional gun smith. LOL. So should I go ahead and purchase the first one?

[Gunsnwater]

The first one is for checking the alignment. Make sure you get the j frame one. The second tool doesnt work with j frames. Its too big. However I used the rod off of it for the leverage to make the adjustment. So you will need a small pipe or drilled out bar.