S&W 67 cyl to barrel gap?

[Bobster]

Hi all,

I just got a used model 67 revolver in ss. It looks ok, but I was wondering what the gap at the cylinder forcing cone juncture should be? What is too much, what's good?

Bobster

Niner #283

[DJ Niner]

Lots to consider here, but here's the general guidlines I use.

Around .005"-.006" is about what I want; loose enough to function even if dirty AND hot, tight enough for decent accuracy. Go plus or minus .002 here. But...

Anything tighter than .003", you'll probably have functioning problems with the average SW after firing a bit. Custom guns, or Freedom Arms revolvers can get away with this tight (or tighter) gap because of superior fitting; the average SW will begin to bind because of crud buildup or heat expansion. And...

Anything on the far side of .008" MAY give accuracy problems, and certainly will bleed-off some power. I say MAY have accuracy probs, because I have seen a few guns shoot well with larger gaps, but they were DEFINITELY the exception to the rule, in my book.

All this assumes good/excellent timing, headspace, hammer strike, etc. Check each chamber, too; don't be surprised if one or more varies by up to .002". All depends on the quality and attention of the person who did the original fitting (and use/wear since, of course).

Hope this is helpful...

[Bobster]

Yes, very helpful. I found a reference that said to cock the hammer and pull the trigger back. Then put the hammer down on the chamber before making the check. If I do that the feeler gage of .0025 will fit on one side and .003 on the other. That's my new question. When I put the gage in the above are snug. I can slide up to .006 but they move the cyl back a tad. Nothing else will fit. Whets the correct way to put the gage in? Is that movement ok?

Bobster,

Niner #283

[DJ Niner]

I usually check B/C gap with everything at rest (not holding triger back), and holding cylinder as far to the rear as it will go with light hand pressure. The reason is that you can get a false reading (too small) because of the pressure of the cylinder hand acting on the rear of the cylinder as you hold the trigger to the rear. Some folks think simulating the moment of firing (holding trigger to rear) gives a more accurate reading, but as you noted, the cylinder will still move rearward if pressed. When the gun actually fires, the cylinder DOES move to the rear, at least briefly, so the MAXIMUM gap is the one I prefer to check.

It sounds as though your forcing cone is slightly out-of-true (.025 on one side, .003 on the other), but it's also possible that the cylinder is slightly off-center-axis in the frame opening, which would give the same effect. The maximum gap you reported as .006 sounds perfectly OK. In either case, the proof is in the pudding. If the gun shoots well, then I wouldn't worry about the gap at all. Only if it shoots very poorly with a shooter of known high skill with a revolver, would I begin to be concerned. And because the gap is not easily fixed (correctly) by the average gun-tinkerer, if there IS a problem, you should send it off to a full-blown revolver gunsmith, who is equipped to do all the checks and measures and specifically define the problem, so he/she knows exactly WHAT needs fixin'. :)

[Bobster]

Thanks again for the info. I shot it for the first time yesterday afternoon. It belches a bit more from the gap than I think it should(Orange flames to the right and left), but it accurate enough for what I am doing. (CC Handgun Instructors class.) With much practice over the next 2 months I will be equal to the Glock 17. And I expect to get better with the glock as well.

One thing I noticed is that this gun exaggerates all of my shooting technique faults. My groups are bigger, but its the same pulling and pushing of the trigger that makes the Glock groups larger as well.

I really like the wheel-gun.(My first) I intend to buy more as time and $ allow.

Bobster,

Niner #283

[JWP]

have a slimey/weasel [klintonista gun deal] model 29-2 manufactured in the 70s with no load gap at 0.003 and pushed back gap 0.005

a model 6o with 0.005/0.007 manufactured in the 90s

the 29 is very accurate the 60 less so with its 2" bbl but both function well

[jimmy]

Also, irregular (out of true) b/c gaps are not uncommon on S&W revolvers. A gap with .0025 on one side and .003 on the other side should be fine. There may be a slight variation from chamber to chamber, too, if the cylinder face isn't quite squared.

BTW, the most irregular gap I've seen was .005 on one side and .014 on the other. This was on my Model 624. I shipped it back to the factory service department, which set the barrel back to a nice even .003. :)

[Tony S45]

Thanks for the info in this thread. My 586 & 686 are .006 and .007 pushed back, respectively. Variations between sides and different cylinder holes are very slight (.001 or less).


As an alternative, my .357 Dan Wesson has .008 pushed back but is very similar sise to side and cylinder hole to hole!

[VN350X10]

Tony, your Dan Wesson should be set with a cyl. gap of .006" Did you lose the feeler guage that came with the gun? Thats the factory spec for every D.W. I've ever seen.

uncle albert

[Tony S45]

Uncle Albert

You are correct, Sir. However my Dan is a rare 3" FIXED barrel; therefore, no factory feeler guage because no barrel adjustment can be made! It is a very accurate gun that I use as one of my "house" guns and is clean/lubed but not shot very often. I can get nice small groups at 25yds. with this gun and it's combat accuracy when using it for Defensive Pistol BUG match was also excellent.

Should I be concerned about the excessive gap?

[VN350X10]

Tony, is it a .38 spl? Those are scarce!
I've only seen 1 of that model!
From the sound of things, I wouldn't worry about a thing with it.

uncle albert

[Tony S45]

Uncle Albert

Nope! .357 six shot but I shoot .38 130gr FMJ in it. A stainless steel gun made in Palmer, Mass about ten years ago. I replaced the tiny rear adj. site with a white outline Millett.

By the way, I should have included the fact that the gap is a snug .004 without pushing back the cylinder---a .004 variance when the cylinder is held back. Hmmmmm? I was full of confidence before but now you've got me worried. I'll call the Dan Wesson folks and see what they say and post a reply.

I know where there is another 3" FIXED barrel stainless gun just like mine for sale but I thought one was enough. I love the gun but it is heavy and bulky to carry concealed (legal in my State) and I'm about to build a L Frame 686 4" barrel for IDPA competition.

So many great guns: so little time and money!