barrel to cylinder gap?

[G.T. Smith]

Hey,
does anyone here know the recommended barrel to cylinder gap on a 65-4, 4". I don't have any kind of repair or maintenance manuals. I can barely see daylight through there and it seems nice and tight. Just curious.
thanks for any info.
peace,
gordon

 

[Kelly Green]

On a S&W revolver, the ideal barrel to cylinder gap is .006". A normal usable gap is .004" -- .010".

 

[bountyhunter]

+1 on Kelly's numbers.

I would add I have seen new SW guns as wide as .015.

 

[snuf]

+1 on Kelly's numbers.

I would add I have seen new SW guns as wide as .015.

.015

 

[rodell]

I have a 66-2 that is .012, and was that way from the factory. It spits debris all over the place with magnum loads.

Bob

 

[H Richard]

I have a couple with .002" gaps and they shoot great, just have to keep the cylinder face clean.

 

[G.T. Smith]

Alright,
Thanks for the info people. I checked the barrel to cylinder gap with a feeler gauge that only goes as low as .006. I had to hold back on the cylinder to get it to start. I am guessing that it is .004-.005 at the most. It doesn't throw any debris out when shooting magnum loads or anything but I was just curious. I can't believe that I bought that gun without the knowledge I have gained since joining this forum and can't detect any problems with the gun. I'm not usually that lucky. It is a police trade in and I suspect that it was carried a lot more than it was shot.
Again, thank ya'll.
Peace,
gordon

 

[ms]

You should measure the gap with the cylinder held back.

 

[rodell]

I have a 66-2 with .003" of endshake, but, .012 of cylinder gap. It would seem the only choice is to set back the barrel, right?

I'm the original owner, and, I've never abused this weapon. It has always spit something awful with magnum loads, but, the deer didn't notice. I did once blow a nice hole in the synthetic material on a rest, though.

I'm much more discerning now and want to fix it up.

 

[bountyhunter]

I have a 66-2 with .003" of endshake, but, .012 of cylinder gap. It would seem the only choice is to set back the barrel, right?

I'm the original owner, and, I've never abused this weapon. It has always spit something awful with magnum loads, but, the deer didn't notice. I did once blow a nice hold in a rest, though.

I'm much more discerning now and want to fix it up.

Did you measure the B/C gap with the cylinder pulled back? That is the actual gap when the endshake is removed.

The difference in muzzle velocity between a .008" gap and .012" gap is pretty trivial. If it really is too bad, SW can set the barrel in.

 

[rodell]

It isn't the velocity that bothers me, it is the spit. With magnum loads, you can feel the debris fly.

I did measure it with the cylinder pulled back.

 

[bountyhunter]

The only option is to have the barrel machined so it can be cranked in one more turn and have a proper clearance. I believe SW does this all the time. Problem may be, I have read multiple posts of people returning guns with B/C gaps in the .012" range and SW returned them as "in spec" without working on them. You may want to call SW and ask if they will fix it before mailing it in. Good luck.

 

[Bullet Bob]

No matter the cylinder gap, .357's are notorious for flinging out unburned powder, etc. with full magnum loads.

I remember years ago a gunwriter testing .357's from several manufacturers for a lengthy article; he wore one of those flip-up full face shields like welders sometimes wear (not the helmet type) for his bench testing.

In addition to the b/c gap, when dealing with stuff flying out at you, a person also has to be concerned with cylinder alignment with 6 or more charge holes, and smoothness and degree of the forcing cone. It's all good

 

[Chris Chatham]

Chris Chatham

While excess gap is not good, especially for the Guy next to you if you are on the firing line, It would appear that not enough gap is more of a problem, every day you read of people complaining of their revolvers binding up after a few shots. I believe this is caused by too little a gap and metal expansion from heating up after shooting, especiallly rapid fire.

 

[KLYDE]

All the guns I've sent into the Performance Center for rehab and work have come back spot on .003.

 

[ryxlyx]

Am I correct that it runs around $200 to have this done?

 

[Nick B]

All the guns I've sent into the Performance Center for rehab and work have come back spot on .003.

Does that include K and L frames ? Their website shows this B/C gap work only on N frame work .

 

[Nick B]

While excess gap is not good, especially for the Guy next to you if you are on the firing line, It would appear that not enough gap is more of a problem, every day you read of people complaining of their revolvers binding up after a few shots. I believe this is caused by too little a gap and metal expansion from heating up after shooting, especiallly rapid fire.

Yea but too little gap is a heck of a lot easier to correct than too much gap .

 

[Neumann]

Setting the barrel back is one part. First the crane is straightened and end play removed from the cylinder. The barrel is machined one turn of the threads and the forcing cone is refaced and rebored. $200 is pretty reasonable.

 

[KLYDE]

Does that include K and L frames ? Their website shows this B/C gap work only on N frame work .

Nick,
All K frames. (4) Many had high mileage and as a result endshake and other issues. Upon return I recieved a bag of old parts with each one. Hand, cylinder stops, Trigger pins etc. They even installed a new cylinder on my 64-2. Evidently upon rebuild they set the B/C gap which included having barrel turned. The guns were not specifically sent in for the B/C work. Each gun was like new upon return. Average price was 150-200 area. Back when I had this work done the wait time was 2-3 months. It is now in the area of 10-12.