Cylinder Gap ?

[hylander]

One last Vaquero question.
How much cylinder gap is acceptable.
I am measuring .006 on brand new guns.

[DougGuy]

That's fine, won't hurt a thing.

[lefty o]

.006 is fine.

[Outpost75]

0.006 is Mean Assembly Tolerance for a revolver of caliber in which lead bullets are mostly used.

[hylander]

OK, I measured both models we have in stock.
One I can a tight .007 and the other an easy .006
These are both SS, we have a blue model .004

[Ragnarok]

Too tight a gap and turning the cylinder can get 'crunchy' with dirty loads that leave some unburned powder or especially with black powder

[hylander]

Out of curiosity, what does some of your guys Ruger's measure ?

[Outpost75]

When I attended the Ruger Armorer's School in the 1980s, our instructor, Mike Moore explained that in .357 revolvers and other calibers which were expected to be used with JACKETED bullet service ammunition, that the build spec. was to "Pass .002" and "Hold 0.006" with the rear gage in place, BEFORE proofing.

After proof firing the gun had to "Pass .002" and "Hold 0.008" with end shake not to exceed 0.0015"

.38 Special revolvers were presumed to be used with lead bullet ammunition and the "Pass" spec with rear gage in place was 0.003". Some contract revolvers, notably the French 9mms, were produced to tighter specs, being intended for use with jacketed ammunition only. The French spec was "0.05mm Pass" (0.002") and "0.15mm Hold" (.006"). Those gages were also used for US Customs revolvers intended for use with the 110-grain +P+ Olin Q4070 load, US Marine Embassy Guards, GSA FPS, Postal Inspectors and other US Gov't customers.

[hylander]

We have a Blued model that measures under .006
Checking with Calipers the Throats measure .451 and the cylinders .481
How do these measurements sound ?
I put this one on hold for myself

[paul h]

A caliper is not an accurate measurement of the throat or chamber, you need to use a pin gauge or a small hole gauge in concert with a micrometer.

I prefer my cylinder gap to be between 2 and 5 thou, under 6 wouldn't bother me. If you're going to run mild and hence somewhat dirtier loads exclusively then more gap is better than less. If you run higher pressure loads, the gap shouldn't give you an issue of hanging up the cylinder.

[mj2evans]

Dan Wesson use to (no idea about now) pack a 0.006" feeler gauge with their revolvers for you to set cylinder gap if/when you change barrels. I know I checked my Ruger bisley when I first got it and it was right around 0.006 in 45 Colt and has shown very good accuracy so far.

[hylander]

Found one I am going to purchase.
Less than .006 on all chambers.

[robg]

my 686 1980 model had .004 ,i miss that gun.won a turkey with it one year.

[Hickory]

Out of curiosity, what does some of your guys Ruger's measure ?

I have a Ruger single-six Bisley 32 magnum that has less than 0.001 barrel/cylinder gap.

I have showed it to several people who said it was not possible for it to leave the factory with such a narrow gap, but I have one, and it does not bind-up at all even after several hundred rounds through it,

[cajun shooter]

If you shoot nothing but clean loads such as using powders like Clays then a smaller gap will work. If you shoot a lot and the gun becomes dirty then .004 is too small.
I shoot nothing but BP loads in my SASS matches and they are full case loads of 2F, I've found that .007 is the best to use.
I attended many Armorer schools in the eighties and 5 S&W schools were in those. .004-.006 was the range used when we built the model 65 and 686 revolvers.
The Ruger School was my best as far as seeing what punishment a revolver could take and still function.