Although I've found plenty of things to do around the house with the free time created by COVID-19 restrictions, I found something I thought a bit surprising when fiddling with my 3 revolvers and checking their barrel/cylinder gap measured with a feeler gage.

S&W 500 Mag Performance Center - about 0.0055"
S&W 500 Mag 8.375" barrel - slightly tighter at 0.005", probably 3x as many rounds through it as the PC, maybe 1000 rds
Then the surprise
Ruger SP101 .357 Mag - 0.004"

All of those check out, good job. I would wager 99% of revolver owners couldn’t tell you there B/C gap, and most probably don’t even know what a feeler gauge is.

Truer words were never spoken....

Decades ago I could tell you BC gap on all my revolvers. Today? No way. I am more concerned with how they shoot.

Kevin

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Unshared knowledge is wasted.

I tend to agree, as I‘ve not checked most of my revolvers.

Yet, I did find some measurements in my old notes so, I have gone down this road, too. Guilty, as charged.

Cylinder End Shake

Smith & Wesson 629-3, SN BHF58xx
.0035”

Smith & Wesson 627-0, SN BFP79xx
.002”

Ruger Super Blackhawk, SN 20xx
.0055”

Ruger Security Six, SN 155-296xx
003”

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Veteran Paratrooper, '86-'90

I usually have a new shooter about 5 minutes before I capture the B/C gap, the SA pull, the DA pull, and the cylinder diameters in my spreadsheet. I often do a slugging of the barrel as well.

Those numbers tell me what I have and suggest what bullet/powder combo to start with. After that, group size and velocity tell me all I need.

Using dumb luck to match the gun and ammo has not proven to work for me. Maybe I'm just unlucky.

Prescut

I don't check mine unless I have problems. I think that I have only had to check one, and even then the gap was within spec.

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Only a cold warrior

I have never had any problems with any of my revolvers, so need for me to check the headspace, even so, end shake, and or backlighting will give a quick indication of a problem. However, i do know what my Dan Wesson 715, and 722 are set to....

Our M460 carry is .0065".
Hopefully I'll be measuring another 460 this week.

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Have Fun/Stay Safe