Cylinder sense . . .

[6hold]

Learning all the time . . . yup, just found out that the line in the cylinder of a revolver, nearer the barrel end, is not just the demarcation point of where bullet and casing depart company but it is also bored out to different tolerances. The cylinder is bored out to approximate case diameter and the bullet side is bored out to approximate the bullet diameter. All these years I wondered why I couldn’t clean the cylinder bore better in that area (the step). I always thought that the “forcing cone” on the barrel was the only area that aligned the bullet with the barrel. I'm willing to bet that the early revolver cylinders where bored straight through (no step). What other little gems are coming my way today?

.

Looking through a normal
chamber you can see the
"step"

Cut-Away cylinder
Note the "step" where it goes
from cartridge diameter to
bullet diameter​

.

 

[Pilgrim]

I'm not sure all cylinders are done that way. I've got several that I don't think are. I'll have to check them later.

 

[one-eyed Jack]

What revolver do you have? Jack.

 

[Pilgrim]

What revolver do you have? Jack.

off the top of my head:

SW332 .32mag
SW66 .357mag
SW629 .44mag
SW28 .357mag
SW Victory .38s&W
Colt 1917 .45
Colt New Police .32
DW K22 .22lr
DW supermax 357max
Taurus K22
Iver Johnson Safety Hammer .38s&W
Ruger Blackhawk .41
Ruger New Vaquero .45
Webley MkVI

probably others, I'd have to check my list

 

[6hold]

I'm not sure all cylinders are done that way. I've got several that I don't think are. I'll have to check them later.

Pilgrim ~ I'd be interested in your findings, I too will check the very few other revolvers I have. My Ruger black powder surely must have a single bore size.

 

[Pilgrim]

I checked the Smiths last night and they do have the 'ring'. I'll check the Colts and other tonight and see. Something in my mind says the at least one of the Colts doesn't.

I could be wrong...have been before.

 

[RKG]

Note that any older revolvers for "outside lubricated" cartridges (such as .44 American) will not have the chamber to bore step, for the reason that slug diameter and case diameter are the same. (Like a .22 LR.)

See http://en.wikipedia.org/wiki/Heeled_bullet

 

[6hold]

Note that any older revolvers for "outside lubricated" cartridges (such as .44 American) will not have the chamber to bore step, for the reason that slug diameter and case diameter are the same. (Like a .22 LR.)

See http://en.wikipedia.org/wiki/Heeled_bullet

RKG, thanks for the info and link. I'm posting just a short part of the info from that link, if you don't mind. They explain more about how different cartridges names came about also.

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"(Like a .22 LR.)"​

Cartridges evolved from heeled bullet designs
To convert a heeled bullet cartridge to a non-heeled design, it was necessary to either enlarge the case diameter, or shrink the bullet and bore diameter. Examples of both choices can be found, but some of the more evident and confusing examples are cases where the bullet diameter was reduced. Many shooters wonder why a .38 caliber firearm actually shoots bullets of diameter .357 inches, and a .44 caliber firearm shoots .429 inch diameter bullets. In both of these cases, the name of the caliber derives from older heeled-bullet designs, and the name was kept even when the bullet was shrunk to fit inside the case. The .38 S&W cartridge, for example, dates to 1877 and has a nominal outside case diameter of .380 inches, while the inside of the case is .357 inches. Older .38 caliber cartridges, like the .38 Long Colt, did use a heeled bullet, so rather than create a new ".35" or ".36 caliber", Smith and Wesson kept the designation ".38" even though it no longer accurately reflected the bore diameter. The later .38 Special continued the trend, and even automatic pistol cartridges like the .38 Super and .380 ACP retained the .38 caliber designation, even though they were .357s. This continued until 1935 and the introduction of the .38 Special-based .357 Magnum cartridge. The newer (1956) .44 Magnum, however, retained the designation of its parent .44 Special cartridge, even though it fired a .429 inch bullet. The legacy of heeled bullets is the cause of confusion among many shooting enthusiasts over the actual physical diameters of the bullets they fire in their guns.
Retrieved from "http://en.wikipedia.org/wiki/Heeled_bullet"
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[RKG]

Your welcome.

Dipping further into the "Useless Information" reservoir (it is quite deep): you should be able to find some articles and grievances concerning revolvers chambered for .45 AR/.45 ACP. Older revolvers had the chamber to slug-diameter step, which allowed .45 ACP ammo to be fired without half-moon clips -- that is to say, headspacing on the mouth of the case (as they do in autos) -- with the absence of the half-moon affecting only ejection of empties. Apparently, modern revolvers chambered for the same round are cylinder-bored, headspacing on the rim and requiring the use of half- or full-moon clips. I'm guessing this is done to save on manufacturing costs.

As for firing .38 Spl rounds in a .357 chamber, I've done it for years without a problem. There are two theoretical issues. One is that combustion crap will accumulate at the transition point. This is true, but it comes out with ordinary cleaning. The other issue is that you'll get flame cutting that will later affect use of full-length .357 rounds. This I have found to be false.

 

[Pilgrim]

Well, I checked all my stuff and they all have the 'ring', except for my Webley and of course my cap and balls.

I guess it is the 'normal' way to do it as mentioned above.

 

[6hold]

Well, I checked all my stuff and they all have the 'ring', except for my Webley and of course my cap and balls.

I guess it is the 'normal' way to do it as mentioned above.

Thanks for checking Pilgrim, that can be a pain to do with all the revolvers you have. Mine check out the same except of course the 22. Now I can stop trying to clean out the step that I thought was buildup!

PS ~ Pilgrim, you're not “THE” Pilgrim that John Wayne is always alluding to, are you?