nomenclature

[dryfarmer]

In the cylinder of my 686 357 there is a ring towards the front inside each shell hole what is the proper name for that ring

thanks

 

[bobelk99]

You likely will get better results by posting in
S&W Revolvers: 1980 to the Present

 

[s&wchad]

I believe that's called a lead (pronounced leed, not sure of the spelling). It's the step from the chamber to the throat.

 

[murphydog]

Also called a chamber shoulder, I think.

 

[dryfarmer]

its smaller then a bullet for what reason?

 

[Janitor]

I'm guessing you're right about it being the shoulder at the throat of the chamber. I think rounds like .45 acp would head space there.

Should be right about the end of the cartridge, and the bullet would 'rest' in the throat, just ahead of the forcing cone.

I *think* the leade is the inside of the forcing cone where the bullet is smushed (dang, I just love technical talk) down to bore diameter. That, or it's that final jump in space from the throat of the chamber to where the forcing cone starts doing it's dirty business.

 

[Tom K]

its smaller then a bullet for what reason?

When you say "bullet", do you mean the actual projectile within the brass case, or the entire cartridge? People often use the term "bullet" when they mean a complete round of ammunition.

Anyway, the smaller diameter area at the front of the cylinder chambers should be almost exactly the same size as the bullet. This allows the bullet to be supported on all sides (preventing skew, or wobble) as it crosses the cylinder gap from the chamber and into the forcing cone portion of the barrel.

The larger diameter area at the back of the cylinder chambers should be slightly larger than an unfired cartridge case, just enough to allow ready insertion. The bullet and the interior diameter of the case mouth are necessarily the same size. This is true for most modern centerfire ammunition - most rimfires and some older centerfire ammo use what's called a "heeled" bullet, where the part that sticks in the case is the same diameter as the ID of the case, but the part outside of the case is the same diameter as the OD of the case.

As an historical note, the S&W .44 Russian was the first commonly made ammunition of the modern configuration, with a constant diameter bullet the same size as the ID of the case, and stepped chambers in the gun's cylinder to accommodate it. The .44 Russian was lengthened to become the .44 Special, which was again lengthened to become the .44 Magnum.

 

[Mike McLellan]

Around here, we call them "bullet squeezers".