Forcing cone purpose and location


#1

Hello everyone,

Does the forcing cone stops the forward movement of the cartridge on its shoulder? (Like when a bottleneck cartridge headspaces off the shoulder - the forcing cone does that)
Thanks for any answers.

Bogdan


#2

The forcing cone allows the projectile to be gradually engaged by the rifling, thereby centering the projectile in the bore. All guns have some type of forcing cone.
The beveled area at the beginning of this revolver’s barrel is the forcing cone.


#3

Ok. And by asking its location when bottleneck cartridges are used, it shall be where the shoulder of the cartridges is, right?


#4

No, as Strelok pointed out, it is where the projectile engages the rifling. The term “forcing cone” is usually used in reference to revolvers; it’s more often called the leade in other types of firearms.

What you’re describing is simply the shoulder of the chamber.


#5

Aham. Now that you used the term ”lead” it makes sense. Thank you for the answer!


#6

Many revolvers made earlier than the 1920s did not have a barrel with the “forcing cone”. The “Leade” in a rifle chamber can be thought as a tapered area in the rifling which allows the fired bullet to get a bit of a running start before it contacts the rifling in the barrel. You seem to be asking about headspace, which refers to positioning of a cartridge in the chamber. For most (but not all) rimless rifle cartridges the headspace is determined by the shoulder of the cartridge case’s contact with the shoulder of the chamber. For rimmed cartridges, the headspace is controlled by the thickness of the rim.