Barrel Length Question

[Guest msparks]

How is the barrel length computed?

To me the barrel starts where the bullet comes in contact with the rifling.

I measure my XD45C which is supposed to be 4" and you really only get about 2 3/4" of rifling.

Is the barrel length computed the same on revolvers as they are on pistols? What about long guns?

What's really confusing is the barrel would be longer or shorter depending on caliber. For instance you would get more rifling in a 9mm than you would in a 45acp.

Anyhow thanks for any comment, it's just something I always wondered about.

[Guest nysos]

In revolvers, the barrel is just that, the barrel you see is what is measured. The cylinder is not considered part of the barrel since they are separate pieces.

In semi-auto's since the chamber is a fixed part of the barrel, it is computed in barrel length. So a 3" barrel in a semi auto, vs a 3" barrel in a revolver, the revolver technically has the longer barrel.

[1gewehr]

According to ATF, for legal purposes for rifles and shotguns, you stick a rod down the barrel with the breech closed. The rod should be firmly against the breech block, bolt, etc. The length of the rod inside the barrel, including any permanently-fixed muzzle devices, is the length of the barrel.

For handguns, there is no need to have a legal method of determining barrel length as there are no laws requiring it. The industry standard is as mentioned above. And yes, revolvers have a longer effective barrel length than an automatic.

[quietguy]

For handguns, there is no need to have a legal method of determining barrel length as there are no laws requiring it. The industry standard is as mentioned above. And yes, revolvers have a longer effective barrel length than an automatic.

I don't think that is 100% true. Doesn't Tennessee define a handgun as having less than a 12" barrel?

[JAB]

For handguns, there is no need to have a legal method of determining barrel length as there are no laws requiring it.

Actually, while there is some indication that the regulation may have changed this year, a minimum barrel length of four inches was [at least up through last year] a requirement for a handgun to be legally used for hunting in Tennessee. That was actually the one reason I chose to buy a used Taurus 66 over a used Ruger Security Six. Both were supposed to have 4 inch barrels and I would have preferred the Ruger but the barrel on the Security Six measured out to be just under 4 inches while the Taurus measured out at a true four inches. Since there was a possibility I might want to use it for a backup for hunting I didn't want to take any chances.

Further, while the cylinder length is not included in barrel length, my understanding is that the length of a revolver barrel is measured from the front (face) of the cylinder. Is that not correct?