Where to measure barrel length

[Cobrageezer]

Is the length of a barrel measured from the bolt face or the front end of the chamber. I've got a running arguement with a friend whose a LEO. I really want to be right. I say it is measured from the bolt face.:banghead:

 

[Tommygunn]

If you are refering to what the ATF uses to determine legal length for NFA longarms, it's boltface to end of barrel, IIRC.
If you mean what gunsmiths use ... I'm not a gunsmith.

 

[Just One Shot]

It would seem to me that the barrel length is measured from the chamber out. You don't count the cylinder length on a revolver why would you count the chamber length on a semi-auto?

 

[highorder]

The answer is, it depends.

What type of firearm are we discussing?

Usually boltface to muzzle, but revolver cylinders do not count.

 

[bigfatdave]

highorder has it. Like most things firearms-related (and all things firearms LAW related) it doesn't make a lot of sense.

Revolvers are measured by actual barrel length, auto-loading and single shot handguns from bolt face to crown, and as far as I know rifles and shotguns are measured from the bolt face as well.

You know measuring a few of your own (or your LEO buddy's) guns would have made the answer pretty obvious. Of course, just because someone happens to be employed as a LEO doesn't mean they know jack about firearms.

 

[buck460XVR]

It would seem to me that the barrel length is measured from the chamber out. You don't count the cylinder length on a revolver why would you count the chamber length on a semi-auto?

The answer is, it depends.

What type of firearm are we discussing?

Usually boltface to muzzle, but revolver cylinders do not count.

Sometimes revolver cylinders count also......this is from the Wisconsin Deer hunting Regs.

To be legal for deer, handguns must use center-fire cartridges of .22 caliber or
larger and have a 5½ inch minimum barrel, measured from the firing pin to the
muzzle with the action closed.

***********************************************************

 

[The Lone Haranguer]

I say it is measured from the bolt face.

Correct, for pistols, rifles and shotguns. (On autoloading pistols it is easiest, as a practical matter, to measure from the rear of the ejection port.) This will include the chamber. For revolvers, measure from the front of the cylinder to the muzzle.

 

[benEzra]

It would seem to me that the barrel length is measured from the chamber out. You don't count the cylinder length on a revolver why would you count the chamber length on a semi-auto?

Because in a semiauto, the chamber is part of the barrel, whereas in a revolver it's not.

In all firearms except revolvers, the barrel length is measured from the breechface to the muzzle. Revolvers are measured differently because the cylinder is simply not part of the barrel.

 

[Cobrageezer]

Sound's like I get to do the "Snake was right dance" We were aurguing about a carbine I have and Himself thinks it's to short! Yea Me. Thanks alot guys.

 

[bigfatdave]

from the Wisconsin Deer hunting Regs

WI in a rare case, is regulating the length of bullet-travel within the barrel, it actually makes more sense to me.
But that doesn't mean that it is a standard anywhere but in WI while talking about hunting handguns.

 

[The Lone Haranguer]

It would seem to me that the barrel length is measured from the chamber out.

But when the chamber is integral with the barrel, what do you use as your reference or starting point? The shoulder where the case neck abuts? The barrel throat? This is not consistent from firearm to firearm, sometimes not even the same model from the same maker. An eighth or even a sixteenth of an inch can make the difference between a legal 18" shotgun barrel and an illegal "sawed-off." A consistent measuring point that works on all firearms must be established.

 

[JohnBT]

I would measure that 18 inches from the firing pin, just to be safe. It's not how we measure it, it's how they measure it. Dry fire the gun and then drop the rod down the barrel and mark it.

John

 

[Just One Shot]

But when the chamber is integral with the barrel, what do you use as your reference or starting point? The shoulder where the case neck abuts? The barrel throat? This is not consistent from firearm to firearm, sometimes not even the same model from the same maker. An eighth or even a sixteenth of an inch can make the difference between a legal 18" shotgun barrel and an illegal "sawed-off." A consistent measuring point that works on all firearms must be established.

Well, there you have it. I guess you're never too old to learn.

 

[SSN Vet]

rules need to be simple and easy to measure.

drop a 16" dowel down your barel with the bolt closed.

if the dowel stands proud of the crown.... you be in trouble