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Does everyone measure a barrel length the same way?

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04 May 2006, 20:18
Snellstrom
Does everyone measure a barrel length the same way?
I don't think so!
My whole life I've always measured a barrels length by measuring from the obvious muzzle to the point where the barrel enters the reciever. This method may be wrong or right but it is how I've always done it, however it has come to my attention that some folks measure from muzzle to bolt face, some muzzle to bolt face minus the length of the cartridge brass, some say only measure the rifled portion of the barrel?
So what is the correct method?
Have I been off base for years or are these other guys whack jobs?
When I look at my factory rifles that have a published 22" barrel I get even more confused because none of the above methods hit it on the exact number.
Please let me know.
04 May 2006, 20:28
malm
quote:
Originally posted by Snellstrom:
I don't think so!
My whole life I've always measured a barrels length by measuring from the obvious muzzle to the point where the barrel enters the reciever. This method may be wrong or right but it is how I've always done it, however it has come to my attention that some folks measure from muzzle to bolt face, some muzzle to bolt face minus the length of the cartridge brass, some say only measure the rifled portion of the barrel?
So what is the correct method?
Have I been off base for years or are these other guys whack jobs?
When I look at my factory rifles that have a published 22" barrel I get even more confused because none of the above methods hit it on the exact number.
Please let me know.


According to THIS whack job, if you are dealing with the BATF then you probably want to measure from a closed bolt face to the muzzle. The factory measurement is from breech of barrel to the muzzle. For those reloaders and the rest of us who mistakenly refer to bore length as barrel length, it is from the base of the seated bullet to the muzzle. If you are only looking to impress your girl or boy friend, then you may measure it from the front of the receiver. Is that whacked enough? Big Grin

FWIW, If a customer wants a 26 inch barrel installed, I will ask them specifically if they mean barrel, or, bore. If it's barrel length, then it is 26" from breech to muzzle. If they want me to cut their shotgun barrel to 18" then I measure it from chamber mouth to muzzle.
04 May 2006, 21:41
vapodog
hey...one more.....and if it's chambered for the AI cartridge it's measured by the length of rifling in the barrel.....the chamber is not included.

I'd go by the BATF opinion and measure from closed bolt face to end of crown.


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04 May 2006, 23:18
ramrod340
quote:
if it's chambered for the AI cartridge it's measured by the length of rifling in the barrel

Thought that was the Rocky Gibbs method.


As usual just my $.02
Paul K
04 May 2006, 23:50
vapodog
quote:
Originally posted by ramrod340:
quote:
if it's chambered for the AI cartridge it's measured by the length of rifling in the barrel

Thought that was the Rocky Gibbs method.

Yes...you are correct but..... stir


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"Socialism is a philosophy of failure, the creed of ignorance, and the gospel of envy, its inherent virtue is the equal sharing of misery."
Winston Churchill
05 May 2006, 05:38
Snellstrom
So is it safe then to assume that the method to use would be from the closed bolt face ?
This is the method that the factory advertised barrel lengths are derived from?
05 May 2006, 07:15
malm
quote:
Originally posted by Snellstrom:
So is it safe then to assume that the method to use would be from the closed bolt face ?
This is the method that the factory advertised barrel lengths are derived from?


No, the factories usually measure from the breech end of the barrel, where the round goes in, to the muzzle, where the round comes out.
05 May 2006, 15:56
jeffeosso
i tend to keep things simple...

the people that would be enforcing the law are the ATF ... if I cut a barrel and there's a question, the ATF will be the one's who's judgement is final...

so, close the bolt, drop a rod down it, mark it, and measure from boltface to muzzle...

I think all (okay most) of the other ways of measuring barrel length are worthwhile... but they don't answer the LEGAL question..

jeffe


opinions vary band of bubbas and STC hunting Club

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the416AR, 458AR, 470AR, 500AR
What is an AR round? Case Drawings 416-458-470AR and 500AR.
476AR,
http://www.weaponsmith.com
05 May 2006, 21:10
Rick 0311
What jeffe said.

There are lots a ways to calculate the speed of your car, but the only one that really counts is the one the cops use! Smiler
06 May 2006, 03:41
bigbull
Our Firearm Laws in Canada measure barrel length from a closed breech to the muzzle.
bigbull
06 May 2006, 16:42
p dog shooter
Yep jsut as Rick0311 says. Close the breech and drop a rod down it.

But then I worked with a retired BATF agent for a while. (what a horses ASS.) We were measureing a shotgun that was legal with the rod measurement. But he said in all seriousness hell if we measure it from the action foward we can charge with with a short barrel shot gun.
We did it all the time in the BATF what ever it took.

From that time on I made sure all my barrels are plenty long. You might be right one way but spending thousands of dollars getting there wouldn't be anyfun.
09 May 2006, 08:23
nordrseta
quote:
So is it safe then to assume that the method to use would be from the closed bolt face? This is the method that the factory advertised barrel lengths are derived from?
Yes, except for revolvers, which are measure from the forcing cone to the muzzle (go figure).
10 May 2006, 02:07
<9.3x62>
quote:
Yes, except for revolvers, which are measure from the forcing cone to the muzzle (go figure).


True, but then to complicate things further, some states write their hunting laws such that revolver barrel length is measured from the firing pin to the muzzle...