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Hi all I have a quick question about measuring the barrel on an ar15 basically starting at the crown but where do I stop sorry if it's a stupid question.The ATF in America measure with the rifles bolt closed then run a rod down the barrel is that the same here? The reason I ask is I am having a barrel shortened to min length and want to stay on the right side of the law.

Hunter87 wrote:Hi all I have a quick question about measuring the barrel on an ar15 basically starting at the crown but where do I stop sorry if it's a stupid question.The ATF in America measure with the rifles bolt closed then run a rod down the barrel is that the same here? The reason I ask is I am having a barrel shortened to min length and want to stay on the right side of the law.

That's the easiest way, the barrel starts at point of ignition, ie, the primer/boltface. But, rather than cut it 300mm, cut it 310mm /12 1/2" to cover your arse

Swamp Donkey wrote:

Hunter87 wrote:Hi all I have a quick question about measuring the barrel on an ar15 basically starting at the crown but where do I stop sorry if it's a stupid question.The ATF in America measure with the rifles bolt closed then run a rod down the barrel is that the same here? The reason I ask is I am having a barrel shortened to min length and want to stay on the right side of the law.

That's the easiest way, the barrel starts at point of ignition, ie, the primer/boltface. But, rather than cut it 300mm, cut it 310mm /12 1/2" to cover your arse

Awesome thanks for the swift response swamp donkey much appreciated

Yup, measure from the bolt face in the closed position, I use a graduated brass rod as a reference and use a vernier as a depth gauge for a more precise measurement. I usually finish mine to an absolute minimum of 305,0mm measured to the inner most edge of the crown just in case someone wants to start quoting the 12"/12" rule (304,8mm)

Is that with the barrel hot or cold?

Ok,Ovenpa-what about 8" barrel with 4" muzzle break ,tig welded.Pass or troubles?-thnx,JB

polemass wrote:Ok,Ovenpa-what about 8" barrel with 4" muzzle break ,tig welded.Pass or troubles?-thnx,JB

It's my understanding you'd have to have a barrel blank (Unchambered) and cut it to 8", then weld the muzzle break and then chamber it.

You cannot cut down a pre-chambered barrel and then weld on to it as it becomes Sec5 when cut down. :(

If you take a shotgun barrel off the action, its no longer a firearm and just a component. Its length and the type of action would determine whether its sec 2, sec 1 or section 5. If it was cut to 18" it would be sect 1 if fitted to a lever action but sect 5 if fitted to a pump action. On its own it cannot be classified so you could cut it down and weld on bits etc

Not sure how this relates to a rifle barrel...................

For example - if you take a .45 rifle barrel off a receiver and cut it down to 6" then its just a componant ? If you refitted it to the rifle action it would be sec 5 but if you fitted it to a black powder revolver it would be sec 1.

Another example - you take a barrel blank - unchambered so its not a component. You cut it to 10" and its still not a component. You chamber it. What classification is it ?

As far as I can see, the barrel alone cannot be classified as a particular firearm until fitted to a particular firearm.

breacher wrote:If you take a shotgun barrel off the action, its no longer a firearm and just a component. Its length and the type of action would determine whether its sec 2, sec 1 or section 5. If it was cut to 18" it would be sect 1 if fitted to a lever action but sect 5 if fitted to a pump action. On its own it cannot be classified so you could cut it down and weld on bits etc

Not sure how this relates to a rifle barrel...................

For example - if you take a .45 rifle barrel off a receiver and cut it down to 6" then its just a componant ? If you refitted it to the rifle action it would be sec 5 but if you fitted it to a black powder revolver it would be sec 1.

As far as I can see, the barrel alone cannot be classified as a particular firearm until fitted to a particular firearm.

I thought it was specifically mentioned as an offence to shorten a shotgun barrel to less than 24" in the 1968 Firearms Act (unless you're a Registered Firearms Dealer).

Yes, you have to be a dealer and it has to be for a specific reason - replacing a defective part of the barrel and bringing it back up to 24".

That said, it says barrel of a shotgun, not shotgun barrel - subtle difference.

So, if you have a shotgun barrel - no shotgun, is there an offence for a non RFD to cut it down. I believe its already been held that barrels alone subject to less control ?