Legal answer with ref to proof

[ovenpaa]

The threaded section at the end of the barrel is integral to the barrel, so yes it is a consideration in my opinion.

[artiglio]

Another point to consider would be the likely invalidation of any insurance in an incident involving a firearm that was not proven.

[Sandgroper]

Another point to consider would be the likely invalidation of any insurance in an incident involving a firearm that was not proven.

As it isn't illegal to own or shoot a rifle that hasn't been through the Proof House, I can't see it being an issue unless there is a clause in the insurance that specifically excludes unproven firearms but I don't know for sure.

[@nd]

Re out of proof
I was lead to believe that as long as a firearm has not been altered (weakened) and it is being shot with the propellant it was proofed for it can never go out of proof. ??

[bradaz11]

The threaded section at the end of the barrel is integral to the barrel, so yes it is a consideration in my opinion.

But do they do any testing on it? Or just same as they do with unthreaded barrels

[ovenpaa]

A couple of test rounds and a visual inspection to the best of my knowledge.

[hobbesy]

Regina v Beatham tests the "unduly weakened" wording.

Reproof is required if the barrel is unduly weakened.

It was demonstrated to the court that removing a SUBSTANTIAL amount ( counter boring ) did not unduly weaken the barrel. So, I would submit that removing the much smaller amount when threading, would also not unduly weaken the barrel.

Things to bear in mind.......
R v Beatham did not specifically cover threading but counterboring.
Proofing is only required if selling or offering to sell the firearm - there is no offence of just possessing an out of proof firearm for your own use.

Where does it say I need to have it proofed before I sell it on please?

Hobbesy

[breacher]

The Proof Act states it clearly.

It makes it an offence to sell, exchange, expose or keep for sale, or export, or keep for exportation,
or to attempt to sell, exchange or export, or to pawn or pledge, or attempt to pawn or
pledge, or to take in pawn or pledge, an arm, the barrels of which are not duly proved and
marked as proved, (Section 108 and 109 of the 1868 Act);

[Odd Job]

I recently heard within the trade of a sound moderator ending half way down the range on the third shot with a centre-fire rifle. Upon inspection it had taken the threaded section of the barrel with it which would suggest to me it had been 'materially weakened' .

Would proof even look at that? They are worried about the barrels integrity not the quality of machining to add a mod

Exactly. Both the barrel and the moderator would pass proof individually, but the combination of the two resulted in failure.
Could be the threads on the barrel, could be the moderator. Could be that the barrel threads go down range with the moderator, could be that a portion of the moderator goes down range with the bullet trapped inside. Or it could be that the bullet damages the moderator and comes out at an angle and goes down range to the side.

In all cases I submit to you the damage is no less or no worse, whether there was a proof mark or not. I suspect (as I said in another thread) that all these failures involving moderators or pieces thereof going down range have nothing to do with weaknesses in either part, but more to do with misalignment of one part to another.

It could even be that a moderator with loose individual baffles (such as an ASE Utra dual rimfire) could be improperly assembled by the user after cleaning and result in an obstructed moderator.

I remain very sceptical about the requirement to reproof a threaded barrel for those reasons.

[Sandgroper]

I recently heard within the trade of a sound moderator ending half way down the range on the third shot with a centre-fire rifle. Upon inspection it had taken the threaded section of the barrel with it which would suggest to me it had been 'materially weakened' .

Would proof even look at that? They are worried about the barrels integrity not the quality of machining to add a mod

Exactly. Both the barrel and the moderator would pass proof individually, but the combination of the two resulted in failure.
Could be the threads on the barrel, could be the moderator. Could be that the barrel threads go down range with the moderator, could be that a portion of the moderator goes down range with the bullet trapped inside. Or it could be that the bullet damages the moderator and comes out at an angle and goes down range to the side.

In all cases I submit to you the damage is no less or no worse, whether there was a proof mark or not. I suspect (as I said in another thread) that all these failures involving moderators or pieces thereof going down range have nothing to do with weaknesses in either part, but more to do with misalignment of one part to another.

It could even be that a moderator with loose individual baffles (such as an ASE Utra dual rimfire) could be improperly assembled by the user after cleaning and result in an obstructed moderator.

I remain very sceptical about the requirement to reproof a threaded barrel for those reasons.

That's without throwing proof house mistakes into the mix - http://jacksonrifles.com/zz-silencers/proofwarning.htm

Edit: Forgot to add even though it's an old warning a mate of mine got sold a new 223 Moderator that was proofed for 308 Win about 18 months ago - fortunately he hadn't fired it on his 308 Howa when he discovered it. The RFD was not happy, replaced the mod and was going to chase up the Proof House - I'll need to ask if he heard any more about it...