Ill outline it here for ease.
2016 Guide on Firearms Licensing Law. Available from
http://www.gov.uk
Page 22.
3.25 The manufacture, purchase, sale and possession of 3D printed firearms, ammunition or
their component parts is fully captured by the provisions in section 57(1) of the Firearms
Act 1968. The definition of firearm in the Act includes any component parts. 3D printed
firearms are subject to strict control in the following respects:
a. under section 1 of the 1968 Act, it is an offence for an individual to possess, purchase
or acquire any component part of a firearm without a certificate;
b. under section 3 of the 1968 Act, it is an offence for a person to manufacture or
possess for sale a component part of a firearm acting by way of trade or business; and
c. under section 5 of the 1968 Act, it is an offence for a person to possess, purchase,
acquire, manufacture, sell, transfer, possess for sale or transfer, or purchase or acquire
for sale or transfer, a component part of a prohibited weapon without the authority of
the Secretary of State for the Home Department or by Scottish Ministers in Scotland.
This section very clearly defines the fact that its illegal to possess, purchase,
acquire, manufacture, sell, transfer, possess for sale or transfer, or purchase or acquire
for sale or transfer, a 3D printed component part of a prohibited weapon without the authority of
the Secretary of State.
Then it states:
3.26 The expression “firearm” in the 1968 Act means a lethal barreled weapon of any
description, or component part of such weapon, from which any shot, bullet or other
missile can be discharged (see chapter 13 for more details on component parts). 3D
printed weapons are potentially lethal barreled weapons and must be viewed as such in
law. The method of manufacture is not material to this consideration.
This section clearly defines component parts as well as a lethal barreled weapon (complete gun) with the expression 'firearm'.
Its clearly states that the term 'firearm' in the 1968 act will mean both complete guns AND components.
It also clearly states that the method of manufacture is not material to this consideration. At no point does it state that the component part MUST come from a complete gun assembly.
3.3 Also states:
3.3 Note that the component parts of weapons falling under 5(1)(a), 5(1A)(a) or 5(1)(aba) are
also subject to section 5 controls (see also Chapter 13).
Now lets look at the Section5 guidance:
Weapons subject to general prohibition.
(1)A person commits an offence if he has in his possession, or purchases or acquires, or manufactures, sells or transfers—
2
(a)any firearm which is so designed or adapted that two or more missiles can be successively discharged without repeated pressure on the trigger;
(ab)any self-loading or pump-action rifle other than one which is chambered for .22 rim-fire cartridges,
4(aba)any 'firearm' which either has a barrel less than 30 centimeters in length or is less than 60 centimeters in length overall, other than an air weapon,
a muzzle-loading gun or a firearm designed as signalling apparatus.
So Section 5 (aba) clearly defines that a 'firearm' meaning complete gun or component under 60 centimeters (assembled weapon) or barrel component under 30cm
is illegal to posses, purchase, acquire, or manufacture, sell or transfer without Section 5 authority.
NOTE that section 5 (ab) states 'rifle', the word 'firearm' is not used. This is why component parts of Semi Auto centerfire rifles fall under Section 1 of the act.
So the legislation has established that a barrel under 12'' IS a Section5 aba component.
Now:
R v Clarke (F), 82 Cr App R 308, CA states that the component part of a prohibited weapon is itself a PROHIBITED WEAPON. Although there is no statutory definition, the Home Office Guidance to the Police at paragraph 13.70 states the following:
The term "component part" may be held to include (i) the barrel, chamber, cylinder, (ii) frame, body or receiver, (iii) breech, block, bolt or other mechanism for containing the charge at the rear of the chamber (iv), any other part of the firearm upon which the pressure caused by firing the weapon impinges directly. Magazines, sights and furniture are not considered component parts.
So the use of the term 'Prohibited Weapon' to define component parts as prohibited weapons in there own right is important. There is case law.
There is no statement to indicate whether the component part / prohibited weapon has to come from an existing weapon or be manufactured, as the act makes provision for the manufacture of parts its logical that they would be covered too.
3.26 states: The expression “firearm” in the 1968 Act means a lethal barreled weapon of any description, or COMPONENT part of such WEAPON, from which any shot, bullet or other missile can be discharged.
We already know that manufacture of Sec5 component parts is controlled.
The next chunk of legislation states the following:
7 Conversion not to affect classification.
(1)Any weapon which—
1(a)has at any time (whether before or after the passing of the Firearms (Amendment) Act 1997) been a weapon of a kind described in section 5(1) or (1A) of the principal Act (including any amendments to section 5(1) made under section 1(4) of this Act).
So Sec5 covers 5a, 5ab and 5aba and others. Any conversion of a prohibited weapon (as detailed in R v Clarke, a component part IS a prohibited weapon in itself) cannot be converted to another classification, it retains its original Section 5 status.
Therefore a Section5 aba component part (in this case a barrel under 12'') cannot be converted to Section1 or transferred to an individual who does not have authority under Section5 of the act to posses such an item.
As I stated earlier, it makes complete sense why the Home Office wants Breachers conversion work to be undertaken by a Sec5 authority, as the process involves the manufacture of a Sec5 aba component, what I'm amazed at is the conversion and subsequent transfer of a Sec5 aba component to Sec1.
That's my interpretation of the legislation. Ultimately and in the unlikely event this went to court it would be for a jury to decide. My personal opinion is that the email from the Home Office is incorrect, it contradicts the legislation and doesn't give permission to the Sec5 gunsmith to convert a Sec5 aba component to Sec1 for the purposes of transfer.
