As our readers know, the self-loading rifle (SLR) and its select fire automatic rifle (AR) brother were designed to fire the 7.62x51mm NATO cartridge.  But, what to do when you want to train your troops in the use of their weapons without actually shooting anyone?  You use blank cartridges that don't shoot a projectile.

 

Blank cartridges come in one of two kinds: (1) the U.S. M82 that has a formed "nose" to aid in feeding and is sealed with a waxed paper wad, or (2) the crimped brase case that's dipped in sealant to prevent entry of water into the case and soak the powder.

 

In order to make the SLR or AR function as it was designed with blanks, you must use a blank fire adapter (BFA).  The BFA is a plug that is inserted into the muzzle of the rifle that traps enough of the gases from the burning propellant to work the action as if it was firing live ammunition.  In some cases, the restrictor tube is large and long enough to trap enough gas pressure to work the action and its diameter is narrow enough to allow the excess pressure to bleed past the restrictor tube to the surrounding air.  In another case, the restrictor tube blocks the bore and has an orifice hole down its center.  The hole is large enough to trap enough gas pressure to work the action and the hole allows the excess pressure to bleed off to the surrounding air.  The various Commonwealth countries -- Australia, Britain, and Canada -- designed different versions of BFA that used both methods.

 

In 1956, the Commonwealth countries decided to standardize the inch-pattern version of the FAL rifle, semi-automatic fire only, as their basic infantry arm.  Australia and Canada also decided to adopt a heavy barrel, selective-fire automatic rifle version of the FAL similar to the metric pattern FALO.  Britain did not adopt the automatic rifle, but decided to adopt a 7.62 NATO conversion of the .303 caliber World War 2 Bren light machine gun instead.  One of the first items addressed by the joint Rifle Steering Committee was a working BFA for training purposes.  The one rule set forth by the RSC was there had to be interchangeability between the Commonwealth rifle parts.  That is, the part had to have the same fit and function, but the form could be made to the individual user's specifications.  Canada came up with a very simple BFA made of stamped steel.  Britain adopted the Canadian pattern at first, but redesigned it to a more robust cast steel version.  Australia adopted a machined steel variant of BFA. 

 

Thanks to our resident Commonwealth FAL guru, Kevin Adams in New Zealand, and your author, we'll lead you through the development of the BFA starting with Australia, followed by the UK (Britain), and ending with Canada.  As we work our way through the various designs, we will see interesting solutions to the problem of getting the various rifles to operate with blanks.

 

A note about Australian designations:  Australia uses two type classifications for ordnance and related accessories.  One is for Australian-built designs and the other is for foreign designs built in Australia.

 

If the design originated in Australia, it is given an "F" designation followed by a number.  Alterations to the basic design are followed by an "A" and a number that corresponds to the number of revisions to the basic design.  If the designation is Widget, F1A1, it indicates the first Australian-produced Widget with one alteration to the basic design.

 

If the design originated outside of Australia, it uses the UK designation pattern.  It is given an "L" for land service, followed by a number, and an "A" for alteration and a number that corresponds to revisions to the basic design.  If the designation is Gizmo, L2A3, it indicates UK origin with three alterations to the basic design.

 

Australian Defence Forces designated threee different BFA's for the various SLR's and AR's built by Small Arms Factory, Lithgow, New South Wales. 

 

 

F1 -- basic cast and machined steel design for L1A1 SLR and L2A1 AR.

F1 (Special) -- redesign of F1 BFA to fit the different flash eliminator of the L1A1-F1 SLR sold to Papua New Guinea and Hong Kong.

F2(?) -- a design for L2A1 rifles with a specialized recoil reducer (or muzzle brake/compensator) made for Malaya and Trinidad.

 

 

 

 

Continued in Part 2