Why is a Metric FAL "Metric"? Type X receiver?


November 2, 2007, 07:31 PM
Simple question I am sure. I find thousands of references to metric and inch FALs, but no where have I been able to find a simple explanation of WHAT is metric and inch.

And also this Type I II III receiver business. Again, thousands of references but nothing concise about what that means.

Tell me please :)

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AZ Jeff
November 2, 2007, 07:42 PM
FAL's fall into two basic categories: "metric" and "inch pattern".

Metric FAL's for the most part are built to specifications set forth by FN when they originally designed the weapon. Various parts may have been updated/revised over time, but the basic dimensions and tolerances were established by FN using the metric system.

In the early 1950's, when the British Commonwealth decided to select the FAL as their next generation rifle, a "Rifle Steering Committee" was established with representatives from Britain, Canada, and Australia. The RSC took FN's design, and converted the drawings from metric to inch dimensions. They revised a number of dimensions minorly, and they altered some of the tolerances on the basic dimensions as well. They also changed most of the threads on the various parts to imperial thread from metric thread. The end result was a rifle that was a "close copy" of a FAL as made by FN or it's liscensee's, but not an EXACT copy.

Some parts WILL interchange between metric and inch pattern FAL's, but there are a number of parts that will NOT, especially anything with threads involved.

For more details on this, see R. Blake Stevens series on the FAL, available from Collector Grade Publications.

AZ Jeff
November 2, 2007, 07:48 PM
Type, I, II, and III receivers refer to the external geometry of the reciever. Blake Stevens books show good pictures of the three types, but here is a verbal summary:

Type I--the original FAL receiver, with lightening cuts in the outside surfaces of the magazine will, and along the longitudinal surfaces of the upper receiver where it mates with the lower. Manufactured by machining a forging to achieve final shape. Used only on early FAL's

Type II--same as Type I, but with added "lugs" in the sides of the upper reciever where the latching lug is located at the rear that ties the upper to the lower reciever. Same construction.

Type III--simplified, cost reduced design. Eliminated lightening cuts in mag well sides, eliminated cuts along longitudinal surfaces. Manufactured by taking an investment casting and doing secondary machining to achieve final shape. Used on FAL's made from the mid-1980's on....

November 2, 2007, 09:52 PM

November 2, 2007, 10:47 PM
Wow! Thanks, I knew I could count on you guys.

November 3, 2007, 01:01 AM
the threading is the same between inch and metric guns as metric receivers and inch barrels will mate up. The main issue is the inch guns are a major redesign of the sights, lower receiver and such. They just changed the drawing specs on the things to inch,same threads just differant stated in inch vs metric is all.

November 3, 2007, 02:03 AM
Alex, What is meters vs. yards for the rear sight calibration?


November 3, 2007, 02:40 AM
I always forget to phrase my answer as a question...




November 3, 2007, 03:25 PM
i'm still confused on the differences between a para FAL, and a regular FAL.

Father Knows Best
November 3, 2007, 03:50 PM
FAL (carbine):

Para FAL:

Those are DSA SA58's, actually, but they are close copies of the FN FAL. The main differences are the butt stocks and rear sights.

November 3, 2007, 03:55 PM
I have an inch pattern L1A1 FAL type rifle. Inch magazines are different from the metric equivelant. The lower receiver is machined different at the front where the mags front catch is too. Supposidly metric mags will work in an inch rifle, but inch mags won't fit a metric rifle.

My experience with metric mags is that they "sort of" work in an inch gun. May fall out under recoil. Might be my rifle. The inch pattern mags have a pronounced spot welded front hook on the mag body, and the metric mags have a much smaller front hook thats punched from the mag bodys sheet metal.

As near as I know, a para FAL has a steel folding stock, and is a bit shorter. Can't say for sure because I've never seen one in real life.

Bwana John
November 3, 2007, 05:10 PM
The metric has inch threads:evil:

November 3, 2007, 10:10 PM

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