FN/FAL - L1A1 firing pins

[Peter Laidler]

Just a very quick one....... Are the Commonwealth two piece firing pins interchangeable with tbe usual FN FAL strikers?

Did the FN FAL have a problem with broken firing pins as did the L1A1 series?

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[browningautorifle]

I had an early breech block without firing pin( a museum thing) and replaced it with a two piece from and FN C1 A1. Worked perfectly. Never heard of the early ones breaking. I think it was easier to produce in pieces, thus the change.

[Peter Laidler]

Thanks for that BAR. According to our paperwork, the original UK (and Canadian apparently.....) one piece firing pins were cracking and breaking across the shank, below the retaining pin groove. The problem was that the break wasn't linear or directly through, but sort of jagged across at an angle. This meant that in several examples, the lower pin part could and did rotate as the bolt was being pounded back and forth. There came a point when the longest part of the pin met up with the longest part of the head part (that couldn't rotate of course). That meant that there was firing pin protrusion and as a result there were 6 premature firings. In other words, unlocked breech explosions. I don't know if it was in 1959 but that's when the papers are dated.

To me, with my engineers hat on and going into a bit of basic metallurgy that I've remembered from uni days, plus the fact that it was happening in Canada and the UK (no mention of Lithgow.....), indicates a material or hardening/tempering problem. I would think that a two piece firing pin and head meant that you could have a tough head and a more resilient firing pin.

Anyone analysed the material. Just interest that's all but Armourers found the pins useful as drifts. Thanks again BAR.

Does anyone with an FAL used the L1A1 wo piece set-up

[FugWit2]

I have a metric FAL & it will not accept the inch pattern firing pins. Neither one-piece, not 2-piece will fit. (Nor will Izzy)
The difference seems to be that the metric FP has a steady taper along the entire length of the front end, the Inch has a stepped diameter & the step's shoulder will bind in the firing pin tunnel designed for a steady tapered version.

[Peter Laidler]

That's interesting fugwit and the reason I asked in the first place. Because one of the reports regarding the two poiece firing pin suggested that the change from one to two piece firing pin should coincide with a change in the breech block design so that the old one piece firing pin would not fit into a new style two-piece design breech block. I can only presume that this was to prevent anyone using old style one piece firing pins still in the system in the new style breech blocks.

Seems a LOT of trouble and expense to me........... I dont think we changed anyting so far as I'm aware - except the firing pin of course

What is interesting in this respect of course is that when we did the same sort of thing with the SA80 firing pin, we DID change the breech block so that the old firing pin wouldn't fit into the new breech block! Strange world isn't it

[FugWit2]

I think the difference we're seeing is between metric & Inch parts more than a change per se? I'm basing this on the fact that both 1 & 2 piece pins have the shapes depending on inch or metric version, not # of pieces.

My (metric) bolt came with a 1-piece FP & because of all the fuss here about snapping pins allowing runaway slamfires (No safety sear in the US, so the panic is pronounced, even though a safety sear would do nothing with a jammed & protruding pin induced slamfire) I finally found a 2-piece & swapped it just to be sure. Perhaps I did need to swap the bolt as well, but I was hoping to not need to re-headspace the rifle!

Now there is one interesting thing here that may just be coincidence, or it may indicate a "different" bolt was needed.
The metric 2-piece FP was longer than the metric 1-piece one! Not by a lot, but when I checked it installed with a FP protrusion gauge it was 5 thou over length. I checked which part was too long by comparing side-by-side with the 1-piece & it was the front section, the measurements of the rear section were identical. I reground the front tip, being careful to maintain the shape & there is no problem, but I did find the difference unexpected.