This is sort of an aside and is currently the last post in the infamous 700 trigger thread on AR, but is has some comments on trigger design that are way above my level of knowledge but should be interesting to those of us who use them. Post follows:
posted 03-16-2003 11:44
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Plateau Hunter----
You said,
quote:
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Anything mechanical can malfunction.
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This is widely quoted and is certainly true....
But, (knew that was coming, huh?) When dealing with things stronger than you are, like guns, you want those failures to DIS-able the mechanizm, not activate it.
For those that looked at the patent drawings and see how the levers in an over-ride trigger work and think you're ready for something more complicated, Look into the chittlins of a S&W revolver and see how they're designed to "Fail Safe". If any part or combination of parts break, stick, bend or rusts the gun quits working. It *can't shoot*. It has "Failed Safe".
The best example of fail safe devices is air brakes. If a trailer or train car comes undone the air supply is interrupted and the brakes apply *from the lack of* compressed air and the thing stops instead of running away. George Westinghouse invented the air brake, I think.
The "Hammer the Hammer" design of the Iver Johnson DA revolver in 1898 was the first of the pocket revolvers to adopt fail safe designing. S&W and Colt soon followed suit.
There are two ways to make a fail safe trigger-- One transfers neccesary energy and one blocks that energy. S&W is a block design, Colt is a transfer.
The transfer bar fail safe has been adapted to Ruger SA and DA, D. Wesson, H&R, and others. The transfer system is much easier and cheaper to do than the complicated S&W-style blockers.
The odd thing is that the old DA Colt designs like the Match Targets, Det Spec/Agent/Cobra, Pythons and such are pure transfer bar designs but done in the most complicated manner possible. The transfer bars are driven by an ingenious likage unlike any other gun design but it's surprisingly tough and trouble free......until you drop in on the butt. That can lock the gun up...unable to fire, unable to open, and unable to unload.
The S&W is not near as fragile.
So yes. Mechanical things DO fail, but mechanical failures should bring cuss words and impatience, NOT blood and tears. There IS a better way.
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