I belive it is a set of plans for the Intensifier Trigger mod sold in the late 1980's
Here is some information taken from a chat room a while back.
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Anyone remember this device? The Intensifier Trigger mod???
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It was sold in the late 80's for the AK-47 and the Mini 14 originally.Then later on,that same idea bled to the M-11/9.
But for the M-11/9 they sell you a new hammer that is manufactured to fire one shot when the trigger is pulled,then one shot when the trigger is released.
It was BATF approved,it only shot once per movement of the trigger.Once back and the next when let go.
I had one on my Mini 14GB and it was the best.I pulled the trigger a few times and the mag was emptied at 750 rounds per minute.
It was a staple that you inserted between the primary and secondary sear to space it just enough so that when the trigger is pulled,it functions as normal,but,when the secondary caught,there is enough space when the trigger goes forward,the hammer releases again instead of the hammer hopping back to the primary.It does after the hammer obviously goes forward when the trigger is released,and fires a round and then resets to square one.This worked for the M1 Garand and the M-14 semi guns too.
The AK was almost exactly the same mod,a staple to space the primary and secondary sear.
On the M-11/9,it is different,so the hammer has its primary and secondary catch machined on,thus you were sent another hammer for about $39.99,but it would be well worth it.As the M-11/9 as a two shot trigger can empty the gun in a second,with its short bolt travel.
WHERE DID THIS DEVICE GO???I WANT ONE FOR THE AK,MINI 14 AND M-11/9!!!
I lost my Intensifier a long time ago,like in 92.I sold the Mini 14GB and want another one in stainless steel.My AK is ready to rock and so is the M-11/9.
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I think this is what is being sold on the e-bay link.
Ken RSA