Last weekend I came up with an idea for my Tapco T6 collapsible stock for reducing the recoil on my Saiga .308. It involved a $2.00 coil spring and a 45 cent roll pin, and some time. The spring is 4.75" x 1" dia. The roll pin is 1/4".
Drilled a hole from top to bottom inside the very rear of the butt stock, vertical, for the roll pin. This provides the stop for the spring.
I cut out the 5th hole to an elongated form to allow for some "travel". I like the 5th hole position for my self. The rifle can still be moved to the 6th (last most extended position) or to another position. I do not think you can get much past hole 4 unless you put in another spring, or completely take this out (preferred).
When shot, the center tube now has room (slot) to slide inside the receiving butt stock rear piece and has resistance against the spring right away. I have tried it doing some bench rest trails, on handloads Friday (9-11-09) and it has performed spectacular, reducing the felt recoil by a significant amount. The fire is single shot and it gets back on target a bit quicker. Reminds me of shooting the 7.62 x 39 Soviet round, and not the .308
Very easy to do, and really lessens the felt recoil on the .308.