From what I understand, one of the changes to the M-16 that occured in the '60s was the redesign/alteration of the buffer in the stock. Can somebody please explain this to me?

According to “The Complete AR-15/M16 Sourcebook” by Duncan Long, the buffer was changed in 1966 in order to lower the cyclic rate. “Colt engineers....devised a new buffer assembly that incorporated steel weights along with rubber pads inside it’s body rather than the hollow compression rings that had been used previously. This new assembly, coupled with a polyurethane bumper on the end of the buffer, lowered the cyclic rate of the rifle to 850rpm.... and had the added benefit of lowering the abuse on the action during recoil.  It also improved the chambering of cartridges due to the rebound of the polyurethane plastic off the rear of the buffer tube, making automatic fire more reliable.”

If you’re interested in the history and evolution of the AR-15/M-16 Duncan Long’s book is, in my opinion, a great source of information.

You referrign to an "edgewater" buffer?

[img]http://www.biggerhammer.net/ar15/buffers/Edgewtr1.jpg[/img]

I just happen to have one of these for my SP1. Really light.

[url]http://www.biggerhammer.net/ar15/buffers/[/url]