Valmet Recoil Buffer Installation
Special thanks to B. Wood of the former Valmet Weapons Club for this information
Recoil buffers are used to soften the rearward forces of the AK series bolt on the receiver. Quite a few rifles have factory installed buffers such as the Heckler & Koch MP-5 A3 retractable stock, and the Colt AR-15.
Buffertech Buffer
BlackJack Buffer
Blackjack Buffer
First brand I am aware of is the most common. BufferTech buffers are available from numerous sources, and can be ordered directly. Cost of the Buffertech buffer is higher than the Blackjack buffer due to a higher level of molding. Appearance of the Buffertech buffer is typically an off color white (natural) color.
The second brand I am aware of is from Blackjack Buffers. BlackjackBuffers can be ordered directly from Randy via email. Cost of the Blackjack buffers is lower than theBuffertech brand, and actually a bit easier to install. I want to thank Randy from Blackjack for sending the samples for testing and this page.
Installing the buffers is actually pretty easy. First off.....Make sure your gun is UNLOADED. Keep the muzzle pointed in a safe direction at all times. (Yes I know, all of us know this, but a reminder is always a good thing). Besides...I am poor and cannot afford to be sued. *LOL*
Please refer to the Field Stripping Your Valmet section on the front page of this site. After you get your trusty AK type rifle field stripped, we will start. 
On many rifles the Blackjack buffer will simply slide over the recoil spring. Push the buffer all the way to the rear of the recoil spring from the front.
On a number of rifles the recoil spring will need to be disassembled to install the buffer. It is easy to do. Be CAREFULL when taking down the recoil spring. It has substantial pressure and hurt someone if you are careless. Always keep firm control of the recoil spring.
Next step.
Pull back the recoil spring.
Hold firmly.
Slide Back recoil spring stop.
On many rifles this is slightly different.
Basic concept is still the same.
Remove Recoil Spring Stop.
Gently release pressure on the recoil spring.
Remove the recoil spring from the recoil spring guide.
Slide the buffer back over the recoil spring guide. Push all the way to the rear.
Next step is to reassemble the recoil spring. Simply reverse the above steps.
Buffertech on top.
Blackjack on the bottom.
Note the position of the buffer.
After the buffer is installed, reassemble the recoil spring asssembly in your rifle. Leave the top cover off. Check out how the buffer works by hand cycling the bolt. BufferTech buffers are thicker than the Blackjack buffers. I have heard of a couple of cases where the BufferTech buffers have been too thick for the rifle to function correctly. 
Blackjack buffer installed on a Very old Model 62/s!
BufferTech buffer installed on a Valmet 76.