Hi,
Just need some advice on replacing the hop on my S&S Garand, as the current hop has rather obviously failed.......... As a newbie I need all the help I can get! 
First of all, is there any particular brand or supplier to go to for this replacement part? I'm not too rubbish with a screwdriver so am not overly scared of dismantling the casing. However all I know is that the donor gun is an M14, no idea what brand or manufacturer. Am hoping this is a standard part?
Is there anything I really should know about fitting and replacing this part? How much trouble am I likely to get myself in and how blue am I likely to turn the air while desperatley trying to force a square peg in a round hole? 
Thank you for your support............
First of all, take the gun apart as I told you on Saturday. There's no need to go inside the gearbox or take the crap off the outside of it... you'll see the crap... all levers and springs... you don't want to go there!
If you can, find a way to look down the barrel and adjust the hop, it should be visible in the barrel.
It is possible that the little bit of rubber that presses against the hop rubber is squashed flat or missing. If that's the case a good replacement is a small piece of the tube inside a bic biro.
i.e. don't buy anything until you've diagnosed the problem! It may not be a new hop unit!