It has been done many way. It can be done with any material that will reduce the noise of the two parts slamming into each other. You still want the transfer of energy though or you will lose power.
Some have used Orings cut into the face of the breach. Tony does this I believe. Ive also seen several other versions as well. I used a thin, flat rubber washer between the two. I got rid of most of the higher pitched sounds of the hammer strike and only lost maybe 20 fps.
Its not “floating”. Mine is attached to the breech with two tiny screws. I intended to try several different materials and then make a permenant one by gluing it to the breach face. You cant have it float because of the notch on the bottom that allows the hammer to re cock.
I put my breech in the lathe and turned a 1/16″ deep recess, 1/8″ wide in the back face of the breech and epoxied a 1/8″ diameter (material thickness) O ring. When it dried, I cut out the material that was blocking the notch. I’ve heard of others that cut an O ring in half and epoxied it to the face of the breech. I can’t remember if the idea was posted on here or the old TOG but it definately dampend the “slap” sound. I’m sure Tony does this mod if you don’t have the means to do it yourself. Happy Easter everyone.