I have floated many handi forends and the trick to make it work is to keep the forend from binding between the barrel and receiver, the so-called O-ring trick will cause the forend to pitch down in the front because the contact point with the forend shoe and receiver is always the same position, when adding an o-ring or any thing else between the barrel and forend at the barrel lug point will cause the forend to be pitched down, as you tighten the attaching screw this causes the forend to try and level out causing a binding action between the foren, barrel, and action which will result in the barrel being pulled in one direction as it heats up when being fired.
The correct way to float the forend is to remove the forend from the gun and make sure the gun locks up tight without a forend on it. If the barrel does not lock up tight without a forend this problem must be fixed before continuing, once you have determined the gun locks up tight with out the forend remove the forend shoe from the rear of the forend and fill the screw holes with wooden dowels and 2-part epoxy, sand the barrel channel slightly oversized using a wooden dowel with a piece of sandpaper wrapped around it.
Next wrap a piece of electricians tape around the barrel at the points where the front and rear of the forend will contact the barrel, apply mold release, paste wax, light oil, etc. to the barrel lug and a small area around the barrel lug ( anything to keep epoxy from sticking to the metal ).
Apply a fair amount of 2-part epoxy to the flange area of the barrel lug and or to the forend attaching hole recessed area, install the forend onto the gun, attach the forend with the attaching screw and tighten the screw just snug, this will cause the epoxy to contact the wood and the barrel and also the tapered head of the screw will cause the barrel lug to align in the center of the hole in the forend, after the epoxy has set up remove the forend and make sure the epoxy has made a nice bed in the forend hole recessed area to allow only the barrel lug flange to contact the forend, if more epoxy is needed repeat the above procedure.
After it has been determined that you have a nice bedded area in the forend remove the tape from the barrel and install the forend, tighten the attaching screw and there should be a minor gap all the way around the barrel except where it is bedded against the lug flange, I like to have a gap about the size to slide a dollar bill between the barrel and forend.
The forend is now semi-floated which is the best you can do on the handi guns or any break open action type guns.
Next install the forend shoe onto the front of the action, slide the forend onto the lug and push into position, the forend should just barely touch the shoe, if it fits to tight remove the forend and sand the rear of the forend until it will easily fit into place.
Next remove the forend and the shoe, put a small amount of epoxy on the rear of the forend and press the shoe onto the forend and install the complete assembly onto the gun, tighten the attaching screw, wipe off any access epoxy from the shoe and forend and let the epoxy set up ( you should apply mold release to the bottom of the barrel above the shoe area to keep any epoxy from sticking to the barrel ). After the epoxy has set up remove the assembly and install the forend shoe attaching screws exactly in the center of the shoe holes. If you want to remove the shoe from the forend it will pop off very easily because the epoxy will not bond very well with the sick plastic.
You must understand the sole purpose of the forend is to give the shooter something to hang onto and with the shoe attached to the rear of the forend it will keep the barrel from falling off of the gun when it is broke open, the forend is not to be used to tighten the action by adding shims, if the gun will not lock up tight with out the forend them that is a whole other problem and should be corrected accordingly.
