Wsjones,
I took some careful measurements of my forend and found that the front steel strap had about .025 looseness around the magazine tube but the rear strap had about .055 inch slop. The rear steel strap had been inletted into the wood a little higher than the front one. I don't know if that was done on purpose but that explained the looseness I felt in the forend.
So what I did was cut a section out of a copper pipe, formed it to the same radius as the magazine tube, and epoxied it to the underside of the rear strap. That made the looseness front and rear about equal. That made a huge difference in how the forend feels. It's much more solid and yet still cycles easily.
The pics show the piece of copper in place and with the magazine tube also. Notice the copper doesn't go around the sides of the magazine tube, it's just on top where the excess space was.
I suppose I could've used a piece of nylon or even teflon but the pipe was handy and had the right wall thickness, etc. Also, I doubt if epoxy would've stuck to nylon or teflon.
Tom P.