Here is a look at what I did to my Nova, even if you didnt have a mag extension im sure it would work on the barrel. I just got the parts from amazon and they're surprisingly solid, and seem like reasonably good quality.
http://www.amazon.com/gp/product/B00...ls_o00_s00_i00
http://www.amazon.com/gp/product/B00...ls_o00_s01_i00
I just got some really thin weather stripping cord and lined the clamp so it wouldn't scratch up the mag extension.