If you will measure the barrel diameter of your 61, I will measure a Model 42 barrel for you. The standard Simmons solid rib looks great on a Model 42. The other vendor who does Winchester matting is the Gun Works of Central New York, a pretty good shop, I have heard. Both have websites. Simmons actually installed their 1/4" ventilated rib on some few smoothbore Model 61s. They are actually in early Simmons catalogs.