As apposed to hashing out the model 17's .22 L.R. cylinder in model 48 .22 mag puzzle,, found and bought second gun instead, a model 17-4 N.O.S. never shot gun in 8 3/8. So, two guns,each in their designed caliper is how I chose end up. I did find out though over on the Smith & Wesson site not only are they sending the .22 L.R. round down the .22 Mag's barrel,,,they are also doing the reverse shooting the .22 mag round down the model 17's .22 L.R. barrel and saying "that's the more accurate combo" Haven't found out if that creates adverse barrel wear, probably ruins it quick.