Fellow writer Dick Williams has been known to contribute to the delinquency of handgun fans, particularly those who are susceptible to his influence. I was once on a varmint hunting trip with him and he showed me the neatest revolver. A Model 648 Smith & Wesson made some years before, it's a stainless steel .22 Magnum Rimfire revolver. It had a six-inch underlugged barrel but it was chambered for that pricey .22 Magnum ammo. He had the mechanical wizards at S&W fit a stainless steel long rifle cylinder to the Magnum revolver. Now he had the best of both worlds. I appreciated the utility of such an arrangement..

When I checked on availability of the M648, I found that Smith and Wesson had discontinued it. I contacted Tony Miele, boss of the Performance Center. I asked him about the feasibility of converting the M617 from .22 Long Rifle to .22 Magnum by adding a cylinder. It'd take a little more than that he opined, but it was certainly possible. There was the matter of the forcing cone and its dimensions. He agreed that it would be a fine Performance Center project. Checking further, I found that this concept was agreeable to all concerned.

http://www.theoutdoorwire.com/image_archive/2205510.jpeg> The S&W Model 617 – originally .22 LR only – was remarked by the Performance Center. The Magnum cylinder shows evidence of test firing by author. http://www.theoutdoorwire.com/image_archive/2205512.jpeg> Beauty shot http://www.theoutdoorwire.com/image_archive/2205514.jpeg> That's a lot of gun steel for .22 rimfire ammo, but it's very steady on target. http://www.theoutdoorwire.com/image_archive/2205516.jpeg> Remington Premier Magnum Rimfire had a ¾" group without the flyer in this effort, which totaled 2 ¼" for all rounds fired. http://www.theoutdoorwire.com/image_archive/2205518.jpeg> Winchester 36 grain Plated HP gave this group on the Birchwood Casey "prairie chuck" Shoot-N-C target at 25 yards.

http://www.gunpartscorp.com/>Gun Parts Corporation had a six-shot Model 648 cylinder, which I ordered. I packaged it up and sent it in to be combined with a six-shot, six-inch Model 617 .22 LR.

When it returned, I saw a very stock looking revolver come in the standard blue box. The only obvious change was the spare cylinder. Glancing at the left side of the barrel, I saw the inscription, "22 M.R.F. CTG." That's new, as the gun came off the line as a .22 Long Rifle. Opening the cylinder, I saw it was marked "L.R." The spare cylinder is marked "MAG" on the rear face.

The gun weighs in at 45 ounces, making this a very hefty K-frame and it's just short of a foot long. The weight is tipped out front. With the full-length underlug and the tiny hole cut through that slab of steel, it's no wonder that the revolver is heavy and that the weight is forward. The sights are black. The rear is the S&W adjustable "micrometer" sight. The front is a patridge, pinned in place to allow changes.

The trigger and hammer are wider than "service" grade and narrower than "target" triggers and hammers. The face of the trigger is smooth.

The stocks (actually a "stock" in this case) is the rubber Monogrip by Hogue. A curvy, ergonomically correct "grip," the Hogue was first conceived and patented by Guy Hogue. Guy, an LAPD firearms instructor and armorer, knew how the human hand operated and built his stock to fit.

My original exposure to the Model 648 Convertible was during a hunt. We were at the Spur Ranch in Wyoming and our prey was varmints. We had rifles but some of the best shooting was on close-to-midrange prairie rats and ground squirrels. I used Dick's revolver with some LR ammunition but quickly saw the difference when shooting from the magnum cylinder.

The .22 Magnum Rimfire has a sharper report. The effect on our small pasture-killers was sudden and more extreme than when using Long Rifle ammo.

At my home base, I'm only able to "hunt paper." I set up some targets and began working on them. The groups were shot at twenty-five yards from a bench over the Gorilla Range Bag by Shooters Ridge.

The first thing I noticed was that each group came with four rounds in tight and one "outrider." It's likely that I was pulling a round out though after firing several groups, I was getting a feel for my trigger press and called shots. One notable group had three in a cluster with two out. The remainder was "four and one."

When shooting .22 Magnums, I found that group averages were running just under two-inches with most loads. The sole exception was a nearly-three-inch group rendered by CCI Maxi-Mag 40 grain solids. I took note that .22 Mags weighing somewhat less than the 40 grain standard seemed to show the most accuracy in the converted M617. The 40 grain load was the least accurate in this gun.

In the Long Rifle cylinder, Federal Classic solids gave a 2 5/8" result while Winchester Super-X put five bullets into 1 ¾" and CCI 32 grain Stingers put five holes into 1 ½".

I noticed that the single action trigger was fine; it's short, with no slack and it breaks cleanly.

I put up a Birchwood Casey "Shoot-N-C" target in the form of a "prairie chuck" silhouette. I had Winchester "555 Rounds" 36 grain Plated HP ammo. From twenty-five yards, I put four bullets into the 3" scoring rings and one, at about 2:00 o'clock touching the outside scoring ring. The group measured 2 ¼".

This heater is just the thing for small game and varmint control

http://www.smith-wesson.com>Smith & Wesson

- Rich Grassi

Grassi is founder and editor of our companion service, The Tactical Wire(www.thetacticalwire.com).