By Glen Wunderlich Outdoor Columnist Member Professional Outdoor Media Association
After experimenting with my Marlin semi-automatic .22 Winchester Magnum Rimfire (WMR) rifle and myriad ammunition variations, it was time to give it up. It never performed to expectations, failing miserably at the target bench and afield – even after having the factory install a new barrel. At Meal and More in Morrice, I traded it for a Savage model 93R17 in .17 HMR (Hornady Magnum Rimfire).
The diminutive .17 caliber cartridge is actually a .22 WMR case necked down to accommodate 17 and 20-grain bullets, which are propelled at advertised velocities of 2550 fps and 2375 fps respectively, making it the undisputed leader in rimfire velocity.
The .17 HMR evolved from a joint project between Hornady, Marlin, and Ruger, was introduced in 2002, and has become a huge success. From everything I have read, the .17 HMR enjoys a distinct advantage over the .22 magnum in the accuracy department regardless of bullet weight, configuration, or rifle manufacturer. It was time to find out for myself.
I opted for the heavier 20-grain ammo, choosing Hornady’s XTP offering, which is a controlled-expansion design. Other choices include full-metal jacket and explosive varmint bullets.
The Savage rifle came with an inexpensive Simmons 3 x 9 power scope and I figured I’d at least try it. I set targets at 50 yards and began punching paper. To my ultimate surprise, the little bolt gun never shot more than ½-inch groups with some in tiny clover-leaf clusters!
I realized I was on to something well beyond expectations, but as usual, my desire for improvement led me to check for parallax in the optics. On any scope without an adjustable objective lens (AO), parallax will be present to some degree at any range for which the scope is not set. Most rifle scopes are set to be parallax free at 100 yards, although some manufacturers such as Leupold are set beyond that. Rimfire scopes are typically set at 50 to 75 yards.
What does this mean? Parallax is defined as the apparent change in the position of an object (target) resulting in the change in the position from which it is viewed. Parallax is most noticeable at close range and can be checked easily. Just place your scoped firearm on a solid rest focused on a target. Then, move your head up and down, or side to side without touching the scope. If the target appears to move, you have parallax.
Parallax is problematic. If your eye is not positioned in exactly the same location before each shot, group size will suffer. Whether you are aware of it or not, parallax can account for poor shooting all by itself. With fixed parallax scopes, it’s like pedaling a bicycle with only one gear. Sometimes it will be just right; the rest of the time it won’t.
The obvious answer is to change to an adjustable objective scope, which permits focusing at any given range. Although the Savage has a fine adjustable Accu-Trigger, it’s not as costly as the Ruger model, and therefore, spending big bucks on a scope seemed inappropriate. I found a BSA Sweet 17 scope with AO in 3 x 12 power for a scant $65 on sale at MidwayUSA.com right now and couldn’t resist. The BSA scope seems like a fantastic deal with its screw-on scope caps, adjustable parallax, power range, and best of all, range compensation out to a whopping 300 yards!
The scope is made to work with 17 grain bullets traveling at 2550 fps, but I found that the little Savage was spitting out the 20-grain XTPs at that velocity and the 17 grainers a bit faster. It will be interesting to find out how the scope performs, once installed – especially at the longer ranges.
