The author's Ruger Number One in .204 Ruger tends to group a bit better with the heavier 40-grain bullet than with the lighter, faster 32-grain slug. He thinks the heavier bullet carries much better as range increases.

The 6mms are also popular and extremely effective long-range varminters. The .243 Winchester is the most popular by a huge margin, offering (like the .22-250) a tremendous variety of loads, bullet weights and styles and a rich history of loading data, but there are faster 6mms, including the old 6mm Remington and the new .243 WSSM. The heavier 6mm bullet does better in the wind than any .20 or .22, so it is preferred by a lot of Western varminters who haul out their "big" 6mm (and in some cases .25) when the wind gets strong and the range gets long.

ROVING OR STATIONARY
Short-range varminting is generally a stalking game; because of the noise and your own presence, you generally have to move frequently to keep getting shots. But once you get out of rimfire range there's usually a choice between what I call roving-wandering a bit and taking shots as they come and setting up for deliberate, stationary shots. Some of us do a bit of both. Others like to use varminting purely as practice for big-game hunting, and also to get a bit of exercise.

Especially with prairie dogs and ground squirrels, you won't get as much shooting this way (or have as high a percentage of hits), but it's a lot of fun to move around and take shots from a variety of field positions. With rockchucks and woodchucks in small woodlot habitat, this is probably the most effective hunting tactic. Still others are more attracted by accuracy and precision. They unroll shooting mats and put up sandbags or set up portable bench rests, firing from one "stand" as long as targets are available, then packing up and changing location. I have seen wonderfully elaborate setups: bench rests mounted in truck beds, portable benches that include an umbrella for hot summer days, even custom-made flatbed trailers with bench rest, gun-cleaning table and reloading bench.

Almost regardless of the caliber you choose, the ideal roving varmint rifle is probably not the same as the stationary rifle.

The rimfires and even the .22 Hornet are roving varminters. There's no reason for them to be extremely heavy, and there's not much justification for putting a big scope on them, because the range is limited enough that you just don't need it.

The new .204 Ruger is shown with the light 32-grain bullet and the heavier 40-grain load. The former is faster, but at longer ranges the higher ballistic coefficient of the heavier bullet takes over quickly.

The faster centerfires diverge a bit. When you're roving it's unlikely that you'll stay in one place to overheat the barrel, so the ideal rifle might as well be pleasant to carry, more of a sporter weight than a true heavy varminter. Choice of scope depends a bit on you, but if I'm shooting unsupported, even from prone, there's a limit as to how far I can hit a prairie dog or ground squirrel, and high magnification won't buy me stability. An upper-end magnification of 10X or so is truly plenty, and that helps keep gun weight down.

Stationary varminting is where the classic heavy-barreled varminter comes into play. Such a rifle can be used from a variety of positions, but it's really meant to be firmly rested. It is, essentially, the sporting application of a benchrest rifle.

Weight is not an issue; the heavier it is, the more stable it will be and easy it will be to call your shots through the scope. The stock is blocky and heavy, adding to gun weight. The bottom of the fore-end is flat, designed to nestle snugly on sandbags or a rifle rest. The barrel varies from heavy to extremely heavy. This adds gun weight and, more important, allows you to keep firing longer before your shots begin to walk.