In a previous story I spoke about the importance of consistent accuracy for a hunting rifle. That is, the rifle’s ability to hit the point of aim, day after day, week after week. When our rifle lives up to our expectations it is a wonderful thing, but when it does not it can be frustrating and confusing. Essentially, when we fail to hit the aiming point there are three possible causes: ammunition, the mechanics of the rifle, or the person behind it. The first two are relatively easy, so we will begin our witch hunt there.
Ammunition and load development receive a tremendous amount of attention. Part of this is necessity, but mostly it is the luxurious fun of finding the “perfect load.” I can tell you that tinkering with the minutiae of reloading—powder charges, primers, case uniformity, etc.—have little bearing on realistic hunting accuracy. Bullets are somewhat different. First, hunting bullets should be chosen carefully for their ability to perform on game. It is better to use a “two-inch” bullet that penetrates and kills well than a half-inch bullet that is unreliable. However, the finest game bullets on Earth are also exquisitely accurate, so a hunter does not need to give up fine accuracy for extraordinary bullet performance. But the brand, style and weight of the bullet can, at times, have a huge effect on accuracy. I have barrels that simply hate the solid copper bullets, others that love them. At times a boat-tail will truly offend a sporting rifle’s barrel. The bottom line is if a given bullet does not shoot reasonably well, try another. The really good news is most modern rifle barrels (and old ones also) are more than accurate enough to meet our needs and one bullet or another will answer well.
When a rifle fails to consistently put a pair of shots in two or three inches at 100 yards and then repeat that over a period of time, we need to look at its “moving parts” to see if anything is wrong. Sometimes the fix is surprisingly easy and basic, if we know where to look.
BEFORE YOU BEGIN TO INVESTIGATE THE RIFLE BE ABSOLUTELY CERTAIN IT IS UNLOADED!
The first place to look is as basic as tying your shoes. Before I fire any rifle I check its “guard screws.” Presuming it is a bolt action these are the two large screws that clamp the barreled action and stock together. Finding them loose is not uncommon. If we use the more common styles of bolt actions as a model, there is one screw in front of the trigger guard and one behind. The front one should be very tight, almost as tight as you can comfortably make it with one hand on a screw driver. The rear screw should be “moderately” tight, just good and snug. Having these properly adjusted will do two things. First, it keeps the metal from banging around in the stock where it is likely to damage the wood or even synthetic stock itself. Second, it helps ensure consistent accuracy. Or said another way, if the guard screws are loose, the rifle is almost certainly not going to shoot well.
Next in the line of suspects are the sights, or more accurately the scope and its mounting system. Unfortunately, detecting “looseness” in the scope system is much less easy than the guard screws. However, if the rifle is misbehaving, scope mounts and rings are often the guilty party. Begin with what seems a ridiculously basic test. Hold the rifle in one hand and see if you can detect any wiggle, or movement, in the scope. If you feel the slightest wiggle, you have found the culprit. Quite often recoil will loosen the four screws that hold the scope-mounting bases to the receiver. If you are confident and have screw drivers that fit correctly, you can fix this yourself. Hold the rifle in a padded vise and remove the scope by taking the rings out of the mount. Then, with the base-mounting screws exposed, check to see if they are tight. These screws should be really tight, reefed-on to maximum. I like to take them out and put a drop of blue (removable) Loctite on each screw before I tighten them. If you are not experienced and comfortable with the process, it is probably best to defer to a friend or gunsmith who is.
Many kinds of scope mounts have a rotary dovetail that attaches the front scope ring to the bases and two large opposing screws on either side to hold the rear ring in place. This is a relatively weak system that often has problems. Look closely at your front ring and see if you can detect any evidence that the scope has slipped in the ring. This will usually look like a dark or light mark on the scope itself, right behind the front ring. If so, you will need to loosen all of the screws that clamp the rings to the scope and loosen the two big screws in back as well. Position the rear ring properly in these two big screws and tighten them. Follow this by gently tightening all of the ring screws. With all of these things in place, your scope should be solid and mounted reliably.
If the problem persists it is more than reasonable to make the scope itself a suspect. Yes, even the most famous are liable to internal failure. The best test for scope problems is to put another scope on the rifle. If it becomes accurate, return your scope for warranty repair. If you still do not have accuracy, we need to look further.
Along with everything else it is always a good idea to scrub your barrel; sometimes, albeit rarely, enough fouling and badness can accumulate in the bore to make the rifle unhappy.
Another very critical part of the rifle is the muzzle crown. This is the very end of the rifling, the last thing that touches the bullet before it leaves the rifle. It only takes a minute flaw in the crown to throw bullets around wildly. I use magnification to look at the crown. Look for any dents, dings or burrs. Also, after you have fired the rifle and before you have cleaned it, look at the “crown-pattern” left by the powder residue. This is a geometric pattern of “smoke” that will appear at the muzzle. Each land and groove should have an identical print. If you see something out of order, there is probably a problem with the crown. In any case, if you detect or suspect trouble, it is time for a skilled gunsmith.
Finally, we must consider a part that is linked to the last possible cause of inaccuracy. The quality of the trigger pull can have much to do with your ability to make the rifle perform well. Rifle trigger pulls vary from wonderful to almost impossible. Good trigger-pull gauges are available and are not expensive. These allow you to check the pull weight on your rifle. If you find that it is more than five or six pounds, I suggest you have a qualified person make it more user-friendly.
With the common and obvious mechanical problems behind us, if the rifle still does not perform well, we are faced with two ugly possibilities. First, the rifle, and most likely its barrel, are truly bad. This is rare, but it happens. Like the scope test, we need to be sure and the easiest way is to try another shooter. Ask another person to give the rifle a try. If it is accurate for him we have discovered a dark truth; we need to examine the person behind the gun. But not to worry, we can fix them, too. Stay tuned, as we will look for ways to help you get the most out of your rifle, both on the benchrest and in the field.
