By Phil Bourjaily

The standard advice for choosing a new shotgun is to "pick the one that fits you best." To determine fit, many shotgunners simply throw the gun to their shoulder and squint down the barrel. If your dominant eye aligns with the rib, the shotgun "fits" and you buy it.

This is a good start, but minor adjustments might be needed if you want the gun to truly shoot where you point it. Fortunately, manufacturers are now offering firearms with kits that allow you to tailor the stock for a better gun fit.

Following are several tips on how to fine-tune your gun to increase your shooting success.

Perfecting Gun Mount

There's no use in fiddling with stock dimensions until you can develop a consistent gun mount. If you don't bring the stock to the same spot on your face every time, you won't consistently shoot where you look, even if the gun fits you to a tee. Gun mounting can be practiced at home, but always make sure the gun is unloaded before you start. Focus on smoothly raising the gun to your face and then tucking the butt into your shoulder. With the gun properly mounted, you should be looking straight down the rib. Practice gun mounting until it becomes almost second nature.

Checking Point of Impact

To check your point of impact, shoot the gun at a target 16 yards away. A hanging bedsheet with a small mark in the center works very well, because it won't allow you to see the exact point of impact and make unconscious adjustments. Screw in a tight choke. Then mount the gun and shoot it as if at a bird. Shoot the target five times without aiming the gun. You should focus on a consistent gun mount rather than on pinpointing the target. After a few shots, a hole will appear in the sheet at the densest part of the pattern.

Adjusting Fit

Look at the hole's position relative to the bull's-eye. If it's dead center or slightly high, your work is done. If it's more than an inch or two high, choose a shim that increases the drop of your stock. Every 1/8-inch adjustment should move the point of impact two inches at 16 yards. If your gun is shooting low, raise the comb. If it shoots to the left or right, adjust the cast. Then repeat the sheet test to see if you've got the gun shooting where you want it to.

Correcting for Comfort

You can adjust your gun further to make it more comfortable to shoot. Check the length of pull, which is measured from the front of the trigger to the end of the pad or buttplate, by seeing if you can fit two finger widths between your nose and the thumb knuckle on your trigger hand when the gun is fully mounted. If you can't, you risk a recoil punch in the nose and want more length. You can lengthen the stock with a slip-on pad or spacers.

Some guns have more castthe lateral bend of the stockat the toe (bottom) of the stock than at the heel (top), which helps to keep the toe from digging into a shooter's chest. You can experiment by removing the bottom screw of your recoil pad and twisting the pad outward. Making such a change permanent will require an aftermarket pad plate like the Jones Stock Adjuster.

Pitch is the angle of the butt relative to the barrel, and it determines how the gun fits into your shoulder pocket. If a gun kicks you in the face, it may have too much upward pitch. Back out the pad screws and put two or three quarters at the top of the pad to act as spacers. If the gun has too much downward pitch and tends to slip off your face, try adding some quarters as spacers at the bottom. When you find a comfortable angle, take the gun to a gunsmith who can either cut the stock down to size or add an angled spacer between the stock and pad.