"Shotgun fit" is a term of vague familiarity to most duck hunters. They've heard it, but they've never really understood what a proper shotgun fit entails and how it can affect their shooting ability.

Instead, most hunters select a factory gun off the rack, and if it "feels right," they purchase it and start hunting with it - imprecise, but effective for the majority.

This is because most mass-produced shotguns come with factory stocks made for the shooter of average size, and the shooter adapts to the shotgun. Still, hunters should have an idea of what fit is all about and how to tell whether or not their gun might, indeed, need modifications to provide a better fit. Sometimes it's necessary to adapt the shotgun to the shooter instead of vice versa.

Here's the concept. A shotgun that fits is one that feels comfortable to its shooter, and when mounted, is a projection of the natural symmetry of his arms, head and eyes. In other words, when a shotgun fits, it rises fluidly to the shoulder and cheek with the shooter's eyes aligned naturally down the barrel without him having to think about it. This causes the shotgun to flow and point precisely where the shooter is looking. In contrast, a shotgun with improper fit feels clumsy in the mount and fails to achieve proper sight alignment naturally.

Steve Felgenhauer is a factory gunsmith for Browning Arms, and he offers practical advice about fit for hunters buying a factory shotgun. "First, when you mount a shotgun, check to see how much distance there is between your thumb and your nose as you're looking down the barrel. You need at least an inch of separation. With any less, there's a likelihood of recoil (especially when shooting heavy duck loads) causing your hand to strike your nose. This obviously breaks a shooter's concentration and negatively impacts his accuracy."

Felgenhauer says stock length is another important consideration. "A shotgun with a stock that's the right length in warm weather when you're wearing one thin layer of clothes may be too long when it's cold and you're wearing several layers of heavy clothing. This can be remedied by adding a recoil boot in warm months to increase stock length and then taking it off during cold months."

Felgenhauer says another way to adjust stock length is to add or remove spacers that come with most guns in front of the recoil pad. He also notes that in extreme cases, a wooden stock may be shortened by cutting it to a desired length.

When it comes to getting a proper sight picture, Felgenhauer says this is a matter of personal preference. "Some hunters like to see part of the rib and the bead. Others want to see the bead only. This is a matter of whatever works best for the individual."

Felgenhauer says the best way to discern what works best is to take a shotgun to a trap range and shoot straightaway targets repeatedly. "Just see what feels right and what sight picture is working best.

Then make whatever stock adjustments you need to to get that sight picture without having to think about it."

Overall, Felgenhauer says most hunters can get a reasonable fit by making their own adjustments to their shotguns. However, a discriminating shooter may consider working with a qualified gun fitter to alter the stock on a shotgun or to replace the factory stock with a customized, made-to-fit stock. Obviously this option requires more expense on the shooter's part to achieve the high quality he demands.