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The Importance of Patterning Your .410 For Point of Impact

By Steve Thornhill.

Introduction

Last year I purchased a 36 gauge side by side muzzle loader. The gun is close enough in size and shot load (5/8 ounce) to a .410 to have many of the same performance characteristics that make the .410 so endearing. You can look at my other posting on this website titled .410 and 36 gauge to view the gun and the actual barrel size difference. It was because of an early experience with the little muzzle loader that I’ve decided to write this article.

 It was near the end of hunting season and I’d just purchased the 36 gauge side by side muzzle loader to use in my on going pursuit of pen-raised pheasants. I hurriedly inspected the gun, gave it some needed service and rushed it to the field. When I was inspecting the gun I realized that the guns comb only had about 2 inches of drop at the heal. Past experience told me that with such a high comb on the gun I would tend to shoot a little high. I wasn’t worried; in fact I figured that it would be just the thing for the close flushing fast rising birds I knew I would find.

The first pheasant flushed and I was rewarded with an easy shot with the little muzzle loader. My dog Samba retrieved the downed bird and we were off looking for another. It took me eight shots before I finally bagged my second bird! What happened? A trip to the patterning board revealed my problem. For some reason the gun was shooting low, instead of shooting over I was shooting underneath the birds!

 The point to the above story is that it’s important to pattern your gun, especially a gun as unforgiving as the .410 can be. Otherwise you could end up like me, missing shot after shot and not knowing why. Patterning is really quite simple and straight forward. If you’re shooting your .410 properly you’re not aiming it per se, rather you’re pointing it. To learn where your gun is shooting, put up a large sheet of cardboard (a nice sized piece from an appliance box is good) draw five small black circles on the cardboard, one near each corner and one in the center and then step back 50 feet. Starting in low gun position, smoothly bring your gun up to your shoulder and quickly shoot at one of the circles, just as you’d shoot at a bird or a clay target starting from the low gun position. Repeat four more times shooting a fresh circle each time. Do you note a consistency as to where the shot is hitting the paper in relationship to the circle? That is your guns point of impact.

 Typically, it’s the placement of your cheek on the stock that predicts where your shot will hit. The standard stock on a modern American made shotgun has about 2-3/8”s of drop at the heal (DAH). Older shotguns as well as shotguns from other countries often come standard with more or less DAH. 2-3/8”s DAH is the amount of drop that the American gun industry has decided works well for the average shooter. If you are that fortunate shooter who can do well with the standard stock, raising the height of the comb will tend to make you shoot above the target, while lowering the height of the comb will tend to make you shoot below the target.

The point is you won’t really know where your gun is shooting until you pattern it. After you learn where your gun is shooting you can either adjust your stock or adjust your shooting view to compensate for where the shot is actually hitting. For instance, the next time I took the 36 gauge out I made it a point to cover the bird with the end of the barrels as I pulled the trigger. With this one shooting adjustment, three out of the next four birds fell to the little muzzle loader, much better!

 In addition to patterning for point of impact that I’ve described above, there’s also specialized patterning for regulation. Double guns are regulated at the factory so that both barrels shoot to the same point of impact. Several things can throw the regulation off including the rechoking of fixed chokes by machining, resetting the ribs between the guns barrels, field accidents including mild ring bulging at the end of the barrels, and occasionally you’ll get a poorly regulated set of barrels from the factory. The answer is to pattern both barrels separately on two target sheets and look for consistency between the patterns shot by each barrel. If both barrels are not shooting to the same point of impact, I recommend that you pursue the matter further with a gunsmith who specializes in double barreled guns and/or read up on the subject.

Steve.