I am a new clay shooter. I have read most of your technoid articles but could not find the answer to what I think is a basic question. In your articles you state there is a direct correlation between choke size and shot size to determine optimal patterning for specific distances.
Question: How does barrel length figure into all this? What is best the best length for each type of shooting, bird, skeet, and trap?
Thanks in advance,
You’ve read “most” of my Technoid articles?! Attaboy! I’m not sure that I could wade through most of them. In a fairer world, you would get a medal.
Yours is one of those simple sounding questions that isn’t. Like “What’s the meaning of life?”, it leads to a long answer. Therefore I will a lot this question the maximum amount of time: one cup of coffee. You have your way of keeping time. I have mine.
Barrel length has nothing to do with patterns. You can get exactly the same patterns out of a 20″ barrel as you can out of a 30″ barrel. There will be a slight difference in velocity, but not a meaningful one.
The reason to select one barrel length over another is:
1) overall balance of the gun, and
2) sighting plane.
Shotgun balance is like chili. Everyone has their own opinion. All else being equal (and it seldom is), the longer the barrel the more the shotgun balances toward the front. There are ways around that, but as a general rule, it’s a general rule. Shotguns built for quick manipulation, such as upland bird guns, tend to be neutrally balanced with the weight between the hands. Guns meant for the kinds of shooting where a steadier swing is more of an asset than speed (trap and skeet) tend to be balanced with a good bit of the weight forward. Skeet O/Us with their added tube sets can be extremely nose heavy, though that weight is more due to what’s in the barrel rather than barrel length alone.
Now for the heavy lifting: barrel length, as it contributes to barrel weight, affects not only the point of balance, but also the moment of inertia of the gun. Both contribute to the “feel” of the gun. The point of balance (POB) of the gun is the fulcrum where it balances on your finger when you knowingly test it in the store in front of your awed friends. It’s of some importance, but not great importance. Moment of inertia (MOI) is far more important. That is a gun’s resistance to changing direction. I feel that MOI has more to do with a gun’s “feel” than POB.
I’ve used this example before, but it’s really clever so I like to trot it out at every opportunity so that everyone gives me credit for it. Take a broomstick and put a brick on each end. The broomstick “gun” balances in the middle (POB), but when you swing it the gun is hard to start and stop (MOI) because it has the weight at the ends like a skeet and trap gun. Now take the same bricks and put them side by side in the middle of the broomstick. The POB has not changed. Still balances in the middle. But the MOI has definitely changed. The “gun” is now quick to stop and start like a field gun when you wave it about . Grind the bricks up and magic glue them evenly all along the stick and POB is still in the middle, but the MOI has changed yet again to a more neutral feel. Most people would feel that the broomstick with the ground up bricks evenly distributed was the best balanced.
Barrel length can affect balance and feel more subtly too. A short, heavy barrel of 1.5 kg does NOT feel the same as a longer barrel of the same weight. Also, adding weight to the barrel in one place (such as the clamp-on weights skeet shooters use in the 12 to compensate for a tube set) does NOT give the same feel as stretching that added weight out over the length of the barrel (as it is when skeet tubes are in place). Same barrel length, same weight, same balance point, different MOI.
Sighting plane is a can of worms (as opposed chili). If you shoot a pre-mounted gun (trap and American-style skeet) AND if you position your eye so that it looks right down the rib, there is no sighting plane in the sense of the word. When you look flat down a rib you can’t tell if that barrel is one foot or one hundred feet long. Sighting plane only becomes apparent when your eye is above the rib, not on it. It’s like looking down a highway with your face pressed into the macadam (dead skunk style) vs looking down the highway while standing up. You need parallax to judge distance and length.
So, in the low gun games of hunting, sporting clays and international skeet, barrel length does matter as far as sighting goes because you do a great deal of your “aiming” and lead adjustment while the gun is off the face and the barrel is angled enough for you to appreciate its length. In the typical sporting clays or passing duck shot, the muzzle is put on the bird while the butt is still under the arm. The bird and muzzle speeds are blended, the gun is raised as the lead is achieved and the shot taken when it touches the face. “Move, mount, miss”- you know the drill. The muzzle is an integral part of obtaining the lead and you can see the muzzle because it is at an angle. The longer the barrel, the further the muzzle is from your eye and the less perceived lead there is (I did cover this once before because I got a lot of flack about that last statement, but I’m sticking to my guns). So, long barrels do affect lead when shooting low gun.
When shooting premounted games like trap and American-style skeet, long barrels don’t really affect lead as much because the shooter is always looking flat down the rib, or nearly so. Many shooters, particularly some trap shooters, like to see a bit of rib to stack the beads (I certainly do) but it isn’t all that much and three or four inches of extra barrel length won’t make that much difference. In trap the barrel length is there mostly for the balance and stability having more weight further out front gives you. It’s like hanging a bloop tube on your silhouette rifle. The more weight you can get up front, the more stable you are up to the point where you can’t move the gun properly. Trap isn’t a game of big movements anyway. Skeet is a game of big horizontal movements, but with careful selection of pickup points and knowledge of the fixed flight path, heavy guns do offer the advantage of enforced follow through (called inertia).
And now (finally) to your question: best barrel length for birds, skeet and trap? The general rule is that the faster you have to move your gun, the shorter the barrel. Typically ATA single barrel trap guns for 16 and handicap will be in the 30″ to 34″ length. An ATA doubles gun or an Olympic bunker gun will often be an O/U of 30″. Skeet O/Us these days are mostly 28″. Game guns are all over the ballpark because game varies so much. Grouse hunters often favor fast, short guns of 26″ to 28″, while goose hunters will want longer barrels of 28″ to 30″ to hold those Roman candles. 28″ is a popular length for pheasant hunting, though certainly not universal. These lengths are all for fixed breech guns like O/Us and SxSs. Pumps and autos are about 3.5″ longer due to their extra receive length so you might go a bit shorter there.
Coffee’s done. I’m done. Going shooting.
The Technoid writing for Shotgun Report, LLC
(Often in error. Never in doubt.)