Hunting Load Velocity Changes


Dear Technoid,

I am in the process of buying a new shotgun for goose hunting in the Norwegian mountains. In relation to this I have the following questions:

1) How does the mechanism (semi-auto vs. O/U or S&S) influence the pellet velocity?

2) Does shooting 2 3/4 inch shotshells in magnum chambers (3 inch) alter the performance of these shells as opposed to shooting them in 2 3/4 chambers?

Thank you for your answer!

Best regards

Terje Norway

Dear Terje,

This will have to be short as I leave for a week of duck and pheasant hunting in South Dakota, USA tomorrow morning. As usual I am spending my time doling out bad advice on Shotgun Report, rather than getting organized. No one ever accused me of having any discipline. One of these days I’ll have to develop a system- or just not unpack from the last trip. At least you are smart enough to think ahead.

As to your most excellent questions:

1) the velocity loss of a gas operated semi-auto vis a vis a fixed breed O/U, SxS or pump is almost zero. There is so little difference that it doesn’t bear consideration. Even magnum goose loads have achieved near maximum velocity before passing the gas ports. Additionally, the gas ports bleed off only a tiny percentage of the gas, so if the shell hasn’t quite reached maximum velocity when it passes the ports, it won’t make much difference at all.

The overall barrel length of any gun does have a slight effect on velocity. You may loose something approximately, more or less, vaguely 15 feet per second velocity for each inch the barrel is shortened. Note that I am fudging the exact amount because it depends on the shell as well as the barrel length. A typical goose load exits the muzzle at over 1200 feet per second, so losing 15 or 30 feet per second due to a shorter barrel doesn’t really matter enough to matter.

What does matter is picking the kind of gun that you feel comfortable shooting and that you shoot well. This is the primary concern. Being able to hit what you aim at is far, far more important than a few feet per second of velocity. For example, the only gun I am taking tomorrow to South Dakota is a 26-1/2″ Belgian Superlight O/U. While certainly not ideal for duck, I am not particularly worried that these short barrels will eviscerate my duck loads (Federal’s new Tungsten-polymer). I picked the gun because it is easy to carry for pheasants and also because I am too lazy to lug a pair of guns around the airlines. I also shoot it OK. Besides, no one ever expects writers to hit anything and I wouldn’t want to break that rule.

2) it is perfectly safe to shoot 2-3/4″ shells in a 3″ or 3-1/2″ chamber, though obviously not the other way around. I have experimented with 2-3/4″ shells in a 3″ chamber and found no difference in the patterns. Some people claim slightly better patterns due to a supposed “long forcing cone” effect of the 3″ chamber. I never noticed it. I have not tested 2-3/4″ in 3-1/2″ chambers.

It is important to remember that shotgun shooting, unlike rifle and pistol, is an “approximate” game. That’s why we shoot at birds with many pellets, rather than just one. A little pointing error is assumed. Neither of the two concerns which you have expressed will alter your lead or your pellet energy enough to make the slightest difference to that goose.

Best regards,

Bruce Buck
The Technoid writing for Shotgun Report, LLC

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