How does barrel lenghth influence performance?

[Para Bellum]

I recently spoke with a hunting instructor about how shotgun-cartridges are built and we began asking ourselves, how barrel length would increase performance.

I e.g. have a 12ga with 18" barrels (nice coach gun).
Would the slugs/shot from this gun actually be slower than from a "long" shotgun?

PB

 

[Lee Lapin]

Probably not. Most modern smokeless powders do their work in 14- 18" of barrel or so. Slower burning powders may want more, faster powders could get by with less. As with so many shotgun questions, the only really good answer is, "It depends... ."

lpl

 

[Dfariswheel]

The NRA did a test some years ago.

They bought a Marlin Goose gun with 36" barrels and ran tests by chopping 1 inch at a time off, installing a choke and firing the gun for velocity and pattern.

Their results were:
Anything that was going to happen in a shotgun barrel happens within 18 inches.

Anything over 28 inches and you start to loose velocity due to friction.

Barrrel length has little to do with pattern.

The test gun was cut to 12 inches before "Things started getting out of hand".

The idea a longer barrel shoots "farther" or "harder" is a left over from the black powder days.

 

[oneounceload]

The longer barrel is good for swinging with the target - nothing more

 

[Jim Watson]

The famous (if you follow English shotguns) Churchill XXV was based on trials with the shells of the day which showed that a 25 inch barrel was necessary and sufficient for full velocity and good patterns.

I don't think you will get the most speed out of an 18" 12 bore, but it will get most jobs done.

 

[hogdogs]

If the shot load is not 100% at 18 inch it is gonna be in the high 90's so I doubt 18 inches is gonna limit my gun's ability...
Brent

 

[RetiredLawman]

 

[SumToy Custom Barrel]

We do alot with the target guns. We try to get the most shot in the smallest spot. I have got a 22 inch Winchester that will stand it's own with the 36 inch barrels. If you get the chamber a chock to work together barrel length don't have anything to do with it. The longer barrel just gives you a better sight plain. The down fall to the long barrel is that you will see the unsteady hand show up more on the paper.

 

[bcarver]

Barrel length

There are several parts of a barrel
1. chamber 2.75 3 or 3.5" usually.
2. Forcing cone. This is the section from the chamber to the bore.
A short cone deforms shot and cause recoil. A longer cone eases the transition, reduces recoil and preserves the pattern possibilities.
3. Bore 12 to 14" is all that is needed with current loads.
Gun manufactures made shorter barrels so ammo companies made shells to shoot in them. Or vise versa. Its a chicken or the egg thing.
Bores can be polished smoothed,"lined" or rifled.
Lined and rifled bores with thin lines cut either straight or spiral respectively.
Wider bores make better patterns. "overbored" "backbored" are two types.
Different manufactures use different bore widths ans some manufactures differ from model to model.
4. Choke is the constriction at the end of the barrel.
It tightens the shot column. It is the final adjustment to the pattern.

All of these are much more important than length,

 

[Brad Clodfelter]

You guys pretty well have said the specifics and I would agree. I will admit that the shotgun pattern testing I have done vs shooting 21" barrel vs 26" or 28" is that the 28" barrel will put about 10-15 more shot inside a standard piece of copy paper at 25yds vs the 21" barrel. That's trying various choke tube constrictions and various brands of turkey loads. Now that ain't much difference, but having said that I prefer the 28" barrel.

 

[freakintoguns]

hmmmm, so by the chart Retiredlawman put up, my 18" remington 870 should be just fine for hunting deer.... or would i want that extra couple hundred FPS by goin to 26" barrel?

 

[Dfariswheel]

That depends on several factors:

1. How YOUR specific gun and barrel works with a specific brand and type of shells.

2. How far away the deer are.

3. How BIG the deer you'll be hunting are.

Number 1 is probably the most important.
Shotguns, barrels, and shells can vary wildly in performance.
What shoots just great in one gun/barrel/shell combo will shoot terrible in another.

 

[TheManHimself]

Realistically, no deer is going to be able to tell the difference between a 1600 FPS projectile and a 1500 FPS projectile, especially when the projectile in question is a one ounce chunk of lead.

 

[Para Bellum]

One more reason to like my coach gun!

Folks,

thanks a lot!
Your knowledge gave me one more reason to like my coach gun!

http://www.baikalinc.ru/en/company/54.html