Does barrel length effect the tightness of the shot pattern?

[sbarkowski1]

I bought a H&R Tamer 20ga a few months ago for use as a compact and lightweight small game gun. The barrel on it is 20" with a fixed modified choke. I find the spread of the patten to be a little to wide and I was wondering if I got the H&R Topper 20ga with the 26" barrel and fixed mod choke if the longer barrel would be any help in producing a tighter pattern? Or will a modified choke produce the same pattern no matter what the length of the barrel?

 

[Sauer Grapes]

Modified choke is a modified choke. That choke selection is tight enough {or too tight} for most small game. IMO your barrel selection isn't practical for small game. Go get a barrel or another gun.
6 inches won't do anything for the pattern, but it will make a big difference in shootability of the gun.
good luck, I'm sure someone will chime in and say they always hunt with a 20" barrel.

 

[rbernie]

The length of the barrel has nothing to do with the pattern; the pattern is specifically determined by choke and the load used.

 

[Fred Fuller]

In a word, no. Patterning is influenced by the internal geometry of the barrel (forcing cone, bore size, choke etc) but not the overall length. The difference between 20" and 26" has an effect on the shooter more than on the shot charge, simply because the longer barrel is easier to keep swinging on a moving target than the shorter one.

fwiw,

lpl

 

[Bud Tugly]

Very short barrels give an advantage in hunting game like grouse, woodcock, or rabbits in thick cover. Ranges are always quite short and getting off one quick snap shot is typically all you get. A more open choke (wider pattern) is also a plus.

IMO guns like the Tamer are meant for these short-range situtations, and the choke may be more open on purpose.

 

[HGUNHNTR]

Agree agree agree, the shot has no idea what length of barrell it slid through.

 

[kirbythegunsmith]

Details

Speaking from a long experience working with shotgun barrels, certain circumstances prove that barrel length has an effect on pattern density and dispersal.
Turkey hunting and turkey match shooting where maximum density patterns are desired will, when all else is equivalent, tend to group more tightly with a longer barrel such as 30" vs. 20".
The 20" barrel is much more maneuverable for hunting and is a typically better choice for turkey hunting as an example.
I work at making those short barrels pattern very tightly for hunters so they can get performance more like a long barrel in a short barrel. That has more to do with the quality and precision of the work and if done to a longer barrel, would likely outperform the shorter barrel. See how many short barrels you see at the patterning contests; some have had to place barrel length limits on shooters to keep the longest barrels out and make the contest practical, the same way that many racing styles have engine size limits to keep the field more level. The proof that precision and talent mean a lot can be seen in the winning performance of certain racing teams, since all must play within the same limitations- but a few are always a bit faster with the same size components.

Shorter barrels may need a slightly tighter amount of choke to get equivalent results of a longer barrel due to the shot spread effect from the muzzle pressure that naturally drops as length increases. I believe it was the Churchill XXV that they said used a bit more choke to pattern the same as the 30" barreled versions.

It is true that most times the pattern, velocity, and hitting power will be little changed by modest barrel length differences, but can be radically different due to quality of bore contours, finish, choke alignment, and the details that make a fine barrel different from an economy barrel. However, shotguns being a fickle servant, we may sometimes find that what was considered likely a plow horse wins the triple crown in pattern density at long range. Thus is the nature of the beast- that no small sample comparison will ever show much to be able to conclude with certainty about most analyzed details. Some details will require much more exposure than anecdotal levels to reduce an uncertainty factor.

[email protected]

 

[blackops]

No, the choke determines shot pattern. Barrel length has more to do with application or your "swing." If you are looking for quick pull up shots, you would obiously want a short barrel.

 

[natman]

Speaking from a long experience working with shotgun barrels, certain circumstances prove that barrel length has an effect on pattern density and dispersal.
Turkey hunting and turkey match shooting where maximum density patterns are desired will, when all else is equivalent, tend to group more tightly with a longer barrel such as 30" vs. 20".
The 20" barrel is much more maneuverable for hunting and is a typically better choice for turkey hunting as an example.


Shorter barrels may need a slightly tighter amount of choke to get equivalent results of a longer barrel due to the shot spread effect from the muzzle pressure that naturally drops as length increases.

It is true that most times the pattern, velocity, and hitting power will be little changed by modest barrel length differences, but can be radically different due to quality of bore contours, finish, choke alignment, and the details that make a fine barrel different from an economy barrel. However, shotguns being a fickle servant, we may sometimes find that what was considered likely a plow horse wins the triple crown in pattern density at long range. Thus is the nature of the beast- that no small sample comparison will ever show much to be able to conclude with certainty about most analyzed details. Some details will require much more exposure than anecdotal levels to reduce an uncertainty factor.

[email protected]

I've always suspected that if there was any difference, it would be due to lower muzzle pressure to disturb the shot as it leaves the muzzle. It's the first rational explanation of a factor than might actually make a difference I've heard. I wonder how much a ported barrel/choke would decrease this effect?

Any quantifiable data to show how much of a difference we're talking about? A few extra pellets on the card might make a big difference to at a turkey shoot, but wouldn't really matter even to a turkey hunter, at least not enough to offset the very real difference in handiness in the woods.

 

[tactikel]

Agree with the above. If you need tigher patterns try different shot sizes and shell brands. Most buffered magnums (if you have 3" chambers) will pattern tighter than less expensive shells. Give hevi-shot a try it tends to pattern tighter.
I have a 870 special field 20 ga with a fixed IC choke, for 1st shot at Grouse I use standard field load, for second shot I shoot a Win XX supreme 3" mag it patterns about Modified thru my gun. Good Luck.

 

[MCgunner]

I shoot doves with a 20" 20 gauge coach gun, not a problem to 40 yards. I choke I/C-Mod and can cover everything from about 15 yards to 40.

 

[Owen Sparks]

I this myth contains a small grain of truth. Suppose some fudd decides to cut the barrel off of Grandads bird gun and make a "tactical" shotgun out of it. By removing a few inches of barrel he will remove whatever amount of choke it has and going from full choke to cylinder bore can make a dramatic difference. If he did not know any better it would seem like shortening the barrel was what increased the spread. There are enough fudds out there to perpetuate this myth.

 

[Red Cent]

Don't know the price of a new barrel.

You could have someone lengthen the forcing cone and backbore the barrel to 2-4" before the start of your MC from the muzzle. This mod will magnify the existing choke. Lengthening the forcing cone allows the transition of the wad into the bore of the barrel smoothly. Perceived recoil will be reduced. The back boring will open the bore from a nominal ID of .729 to, I would suggest, to, at least, .020 smaller than your modified choke. Most modified chokes create a constriction of approximately .023" making the last few inches of bore .706. I would use a .735" remaer. Then the wad containing containing the shot will be "swaged" at the end of the backbore and be further swaged when it encounters the MC. It is proven that backboring will improve pattern and create a uniform shotstring.
Simplify. Reamer inserted into chamber end a tapers and lengthens forcing cone. 30 minutes. Bacbore reamer inserted through the chamber and reams the barrel to desired depth. It is easy BUT, it is a little time consuming. If the 'smith has a lathe with mechanical ran flushing oil, he can do yhis part pretty quick. Then he polshes the bore and chamber. If he has used a good sharp reamer for both mods, very little polishing will be needed. The chamber is not touched.
Sounds complicated but is not. Kirby can probably expand on it. I would guess $100.00 to $150.00.