Is there a barrel length that reduces velocity?

Status
Not open for further replies.
N

NoAlibi

Member
Joined
Jun 22, 2009
Messages
500
Location
Boca Raton, Florida
Is there an increased barrel length that reduces velocity?

I have some experience with target .22 rifles using target ammo and there is an increased barrel length at which velocity starts to decrease.

Do shotguns because of their rather short range of velocities have a similar point of increased barrel length that velocity loss occurs?

Is there a rule of thumb about this for the varying loads that are put through shotguns?

I'm going to use this info as a starting point for some of the decisions about my shotgun inventory. Thanks -- NoAlibi
 
Last edited:
Whoda thunk it

While the loads listed are considerably heavier than I shoot, there seems to be a pattern (no pun intended) that 28" is optimal.

Gee, don’t you think it was a lucky guess by shotgun manufacturers that the standard length barrel for a 12 gauge hunting shotgun is 28"??? :eek:

I'm sure many folks figured this out intuitively, but it’s nice to see it supported by data.

Any other links to payloads in the ounce to ounce and a quarter range just to see if the phenomenon translates?

rc - thanks for the link – NoAlibi
 
Last edited:
Barrel length varies from time to time. Churchill determined that 25" was the best length for British style driven shoots. Many upland guns for eons have been made in 26" lengths, while goose guns had 34" lengths
 
I chrono'd a couple of .22lr rifles that I used to own several years ago. My blued Marlin Model 60 22" had a lower muzzle velocity than my Ruger 10/22 18" carbon fiber barrel. I believe it was around 80-100fps difference with the Aguila Supermax hyperspeed loads, and less with the normal speed ammo. I miss the Marlin a little, don't miss that particular Ruger at all.

The Ruger with that barrel couldn't hit the broadside of a barn, while the Marlin would drive nails at 100yds.
 
Thing is most, no make that almost all, shotguns of 12 bore are issued in 30" barrels with 32", 28" and sometimes 26" as options as was the 10 and 16 bores...the lovely 20 bore was issued mostly with 28" barrels as was the 28 bore and the .410 gauge came with either 28" or 30" barrels depending if it was a pump (28") or double (30")...You'll find lots of 29", 27" and 25" in older English guns...and lots of Euro guns with 80, 78, 76 and 74 cm barrels...

BARREL LENGTHS
INCH......CM
32..........81.2
31..........78.7
30..........76.2
29..........73.6
28.....…...71.1
27..........68.5
26..........66.0
25..........63.5
24..........60.9
20..........50.8
18.5.......46.9

Convert inches to mm x by 25.4---mm to inch x by .0394---

The lengths were there from the old blackpowder days where the extra length was needed to burn up all the powder before it left the barrel but now shorter barrels will do the same job but won't swing as well on birds but are handier in heavy coverts...
 
While true that that a 16" to 18" barrel is about optimum for velocity in most .22's, this is strictly about shotguns.

I would be interested in slug barrels and slug performance since seeing this. I assume the thing is that shotguns use relatively slow powders and accelerate the wad and shot the whole length of the barrel. Any stats on barrels GREATER than 30 inches? I would love to see that now that I have seen this. I know my old goose guns had some Long tubes on them!
 
As always barrel length will influence velocity. With some 22's if the barrel is too long the powder will burn up before the bullet leaves the barrel and will be faster from a shorter barrel.

If you look closely at the chart in the link there is really not a huge difference in any of them. Only around 50-60fps less from the 22" barrel when compared with the 28". Less than 15 fps in most cases when going to a 26" barrel.

The barrels with one * beside them have a turkey tube installed which adds 3" or so to the barrel and with two ** beside them are the published velocities, not the measured ones.

Barrel length should be chosen based on how the gun handles and points for you, and what you are going to use it for. While it is true a shorter barrel will almost always give up a little velocity, I'm not worrying about 15-50fps.
 
yes & no

jmr40
Barrel length should be chosen based on how the gun handles and points for you, and what you are going to use it for.
Click to expand...

I can easily agree with you now that I've seen the data that I was previously unaware of.


jmr40
While it is true a shorter barrel will almost always give up a little velocity, I'm not worrying about 15-50fps.
Click to expand...

On a skeet field, ducks decoying, quail hunting and early season doves I wouldn't worry about a 50-60 fps muzzle velocity loss either. On passing ducks at 50+ yards IMHO it would be a good time to start worrying.
 
The idea that a longer 32" or 36" shotgun barrel shot harder was a carry-over from black-powder days.

Still, 100 years or more later, it's a hard rumor to kill!

Fact of the matter is, that extra length past 28" - 30" is only slowing it down.

rc
 
I believe 12" is about the shortest you can go before velocity loss becomes a problem, it's not so that velocity drops off a cliff below that length but that IMO you're reaching a point where individual pellets might not have enough juice to do the job.
 
Most, if not all turkey tubes extend beyond the muzzle. You effectively turn the 28" barrel into a longer 29-31" barrel depending on the length of the turkey tube.
 
Yes, but if you will notice, the turkey tube velocities are even higher than the 30" barrel velocities. Most if not all turkey tubes are ported, and will negate any length once the wad is beyond even the first port.
 
The 30" numbers are manufacturers guesses. Not measured velocities, which I assume the others are.
 
I assume the thing is that shotguns use relatively slow powders and accelerate the wad and shot the whole length of the barrel.
Click to expand...

That would be a wrong assumption - shotgun powders are relatively fast, especially compared to rifle powders - why most shotgun powders also double as pistol powders
 
There is very little difference in velocity with a short barrel. Whatever fits you and you like, barrel length will not help or hurt your velocity enough to make a difference.

Velchart.jpg
 
Fast powders and slow powders are relative.. Compared to rifle powders they are fast, but also comparing Bullseye to Blue Dot, there are many powders in between.. Bullseye is nearly the fastest can grade powder sold, Blue Dot is one of the slower powders shotgun/pistol wise. Generally the faster powders like Red Dot, 700x, etc will work well in any barrel length, when you get to Blue Dot, SR4756, 800x, and the like, you will notice a lot more muzzle flash and the resulting less velocity than if you'd fired the same load with a longer barrel.

I'd call 1200, 1400 and 1600 fps a significant difference with a slug load. Muzzle energy difference with a 1 ounce slug is a difference of 1400 Ft/Lb energy (8" bbl) as opposed to 1900 ft/lb (18" bbl) and 2487 ft/lb of energy (28" bbl).

3" magnum loads generally use slower burning powders, and I'd say without a doubt that it makes some difference... though most hunters these days are hard pressed to use anything longer than a 28" or 30" barrel. My preference for years has been a 28" tube and to be sure what I'm getting, I chrono my hunting ammo to see if what the manufacturer claims, is what I'm actually getting. Kent Fast Steel claims 1550 fps and all of the ammo I tested from them is actually making 1570 fps plus in my gun (a few I've tested were over 1600 fps).
 
Status
Not open for further replies.

Similar threads

ssyoumans
  • Locked
Velocity vs. Barrel length
Replies
20
Views
11K
oneounceload
O
S
  • Locked
Speaking of barrel length
Replies
8
Views
1K
Dave McCracken
D
Z
  • Locked
Best All Round Barrel Length
Replies
9
Views
5K
Zerstoerer
Z
N
  • Locked
Shotgun barrel length and muzzle velocity
Replies
2
Views
774
A man with a gun!
A
N
  • Locked
Shortening a barrel: what are the disadvantages?
Replies
20
Views
4K
Leadhead
L
Back
Top