Shotgun velocity question

venatic

venatic

Well-known member
I happened to see on another forum a discussion about shotgun barrel length.
It was mentioned that shotgun pellet velocity was actually faster from the shorter 18-21 inch barrels vs say 26-28 inch barrels. I want to continue my streak of not ever shooting my chronograph so can someone check that out and get back.
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GC I did do a little..very little reading on the shotgun sticky but I did not see mention of speeds. It may be common knowledge and the reasons given sounded reasonable and came from someone who said they had done the testing and heck it was on the internet .....but it could be some misinformation put out by the NSA.
 
I thought the only real reason for longer barrels was to have a longer sight radius, and a side benefit is they are not as loud for others if you're in a stand.
 
I would have to agree with Bernie P. With the same primer and exact same load and powder charge (plus or minus a wee bit of powder because im sure manufactured loads aren't measured with consistency as hand loads are) I don't see how barrel length can change speed. if you crono them the only speed difference should be due to inconsistent powder charges being a hair off. I could be wrong but that's the sense I make of it. I thought longer shotgun barrels only purpose is to get a tighter grouping at greater distances. If that wasn't true then why are all the waterfowl barrels mega long? if they could get the same pattern with a 20" vs a 28" every duck hunter would have the 20" due to its easier to swing around all day.
 
Generally speaking the longer barrels might tend to pattern somewhat better and will give slight increases in velocity. The velocity thing is very slight, like maybe 5 fps per inch of shotgun barrel depending upon the load. With field loads there is less of a difference than with a heavy magnum type load. A heavy magnum load will usually gain a bit of velocity in a longer barrel. A tighter choke can even affect velocity and usually chronographs slightly higher than a less restrictive constriction of choke. All that is however a pretty insignificant difference. This makes the velocity factor pretty much a non-issue when considering common hunting lengths like the difference between a 23" turkey specific barrel and a 26" wingshooting/general use barrel. For predator or turkey specific I really like 24" barrels with a close second being a 26" length.

Patterning is much the same kind of deal. The differences in individual barrels and chokes and how they react to a certain load can negate any advantage length may play in giving a better pattern. As an example, I have 18 ½”, 24", and 26" barrels for my two Benelli M1S90 semi-auto 12's and they all take the exact same chokes. The 24" and 26" are pretty much even in pattern densities with no clear advantage to either one. Most of the time both of those two will out pattern the shorter 18 ½” barrel. Sometimes by a great degree, sometimes by not so much. However, in at least one instance the shortest barrel will out shoot the other two with a certain load and choke. Which reminds me that there are no set hard and fast rules and I always try to speak in general terms.
 
Originally Posted By: brusso89 I thought longer shotgun barrels only purpose is to get a tighter grouping at greater distances.


This has been proven not true. Patterns are not directly conected to barrel length. As said, longer barrels are easier to shoot because of the long sight plain...

However, I'm not sure about the velocity difference in venatic's post. I know in rifles, the longer barrel is faster because the gases keep expanding. I would "think" that would hold true in shotguns but I'm unsure. I doubt the difference (in speed) would be as much (as in rifles, ~20-25 fps per inch) as the pressures are much less in the shotgun load...

 
brusso,
Modern era waterfowl hunter’s use of long barrels has little to do with practical patterning ability. Old timers with their "Long Tom" shotguns did see better patterns and even higher velocities from extra long barrels. Modern choke tubes and more efficient shotshell powders and wads have evened the field concerning barrel length and how it relates to patterning and velocity.

With that said, long barrels have a very decided advantage in sight plane and smooth swinging ability on fast moving aerial targets. Whether using the sustained lead or pull through methods a long barrel smoothes the swing, tracks more evenly and follows through considerably better than a stubby shotgun barrel. Go shoot a sporting clays course with a 20” barrel and then with a 30” barrel and see which one you score higher with. The pros in the clay target games have moved to 30” 34” shotgun barrels for a reason.
 
Longer barrels tend to shoot better...because you have a better sight picture/plane.

Turkey guns tend to have a shorter barrel because they're not swinging on a turkey, but aiming ultra tight patterns.

As for the speed thing, I don't think there is enought gains/loss to worry too much about barrel length for speed alone.

I do like 28-30 barrels for swinging targets, myself.
 
Quote:With that said, long barrels have a very decided advantage in sight plane and smooth swinging ability on fast moving aerial targets. Whether using the sustained lead or pull through methods a long barrel smoothes the swing, tracks more evenly and follows through considerably better than a stubby shotgun barrel......I would agree with GC on this one...

Having been trained with 18-19" riot gun barrels as a LEO and then shooting Sporting Clays with the longer barrels, the accuracy factor and follow through capability of the longer barrel (28-30") is a definite plus...

I have to admit that when I'm shooting Clays in the 5-stand situation where the 'birds' are closer and moving with the perception of being faster, the shorter barrel lets me score a little higher, just because I can swing it faster, but on the regular open field course, my scores drop with the shorter barrel...
 
I don't know what the speed difference is between short barreled shotguns and long barreled shotguns.

The velocity of shotgun pellets is not nearly as important as the velocity of rifle bullets. Round pellets do not hold their speed like bullets do, round pellets slow down very fast. The faster they start out the faster they slow down.

On some of the real fast shotgun loads the manufacturers will say that you will need 6" to 8" less lead on a fast target with their high speed loads. On real fast long range targets that require leads from 8 ft to say 14 ft a 6" to 8" shorter lead won't help you much.

Longer barreled shotguns with barrels up to 34" long are taking over on the shotgun clay target sports because they do swing so much smoother than short barreled shotguns. Quite a few of the shotgun shooters that shoot Trap, Skeet and Sporting Clays prefer the heavier shotguns with longer barrels over lighter shotguns with the same length barrels because the heavier shotguns swing even smoother.
 
I read somewhere that the gas pressure is low towards the end of the barrel as evidenced by how thin the barrel is at the end compared to the chamber. Also that's why shotgun porting doesn't really work like a rifle muzzle break, there isn't enough pressure. They still make noise though.
 
When coyotes sprout wings and start flying as fast as a dove I'm going to use a 28 or 30" barrel. Until then I think a 24" is gonna work just fine. Soooooo much handier.
 
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I can't remember where this came from, but when we checked the velocities on our SBS compared to longer barrel lengths, they were very close. I can't find my numbers currently.
 
Good thing I checked back on this thread! I stated I "thought" a lot and I was wrong! some good to know info. I have never tried shooting clays or hunting with short barrels I just "thought" they would be easier to swing around due to it being smaller and lighter but heard their pattern was super wide (maybe because most short home defense barrels aren't threaded for chokes??) so they wouldn't be good for hunting. I totally believe all you guys but just for poop and giggles im going to have to attempt it sometime just to say I tried.
 
Many trap/skeet ranges won't allow short barrels. It makes the lifetime members with $3,000 shotguns jealous when you beat them with your cheap pump Rem 870 18" barrel.
 
When I had a shotgun barrel (36"), made to fit my Moss 590A1 to use as a switch barrel, Howard Montgomery (builder), told me that after about 34" the shotwad begins to slow, and you don't even need a choke as long as the barrel I.D. is consistent through its length. He builds the long 48" barrels for card shooters to get the real tight patterns.
 
So cylinder bore patterns as tight as any choke tube as long as the barrel is over 34"? I ain't buying it...
 
I just now got back to this post and the picture above was very interesting.

I went back and found the post and here was his reasoning which sounded plausible. Having never chronographed a shotgun I just assumed they were like rifles but obviously velocity wise longer don’t get you much to speak of.

This is a quote from the post.......... This seems to validate what some others have posted above.

"Well here is why. The gas coming out of the barrel move much faster than the shot. If the barrel is shorter say around 18" it can and does shove the wad, which has already released some of the shot as it has traveled down the barrel from 13" TO THE 18" mark, through the shot collum causing more pattern dispertion, even with the same chokes comparetivly. What the longer barrel does is actually start the wad slowing down which more gently releases the shot. In general longer barrels will give denser patterns for the same choke, not "more velocity". I know, I know, but I HAVE chronoed lots of shotguns and lots of barrel lengths. Internal ballistics play a huge roll in shotguns, and longer DOESN'T mean more velocity But hey all you got to do is chrono for yourself!"
 
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