Longer barrel equals tighter pattern??

[roundball]

I read some posts or an article somewhere that claimed with all else equal, a longer smoothbore barrel would give a tighter shot pattern.

ie: 32" vs. 38" cylinder bore...the 38" would produce a tighter shot pattern.

Anybody have any actual hands on experience or official reference documentation to know if thats an across-the-board fact and not just an old wives tale? 

[Harnic]

RB, it's the truth!  A longer barrel will shoot a tighter pattern, all else being equal.  That's because the powder charge will be more thoroughly consumed, reducing the pressure behind the wad.  With no choke in place, the shot charge tends roll off the wad as it clears the muzzle & the more residual pressure behind that wad will push the wad through the shot column, spreading the pattern even more.  That's why really long barrels were/are much more popular with smoothies than rifles.

[Leatherbelly]

Hey,
 Makes sense to me.
 Hi Harry,how's it hangin'? Still got that barrel boring and rifling scratching machine? Or is that the one that Hughy Toenjes has now? May want a loooonnngg barrel soon.

[Harnic]

Hi LB!  Ltns!  Doing really well here ty!  How's it going there?  No, I don't have that rifling bench, it is the one Hugh has now.  I only did a dozen barrels with it in 1980 before I realized it wasn't going to be a profitable venture & it kept me away from more important bench work.  Sometimes I wish I had another, I could open my barrel up to 58 or 62 & lighten it  a tad!    Cya at Heffley!

[M. Wheland]

I have built fowlers with 38" to 44" Barrels without seeing a big difference in pattern size.
I noticed the affect of the longer barrel after building one with a 57" barrel.
They do shoot tighter patterns !!!

Mark

[northmn]

Interesting concept.  A 56 inch barrel may prove slightly unwieldy (they did build them that way I know)  You can get some variation barrel to barrel and shot size to shot size.  I have had barrels that did not like certain sized shot (in a standard load) for instance.  Whether its true or not I really wouldn't argue.  Things that do not hold for smokeless powders held for black.  It would be a turkey issue more than one of wingshooting where the gun has to be swung on target.

DP

[Daryl]

Some double shotguns had barrels up to 48" long.  They were well known as strong shooters, even though cylinder bored. Harry's spot-on concerning the drop of pressure at the muzzles being the reason - in my opinion.  Comon Horse Sense prevails here.
Now, properly choke that gun and you can have a strong shooter with even 26" barrels.