2 3/4" velocity drop in a 3 1/2" chambered gun?

[A.SCHULTZ]

I'm curious if there is a significant drop in velocity when you shoot 2 3/4 shells or 3" shells out of a 3 1/2" chambered gun. Has anyone ever seen anything published or chronographed it themselves?

 

[rembolt]

Chamber lenght will have NO effect on the velocity produced by the shell.barrel length will have some effect on velocity but for the most part is neglegable.

 

[gunsaholic]

Should make no difference.

 

[3macs1]

Chamber lenght will have NO effect on the velocity produced by the shell.barrel length will have some effect on velocity but for the most part is neglegable.

X2. Some say it is 5 fps / inch after 24" which is not worth talking about

 

[brybenn]

I just tried my loads. They're consistent at 1295fps. Fired in my sxs's. My 3.5" pump tested and ave of 1287fps as of just now

 

[rembolt]

I will bet there is a difference in bore diameter between the two guns .also are the barrels of equal length

 

[3macs1]

I will bet there is a difference in bore diameter between the two guns .also are the barrels of equal length

Or bore finish or relief angle on forcing cone or choke tolerance, many items for such a small difference

 

[Bigbubba]

8 fps at 1295 is not significant at all........0.6%

the chamber has no effect

 

[brybenn]

Barrels are 28" for the pump 28 5/8" for the sxs. Not much difference