Slugs in 3 1/2" chamber?

[DBR]

Does shooting 2 3/4" 12ga slugs in a 3 1/2" chambered barrel affect accuracy because of the long jump to the forcing cone?

 

[.45 AUTO]

Not in my experience they don't, I have a Remington 870 Express Super Magnum and I shot some 2 3/4 slugs and they were right on. They were just as if not more so accurate than the 3 in slugs I fired.