2 3/4" shells in 3" chamber?

[Big]

The barrel of my new H&R 20ga slug gun is marked "3 inch rifled bore."  Is it OK to use 2 3/4" slugs?

[kynardsj]

Yep. If you do it a lot it will take some cleaning to chamber a 3 inch shell. Like shooting a bunch of 38's in a 357 mag. You have to clean it before it'll shoot the longer ones.

[DeerSlayer777]

I do it all the time and never noticed any more fouling than the norm.

[Big]

Thanks, guys. 

[alleyyooper]

Thats what was recommended for my 870 slug gun using buck hammers. Was told the 3 inch buck hammers didn't work to well in it.
 
    Al

[SHOOTALL]

Yep. If you do it a lot it will take some cleaning to chamber a 3 inch shell. Like shooting a bunch of 38's in a 357 mag. You have to clean it before it'll shoot the longer ones.

why ? when a 2 3/4 shell opens when fired it is close to if not longer than a 3 inch shell before fireing so there should not be a crud ring until past 3 inches into the chamber if at all . Even a roll crimp extends out upon fireing .
I have found that 3 inch shells shoot better in 3 inch chambers with reguard to slugs , it may be due to a longer free bore which may allow a bit of yaw before entering the forcing cone .

[KIMBER45]

I only use 2 3/4 inch in mine. I don't need the extra recoil of the 3 in. ouch !!!