When I sighted my Franchi for slugs, I could only find hot hunting slugs and wanted an idea of where they hit at 100.
Shot 3 rounds off a bench and said "it better be close because I ain't doing much more of that!" Very very stiff recoil. And it's a 26".
Promptly turned to my buddy and said "you have to try this. You gotta feel how soft this gun shoots!" lolz.
But generally a lot of people use those Fiocchi low recoil slugs, or similar. And a lot of regular bird shot gets used. So not a ton of recoil. But the Benelli M-2 type guns thump quite a bit over the gas operated guns. Just my non-expert opinions.
This reminds me of a fun story....
Years ago, after I'd converted my Saiga 12 to Pg and traditional stock I was out shooting with a friend.
I'd been running it hard, and broke out a few 5rd mags worth of 3in mag slugs and was having a blast.
My friend decides he wants to shoot it, so I hand him the gun, and ask if he wants want I had been shooting... he says yeah!
I load up a 5 rd'er with the same 3in mag slugs ( IF I recall, they were 1oz at 1800, or was it 1900 fps?).... he locks in the mag, lets the bolt rip, and pulls that trigger.
The look of *OW* was incredible. He fires again. And again. And once more. And he hesitates. And fires once again. At this point he looks pained.
And he lifts the gun up, lines up the sights, and pulls that trigger one more time.
*Click*! Followed by the most intense look of relief. He hands it back and tells me never again.