If bore size defines "Thumper", then there are the pump and lever action rifles in the 357 mag, 44 mag, and 45 LC pistol cartridges. But, if you mean "thumper" as a term to indicate a rifle for large game, then other reasons for longer actions include slimmer magazines and higher capacity magazines, because the rounds are not as fat.
Is there a psycho babble conection between fat hunters and fat cartridges?
Now thats funny!!!...for me I just like pondering things. Do I have a need for a short action big/dangerous game rifle? Not at all. I have a 9.3x62, 300 win mag, 2 45-70's 2 30-06's a 35 Whelen and a 270wsm. The 270wsm is a MRC1999 in a Mcmlillan stock. Nice rifle just not crazy about the caliber so I started day dreamin. If Ruger would come out with the Alaskan in 375 Ruger for lefties id own one. My main rifles are the 30-06's and the 9.3...the rest are just for fun. If someone twisted my arm I would love to play with a wsm wildcat but thats just because I can...great thread, thanks all.