STRAIGHT WALLED CARTRIDGE

The council also approved straight-walled cartridge rifles for deer hunting. The rifles are the same caliber and use the same straight-walled cartridges that are currently legal for use in handguns. The new regulation is designed to allow additional opportunities for hunters that own these guns or want to hunt with these guns. These rifles have reduced recoil compared to larger shotguns, and the rifles are more accurate than the same caliber handgun.
Legal deer hunting rifles are chambered for the following calibers: .357 Magnum, .357 Maximum, .38 Special, .375 Super Magnum, .375 Winchester, .38-55, .41 Long Colt, .41 Magnum, .44 Special, .44 Magnum, .444 Marlin, .45 ACP, .45 Colt, .45 Long Colt, .45 Winchester Magnum, .45 Smith & Wesson, .454 Casull, .460 Smith & Wesson, .45-70, .45-90, .45-110, .475 Linebaugh, .50-70, .50-90, .50-100, .50-110 and .500 Smith & Wesson.
 
Source: ODNR.
 

That was true back in the old days before AR/HR. With these world class whitetails we have now you need all the firepower you can handle.

A 12 gauge slug gun shooting Foster or Rifled slugs, which are commonly 1 oz (~440gr) or 1 1/4oz(~550gr) slugs, are every bit as much of a cannon, and in many cases more of a cannon than the straightwalled cartridges listed above.  And as I'm sure most are already aware, 12 gauge slug guns have been the firearm of choice for deer hunting in Ohio (and here in Allegheny Co.) for many years now.  When I look at the capabilities of the very popular 30 caliber and 7mm magnum platforms used in PA, I have a hard time calling slugs or straightwalled cartidges cannons.   
 
For the most part, these straightwalled cartridges are fairly obscure calibers and in many cases these are more nostalgic type calibers.  They really don't come close to comparing to the ballistics of a modern rifled slug or in-line muzzy and in general are low velocity (<2000fps) guns shooting heavy bullets (300-500gr) .  Of the bunch, the 45-70 probably will be one of the more popular choices and has better ballistics than most of the available options, but even with a good load it will still perform similar to a 12 gauge saboted slug. 
 
I don't see many people jumping to straight walled cartidges because there really isn't any performance advantage to doing so.  Although my Dad, who seems to think he is still a cowboy, may be out there chasing deer with either the 45-90 black powder or 45 Long Colt rifle, both equipped with peep sights         

Ballistics for the 454 are certainly more than adequate for hunting, but not all that impressive when compared to most common centerfires we use here.  A 300 gr bullet fired at around 1500-1600 fps would be a fairly typical hunting round.  But, I do agree that it would be a handful out of a revolver and I have no desire to ever do so.  They do make some lever action rifles in 454, but I don't think they are very popular.  Probably because of the 45-70, which performs better and has much more commonly available ammo. 
 
I've never shot either, but from the looks of it the 500 S&W would be the real monster to shoot out of a handgun.  Something about shooting 500 gr bullets out of a revolver just doesn't sound all that pleasant to me.  Basically, it would be like shooting a supercharged 12 gauge foster slug out of a 4 pound revolver.  No thanks!      

pikepredator2
 What's so different about the straight walled that makes them ok to use now but not a cartridge with a shoulder or belt?

Perception. 
 
Pa did a study about the possibility of expanding the shotgun only areas. It was determined that slower moving projectiles are actually more dangerous than high velocity projectiles. Because of this, it was not recommended that the shotgun only areas be expanded.