In the question about Jaeger/long rifle/plains rifle, you make some valid arguments but you are making an assumption about firearms and their place in society. You seem to think they were strictly a hunting tool. The fact is, people were then, as they are now, highly competitive, and they had not official organized sports such as we have today with basketball, baseball, football, bowling, golf and etc. Back then they had wrestling, knife throwing, a predecessor to bowling, and a few other competitions but nothing like today. The king of all competition sports, in the smaller villages, was shooting. The best shot was the local hero and the maker of his gun was at a similar position. They were the celebrities of the day. With this kind of competitive drive, even the smallest advantage would be utilized to improve ones chances.
The longer barrel does provide the advantage of both extended sighting radius and a better point of focus on the front sight. The further the front sight is from you eye, the more your eye can focus on both it and the target without either appearing blurry. These small, but not insignificant advantages would have been the edge that created the difference between the town hero and everybody else that owned a rifle. It wasn't just about hunting. Plenty of people put food on the table with smoothbores. It was about competition.
The old Jaegers were extremely heavy guns, and that may be due to older smithing techniques being questionable and the extra barrel thickness being needed to keep them safe. They would have made them shorter to keep them portable. The Plains rifles were designed to kill buffalo and grizzlies, as well as other game at a distance in the open country of the West. It was especially desirable for a grizzly to be hit with enough force that he was unable to pursue and kill his antagonist; but the longer range needed to kill game in open country also called for the ball to be smaller than many older guns, to make them flatter shooting. This meant more powder behind the ball. These guns had to have extremely heavy barrels, similar to the Jaegers, but for a different reason.
From original plains rifles I have seen, and not those just called plains rifles because they were half-stock, I would say they were just as heavy up front, having 34-38 inch barrels of a larger diameter than the 40-44 inch long rifles. These guns did not have the kind of steels or powder we have today and did not have the 26-28 inch barrel so common on what the call Hawken guns in the repro trade. Better target sights have also made the length of the gun less of an issue, although longer is still better until it gets too heavy for the shooter.
Additionally, men were stronger in those days, as well. The average man in the outlying communities spent all the daylight hours clearing fields, building cabins, farming with a horse drawn plough, and other activities that were much more strenuous then todays activities. For them, it would have been much easier to hold the long or heavy barrels found on so many of the older guns.
I am sure there are other reasons than these, but these seem to me to be the most obvious reason for the long rifles. Of course someone could make a crude remark about the length of some part of the anatomy being represented by the length of the rifle, but I certainly wouldn't. That would definitely cause an argument. :grin:
OTOH, I have held Jaegers that were marvels of design and balance.
