Whenever I am catching beaver I always question how much I should vs. how much I could stretch a beaver. There doesn't seem to be a real clear guideline for exactly what is "proper" and what is just flagrant stretching trying to reach the next size. Below are two of my examples:
The beaver on the left I consider to be properly stretched. There are still some stretch marks in the head half of the hide but those go with the territory if you stretch a beaver to the same ring all the way around. Which brings up a second point, should the oval we stretch beaver to have a head and tail end? It seems like the head end of every hide is slightly smaller than the tail end. This might be beyond the realm of this board though...
The beaver on the right I probably guessed a little bit wrong and realized I had it too tight on the board after it was halfway to being nailed down. The stretch marks are obvious and to me, the hide looks bad. I know some trappers who stretch every beaver so tight that the entire hide is white from stretch marks.
So what is the proper stretch? Should prime, winter caught beaver be stretched as tight as you can manage? Should you go for a snug fit that gives you a hide with few to no stretch marks, much like the top beaver?