I'm curious what your opinions are on the capabilities of a 50# longbow on all of North Americans big game animals. Does it have enough "juice" to ethically take down even the largest moose or bison?
The original poster to start this thread has asked a simple question that requires a highly complex answer. More specifics are needed in his question to render a proper answer. A 50# home-made self bow differs substantially from a (insert professional bowyer's name here) in a reflex/deflex sophisticated design or even that of the ILF designs. The modern designs simply render more efficient use of the energy stored within the machine (bow).
This original question is a question that has been beaten to death many times
. Obviously doing the research from prior threads on Tradgang should have answered his question in the affirmative.
In addition to the type of 50# long bow arrow build and proper tuning will play a substantial factor in this equation, as will choice of broadhead design. Much of his answer can be found in reading the extensive Ashby research posted in the Topic Archives on the Trad Gang forum.
With respect to the animals cited, Moose are not a particularly difficult animal to penetrate in that they are not built with any armor like that of Cape Buffalo. We have several TradGangsters from Alaska whom have reported in threads on their successes in harvesting Moose with lighter bows. Bison have been killed for thousands of years by native Americans using stone points and typically using 40 to 50 lb. self made bows. These bows would not hold the degree of sophistication that our modern bowyers employ daily to produce far more efficient machines than those used by our Native American brethren. As for dangerous game like the large coastal bears they too hold no outstanding armor in the vulnerable rib areas. Their armor tends to be in the cranial cavity. I know of no knowledgeable hunter whom would intentionally shoot for the head of a coastal bear. The most difficult North American animal to penetrate may well be the large mature boar hogs with the grizzle armor in their shoulders. Using proper shot placement, arrow build & tuning, combined with broadhead selection has been proven to harvest even these "American Rhinos".
Basically the most important component is not necessarily the use of a 50# Longbow to harvest the largest species of American big game but rather how much talent and knowledge of his/her equipment does the nut who's holding onto the 50# long bow possess. So....the short answer to the original poster's question is: Yes, so long as the nut holding onto the bow has done his/her part.