Bama, I have a Hawken built by Ted Jennings of the Hawken Armory out of Hot Springs, Arkansas. The 54 caliber rifle was made around 1982. It was sold to me as an authentic copy of the Hawken. The nose cap is screwed on with a flat head screw going through the stock wood and threaded into the nose cap. It saw heavy use the first 6-8 years I owned it with little use since that time. The nose cap has never shown any signs of working loose.
The stock profile, including fore arm, butt plate, butt stock, wrist etc., looks nearly exactly like the guns pictured in James D Baird's book "Hawken Rifles The Mountain Man's Choice. Whether the nose cap attachment method is authentic I cannot say with certainty, but it was represented as an accurate copy.