I lived 9 miles from the unit for 27 years, You are headed in the right direction when talking about Radersburg. I have seen numerous 400+ bulls in this unit, ESPECIALLY when the snow gets deep.
To my knowledge, there's been two bulls taken in the Elkhorns in the mid 390's, one of which was shot in the mid 1950's. I've been lucky to have this tag three times and I've assisted my hunting partners on four other tags. I've been hunting (horn hunting too) this unit for 15+ years and the biggest bull I've seen during season would be in the mid to high 380's. I'm not saying there isn't any 400 class bulls, but this unit is plentiful with 300-320 class bulls. I highly disagree there are numerous 400+ bulls.
After having the tag last year for the third time I had two goals:
1) harvest a 340+ bull......easier said than done!!!!!!
2) don't allow anyone to out hunt me
I had PLENTY of chances last year and I was easily getting frustrated because the majority of the bulls are 300-320. The Elkhorns are a blast to hunt, but DON'T expect to see 340+ bulls on a normal basis.
By the way, I just received a returned letter from the biologist for the Elkhorns letting me know the age of my elk which he was 7.5 years. I was informed from the biologist the average age of the bulls harvested during the 2012 season was 7.1 years old. There was 3 bulls harvested at 11.5 years and 1 bull harvested at 14.5 years.
Good luck with the tag!!!!
Send me a PM and I'll assist as best as I can. I have a handful of areas that will be easy for you and your kids to hunt.