Hey. New to the community but not to H&R or Nef. I recently purchased a Huntsman 50 cal barrel with the extendable ramrod. This barrel has the screw type holder for the forearm. I want to adapt it to either the sb1 or sb2 frame but can't figure out which forearm I need. I am also considering adapting this barrel from the original primer carrier to the 209 nipple. Anybody got any information that would help?