Many rests used in RFBR, one of two piece, come with a single adjustable aluminum "front post" for return to battery/stop. I've noticed some have Delrin sleeves or other materials (O-rings, rubber, etc.) added by the competitor. Some have two posts that rest against the stock on either side of the barrel, referred to as goal posts.
What works best for you as a competitor? John
What works best for you as a competitor? John