It is a plane on a device, on which the bolt head pushes (when the bolt gets screwed)
for example: on a frame at a bike, there are no planes. When a bolt shoulb be assembled there will be madea plane just for this bolt bolt. the bolt boss
it could be, that this word just emerges from a translation out of the German language.
It can be done.
Allows for adjustment of barrel harmonics.
try customer service at browning.com
50-550 usd
Try midwestgunworks.com
500 USD
Cleveland heads...
This site will answer your question: http://www.browning.com/customerservice/qna/detail.asp?ID=107
You have to experiment with different settings and ammunition.
@ 400 USD
100-1000 USD depending on specifics
Boat. Boar. Boil. Bogs. Bone. Bomb. Bolt. Bold. Bond. Boss.