There are two CVA Stag Horn rifles.
1. The older rifle has a two piece barrel/receiver. Do not exceed 100 grains of BP or Pyrodex in this gun.
2. The newer CVA Stag Horn has a one piece barrel and receiver. It is good for 150 grains of BP or Pyrodex.
3. There are two breech plugs for those rifles. One breech plug is for 209 primers. The other breech plug accepts #11 or musket cap nipples.
Do not attempt to use BH 209 powder in those guns.
Both breech plugs are shown here:
https://www.midwayusa.com/black-powd...s/br?cid=23209