BSA air rifles are a new name to me. I’ve always been familiar with Crosman, Gamo, Umarex, Benjamin, Beeman, Daisy, etc… but not BSA.
When someone mentions BSA, I think of rifle scopes.
BSA apparently makes some really nice, high end air rifles. BSA air rifles are made in the United Kingdom. Prices range from $150-$1200.
Anyway, here is a video describing the rifled barrels that are used in BSA Air Rifles. If you’re interested in how air rifle barrels are made, you’ll love this video. It’s quite interesting.