Other barrel testing coming. At this time, we do not expect these to work in original smooth twist FX barrels but should be OK in the new Slug X barrel by FX if the barrel likes .217 sized slugs (this slug not available in .218).
Do not buy these or any slug for standard smooth twist FX barrels.
These do work in Smooth Twist X barrel SLUG liners.
Length is .253
Diameter available in this slug: .217
NO RETURNS WHATSOEVER!