Description RCB Group D Expander Decapping Unit .30, Expander Decapper Units For expanding and belling the case mouth and removing the primer from the case. Firearms, trailers, and some accessories are only available for purchase in stores. Each location follows all BATF and individual state/county/city laws to insure the desired product is legal for sale. Any info provided online is subject to change, please go to your local store for more accurate information.