The RCBS Grand and Mini Grand Shotshell presses were designed for the shotshell reloader looking to load accurate, precise shotshells. These powder bushings are identified by numbers that correspond to the size of their inside diameter. (For instance, the inside diameter of the #456 bushing is .456").
Always verify the powder charge weight with an accurate scale. Weights may vary significantly from the chart listings.
For best results, choose the bushing needed and then purchase it and the next number higher and lower bushing. Hornady
and RCBS bushings are interchangeable.
For use with RCBS The Grand and Mini Grand shotshell reloading press plus these will also fit Hornady and Posness Warren presses.
How to select bushing for half grain charges:
Powder bushing are identified by numbers that correspond to the size of their inside diameter. (For instance, the inside diameter of the number 456 bushing is .456 inches). Bushing for powder charges in half-grain increments can be calculated from this chart. Simply "split the difference" between the two even-grain bushings and select bushings nearest the result.