You will need a thrust ring for all Black Powder motors. I would set the thrust ring for the longest BP motor on the market, that way you can use a spacer for shorter BP motors on smaller fields.

With the 24mm center motor setup. If that is the case, then what I just mentioned works best. Set it up for E motors, use spacer for D motors, and it will still work for aerotech motors to.

Aerotech reloads have a lip, so you don’t need a thrust ring with them. Also, you could put a 1/8” ring of tape on a BP motor,s aft end and build it up so it want slide all the way into the motor tube and not glue in a thrust ring if you want.

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If the Sky is the Limit, then,
why is there Footsteps on the Moon?
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