Re: Looking for advice on 1 lb. bp rocket delay comps

Historically the massif, or solid portion of the rocket's rammed
composition (which the original poster is, I'm assuming, referring to
as the "delay") was always made with the same mixture as the gallery,
or hollowed portion. One to 1-1/2 diameters is usual. There's really no
reason to make the massif out of another composition unless another
effect (e.g., tremolante or falistrante tail) is wanted.

I suspect that concern about using a different, slower composition
arises because some suppliers make their spindles too long, and the
space remaining in the case for the massif is not enough to ram enough
of the main composition to give a proper delay, plus a clay plug. In
such a situation I'd sooner just shorten the spindle! If this
necessitates an adjustment in the formulation, so be it. For a standard
rocket case 10 ID's in length (e.g., a 3/4" or American 1-lb. case will
be 7-1/2" long), the hollow left by the spindle need be no more than 7
diameters in length. Allowing 1 ID for the base of the spindle that
still leaves 1-1/2" from the tip of the spindle to the top edge of the
case, which is plenty of room for the massif.

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