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[web/gag.com] / rockets / research / 2017-batch-06.mdwn

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+# Batch 2017-batch-06 #
+
+8 grains of 54mm using sorbitol, intended to be 2 reloads for the longest 
+54mm snap-ring case currently in our possession, and/or some mix of lesser
+loads.  Grain length 76mm with 2mm spacing per grain, so we'll make the 
+casting tubes 78mm long.  Delrin coring rods of 0.5" diameter.  
+
+Formula for a batch size of 1750g:
+
+* 65% KNO3, 1137.5g
+* 35% Sorbitol, 612.5g
+* 1% red iron oxide, 17.5g, added after melt
+* 25 drops Polystep-B1, added before pour using eye dropper
+
+This formula is completely fluid with 225F indicated on the Presto Multicooker,
+but viscosity is noticeabley lower making for easier pouring at 250-275F.
+
+These grains were cast on 28 September 2017.
+
+## Results ##
+
+Average casting tube weight 5.90g.
+
+* Grain 1, 188g gross, ?g net
+* Grain 2, 182g gross, ?g net
+* Grain 3, 188g gross, ?g net
+* Grain 4, 184g gross, ?g net
+
+* Grain 5, 178g gross, ?g net
+* Grain 6, 190g gross, ?g net
+* Grain 7, 182g gross, ?g net
+* Grain 8, 186g gross, ?g net
+
+With a 13.250" liner, 8.9mm nozzle throat, buna-n o-rings, simulation says
+this makes a 39% J-597, 1050 Ns, with about a 1.5 sec burn
+