# Batch 2017-batch-04 #
-4 grains of 29mm using sorbitol, intended to be a reloads for the
-second-longest GMA 29mm snap-ring case. Grain length 45mm with 1mm spacing
-per grain, so we'll make the casting tubes 46mm long. Delrin coring rods of
-5/16" diameter.
+4 grains of 29mm intended to be a reloads for the second-longest GMA 29mm
+snap-ring case, *and* 6 grains of 54mm intended to be 2 3-grain reloads, all
+in one sorbitol melt.
-Formula for a batch size of 135g:
+29mm grain length 45mm with 1mm spacing per grain, so we'll make the casting
+tubes 46mm long. Delrin coring rods of 5/16" diameter.
-* 65% KNO3, 87.75g, taken from the big bucket
-* 35% Sorbitol, 47.25g
-* 1% RIO, 1.35g
-* PolyStep B1, 2 drops
+54mm grain length 76mm with 2mm spacing per grain, so we'll make the casting
+tubes 78mm long. Delrin coring rods of 1/2" diameter.
+
+Formula for a batch size of 1kg:
+
+* 65% KNO3, 650g, taken from the big bucket
+* 35% Sorbitol, 350g
+* 1% RIO, 10.0g
+* PolyStep B1, 15 drops
+
+With left-overs from batch-01, this was enough for all but two of the 29mm
+grains. We added enough materials for another 100g and were able to finish
+up with a bit left over.
Presto Multicooker operated at 275F indicated.
## Results ##
-Average casting tube mass 1.25g.
+Average 29mm casting tube mass 1.25g.
-* Grain 1, ?g gross, ?g net
-* Grain 2, ?g gross, ?g net
-* Grain 3, ?g gross, ?g net
-* Grain 4, ?g gross, ?g net
+29mm grains
-Total of ?g propellant, vs 122g simulated.
+* Grain 1, 29.3g gross, 28.05g net
+* Grain 2, 29.1g gross, 27.85g net
+* Grain 3, 28.9g gross, 27.65g net
+* Grain 4, 28.5g gross, 27.25g net
+
+Total of 110.8g propellant, vs 122g simulated.
With a 7.40" liner, 14/64" nozzle throat, buna-n o-rings, simulation says
this reload will be a 99% G-180, 159 Ns, with about an 0.8 sec burn.
+54mm grains
+
+* Grain 5, 184.6g gross, ?g net
+* Grain 6, 183.3g gross, ?g net
+* Grain 7, 186.2g gross, ?g net
+* Grain 8, 182.6g gross, ?g net (canted - casting tube tilted at pour time)
+* Grain 9, 184.0g gross, ?g net
+* Grain 10, 180.5g gross, ?g net
+