# Batch 2017-batch-03 # 6 grains of 29mm using erythritol, intended to be a reloads for the longest GMA 29mm snap-ring case. Grain length 41mm with 1mm spacing per grain, so we'll make the casting tubes 42mm long. Delrin coring rods of 5/16" diameter. Formula for a batch size of 175g: * 65% KNO3, 113.75g, taken from the big bucket * 35% Erythritol, 61.25g The multi-cooker was preheated to about 250F with the lid on. Temp was increased during melting to 300F indicated. These grains were cast on 31 May 2017. Simulation says:

29mm 6-grain Erythritol #14
Rating:	43% H-162	Max Pressure:	5.92 MPa (859 psi)
Total Impulse:	216 Ns	Specific Impulse:	133 s
Max Thrust:	206 N	Volume Loading:	70%
Average Thrust:	162 N	Fuel Mass:	165 g

## Results ## Average casting tube mass 1.13g. * Grain 1, ?g gross, ?g net * Grain 2, ?g gross, ?g net * Grain 3, ?g gross, ?g net * Grain 4, ?g gross, ?g net * Grain 5, ?g gross, ?g net * Grain 6, ?g gross, ?g net With a 10.00" liner, 14/64" nozzle throat, buna-n o-rings, simulation says this makes a 37% H-156, 208 Ns, with about a 1.2 sec burn.