# Batch 2018-batch-01 # A slightly improved "repeat performance" M reload for my CTI Pro75 6xl case with Loki nozzle and forward closure. Using Terry's #50 "short" Loki nozzle, we need a 38" liner and have just under 37" available for fuel. Using dash-143 buna-n o-rings as grain spacers, let's try 7 grains of 5.205" length, or 132mm, using Delrin coring rods of 0.75" diameter. This will be slightly more progressive than the 8-brain config last fall, but all parameters look good and it's a tad more propellant due to one less inter-grain gap. The simulator says this could be a 34% M-2593. Based on previous experience, there will be enough shrinkage to necessitate a "topping up" of each grain after the initial pour cools. The simulator says we need 4919g of fuel for these grains, so let's melt a batch size of 5kg: * 65% KNO3, 3250g * 35% Sorbitol, 1750g * 1% red iron oxide, 50g, added after melt * 75 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 . ## Results ## Average casting tube weight g. * 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 * Grain 7, g gross, g net Total propellant load g. Revised simulation says this will be...