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Solid Rocket Propellant
Formulation Data

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This page lists propellant formulation information not available in the "How To Make Amateur Rockets" book. The propellant parameters will be adjust from time to time to provide a more accurate characterization as more motor firing data on a particular formulation becomes available.

Initial weights are shown based on total propellant weight. The second set of weights shown in brackets are based on the weight of the propellant less the binder weight as discussed in the "How To Make Amateur Rockets" book. The curing agent ratio is shown for the second set of weights.


    Propellant 1
  • 19.27% (20%) R20LM HTPB
  • 19.27% (20%) Magnesium powder(-650 mesh)
  • 57.8% (60%) Ammonium Nitrate powder
  • 3.66% (Curing ratio = 0.19) Rubinate M MDI Curing Agent
  • Burn rate coefficient = 0.0061
  • Burn rate exponent = 0.507
  • Propellant density = 0.0527 lbm/inch**3
  • C-star range = 4100 to 3300 feet/second depending on motor size.
  • Gamma = 1.23
    Propellant 2
  • 19.27% (20%) R45HT or R45M HTPB
  • 19.27% (20%) Magnesium (-650 mesh)
  • 57.8% (60%) Ammonium Nitrate powder
  • 3.66% (Curing ratio = 0.19) Rubinate M MDI Curing Agent
  • Burn rate coefficient = 0.0032
  • Burn rate exponent = 0.6
  • Propellant density = 0.0527 lbm/inch**3
  • C-star range = 4100 to 3300 feet/second depending on motor size.
  • Gamma = 1.23
    Propellant 3
  • 19.27% (20%) R45HT or R45M HTPB
  • 9.64% (10%) Aluminum powder (-400 mesh or 20 micron)
  • 67.43% (70%) Ammonium Perchlorate (200 micron)
  • 3.66% (Curing ratio = 0.19) Mondur MR MDI Curing Agent
  • Burn rate coefficient = 0.038
  • Burn rate exponent = 0.31
  • Propellant density = 0.056 lbm/inch**3
  • C-star range = 4448 to 3540 feet/second depending on motor size.
  • Gamma = 1.23

Note: Curing agent ratio = (Wt. of curing agent)/(Wt. of binder)

Other curing agents can be used, but an adjustment to the curing agent ratio will have to be made.