This article is from the Model Rockets FAQ, by Wolfram von Kiparski with numerous contributions by others.
Review: A High Power rocket is a model weighing more than 1500 grams (3.3 lb)
or containing more than 125 grams of propellant or containing any
motor with more than 62.5 grams of propellant.
When this question was posted to r.m.r a while back, these were the pre-
dominant suggestions and tips:
- Start with E/F/G kits with 29mm motor mounts from Estes/NCR, LOC or
Aerotech. These should be the easiest to build.
- Read and become familiar with the NAR and/or Tripoli High Power Safety
- Get familiar with and use expendable motors before jumping into
- Join a high power club if possible (local NAR section or Tripoli
- Be very careful of the construction differences between model and high
power rockets. You HAVE to build higher power rockets to be more sturdy
than model rockets (see the next question).
- If not already a member, join both the NAR and Tripoli (if you can
afford high power rocketry, you can afford to join and support both