RNWS Weight Cartridge: Purpose and Usage Explained
By High Power Model Rocketry | Published: 2026-10-30
Category: Tips & Care
Learn what an RNWS weight cartridge does, why it matters for rocket stability, and how to use it in your high-power rocket builds.
Quick answer
An RNWS weight cartridge lets you adjust nose weight in your high-power rocket to fine-tune stability without buying multiple nose cones.
Why adjust nose weight?
Nose weight moves the center of gravity forward, increasing stability in flight. Different motor sizes and launch conditions may require different amounts of weight to keep the rocket flying straight.
Trade-off: modularity vs. one-piece weight
A weight cartridge like the RNWS allows you to swap weights between flights, but it adds a few grams compared to a glued-in fixed weight. For most sport flyers, the convenience outweighs the small mass penalty.
Frequently Asked Questions
- What does RNWS stand for?
- RNWS stands for Rocket Nose Weight System. It is a modular cartridge that fits inside specific nose cones to add or remove weight as needed.
- How do I install the weight cartridge?
- Slide the cartridge into the nose cone base. Secure it with the included bulkheads and eye bolt. Make sure it is snug but not forced; you should be able to remove it for weight changes.
- Which nose cones work with the RNWS cartridge?
- The 5.5" cartridge fits both the 5.5" short and long cone systems. The 4" and 7.5" versions fit their respective cone diameters. Check your cone's inner diameter before ordering. Measure your nose cone inner diameter before purchasing to ensure compatibility.
- Can I use the cartridge with any motor?
- Yes, the cartridge itself is motor-agnostic. It simply adds weight. The amount of weight you need depends on the motor's thrust curve and your rocket's design. Start with the manufacturer's recommended weight and adjust from there.
Product facts
- RNWS Weight Cartridge: The 4" RNWS Weight Cartridge allows you to affordably make different weights for your motors of choice. You can customize your nose weight for each motor and flight condition without buying a new nose cone each time.
RNWS Weight Cartridge
