Zephyr on a Aerotech 29mm? Extra BP needed?

[overklock]

Anyone have any experience launching a Zephyr on an Aerotech 29mm? Specifically a G-76, or even a Cesaroni 29mm H motor? I'm having a difficult time finding the ejection grain amount that's included with the motors. Suppose I could manually weigh it, but don't want to risk losing powder.

Ground testing isn't really an option where I am (and is pretty difficult with single stage anyway). Emailed Apogee and they said extra ejection charge powder shouldn't be needed, but that's quite the risk with the amount of work I've put into this thing.

Anyone have any experience with this?

 

[tfish]

hopefully sometthing below will help...

https://www.rocketryforum.com/threads/at-single-use-ejection-charge-amount.176427/
https://www.rocketryforum.com/threads/aerotech-dms-bp-delay-charge.136069/
https://www.rocketryforum.com/threads/mpr-hpr-reloadable-motor-bp-ejection-charge-masses.68188/
https://www.google.com/search?q=aer...jMuNC4xmAEAoAEBwAEB&sclient=gws-wiz-serp#ip=1
Tony

 

[waltr]

The G76G for the 29/40-120 hobby-line case comes with 0.7gram BP ejection charge.

This is very marginal for a 4" diameter BT. I've had it work and also fail in a 4" LOC Goblin.
I have tried adding more BP but can only get about 1.1grams in a 29/40-120 case's charge well.
I now only use RMS 29 cases and reloads which come with 1.4gram BP ejection.

 

[TheTank]

Anyone have any experience launching a Zephyr on an Aerotech 29mm? Specifically a G-76, or even a Cesaroni 29mm H motor? I'm having a difficult time finding the ejection grain amount that's included with the motors. Suppose I could manually weigh it, but don't want to risk losing powder.

Ground testing isn't really an option where I am (and is pretty difficult with single stage anyway). Emailed Apogee and they said extra ejection charge powder shouldn't be needed, but that's quite the risk with the amount of work I've put into this thing.

Anyone have any experience with this?

I flew my original Zephyr of the G76G RMS motor as well as the G79W LMS motor and ejected fine (but I made sure I had a great NC fit). I was very “green” at the time and when I reached out to Apogee to ask them same question, Tim responded with “it should be fine.” If you have a good seal and your NC isnt a sloppy fit, you should be in the same boat. If you can, add a little BP to the red cap to increase the charge a bit - it should be able to take a little more.

 

[jmasterj]

You can extend the charge well with tape, that's worked fine for me.