Possibly stupid ejection charge testing question

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smoon

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I have a Wildman Warrior mini that I bought the dual deploy upgrade for and have everything ready to ground test.

The calculators tell me .15g of black powder for my apogee ejection charge. Secured inside the charge well, taped up, etc. inside the rocket, how loud will this be when it goes off?

I live in a townhouse community and don't want my neighbors on my case or the cops showing up, wondering if I am some kind of undesirable discharging one of my many firearms inside the city limits (or worse).

Thanks for any insight on my total newb question.

Steve
 
Do your ground tests outside of city limits and away from any occupied structures, and find out safely.
 
A lot of the noise has to do with the way the powder is confined AND the size of the charge. At one of our recent launches a fliers charges could be clearly heard going off at nearly 5000', sounded about like a high powered pellet rifle. As somebody else said its probably a good idea to get out of your townhouse community and do your testing.
 
If worried about neighbors then ground test at your launch site.

Just make sure and notify the RSO and LCO so they don't hear certain noises from areas they shouldn't be hearing them. They will most likely point you to a area where it would be safer to do so.
 
I have a Wildman Warrior mini that I bought the dual deploy upgrade for and have everything ready to ground test.

The calculators tell me .15g of black powder for my apogee ejection charge. Secured inside the charge well, taped up, etc. inside the rocket, how loud will this be when it goes off?

I live in a townhouse community and don't want my neighbors on my case or the cops showing up, wondering if I am some kind of undesirable discharging one of my many firearms inside the city limits (or worse).

Thanks for any insight on my total newb question.

Steve

That small ejection charge won't be loud at all. That said, I don't think I would do it around the townhouse community to avoid attention. If you have a friend who lives in a single family home, I wouldn't worry one bit about setting it off in the back yard of my home.

Honestly, I think you will get more of a thump than anything. And not overly loud.

Heck, this weekend would be perfect around here. It would be a fraction as loud as most of the illegal fireworks being shot in our neighborhood.

--Lance.
 
Thanks for the insight and advice.

Good point Lace. Nobody would think twice tomorrow night about a loud noise. Heck, last year there were people launching mortars in our street, and I was afraid for the safety of my home. I called the sheriff and explained exactly what was happening. They said to call back if one landed on my house. Otherwise, let them have their fun. I hope that is not their attitude when someone is trying to break into my house.

I thought about doing at our next launch. I will e-mail the president of our club and ask him what he thinks.

Steve
 
I simply emailed my neighbors in my townhome neighborhood and let them know what I was doing and why. The only difficulty I had was someone asking to avoid the time they put their little one down for a nap.
 
Thanks for the insight and advice.

Good point Lace. Nobody would think twice tomorrow night about a loud noise. Heck, last year there were people launching mortars in our street, and I was afraid for the safety of my home. I called the sheriff and explained exactly what was happening. They said to call back if one landed on my house. Otherwise, let them have their fun. I hope that is not their attitude when someone is trying to break into my house.

I thought about doing at our next launch. I will e-mail the president of our club and ask him what he thinks.

Steve

Not sure how your "sheriff" is, but in our county, they pretty much let the fireworks go on the 4th. If you shoot any off on the 3rd or the 5th, you can expect the sheriff an your @$$. It's a one day a year grace period they give you. Of course if you do something stupid like drop one on someones house, they will take notice if it's the 4th or not. I suspect your sheriff is operating pretty much the same way. They have to get re-elected after all.
 
Not sure how your "sheriff" is, but in our county, they pretty much let the fireworks go on the 4th. If you shoot any off on the 3rd or the 5th, you can expect the sheriff an your @$$. It's a one day a year grace period they give you. Of course if you do something stupid like drop one on someones house, they will take notice if it's the 4th or not. I suspect your sheriff is operating pretty much the same way. They have to get re-elected after all.

They simply don't have the time or resources to go after people setting off fireworks on the 4th. I'm sure they prioritize the calls and on a day like the 4th people setting off illegal fireworks is at the bottom of the list. As long as they aren't being complete morons and are reasonably safe they will get a pass. And around here they can do it a week before or a week after and nothing happens.

And last week I tested a few old ejection charges in the backyard. I had made these with Pyrodex a year ago and never used after I switched to black powder. I set up my old Estes Phoenix with the ejection charge in a used D12 case. I stood off to the side of the rocket and put on safety glasses. The first few didn't work; which is what I expected as most of them were from the reject pile. I cleaned off the battery terminals with a little sandpaper and set up the next one to test. I touched the wires to the battery. Nothing. I rubbed the wires a little harder against the terminals and KABOOM. The nose cone was untethered and shot 30 feet into the back yard. I quickly put everything away and hoped nobody called the cops. That sucker was LOUD. I tested two more the next day and they were closer to the thump llickteig1 talked about. That has been my experience in the past too, so I was really surprised at all the noise the one made.
 
0.15g seems really small. like... 1/4 of the size of a 24mm ejection charge. Are you sure that's right? It may be, if the chute compartment is real tiny... just... REALLY small.

Good call on alerting the neighbors--and yes, if I was trying to put a little one down, I'd not want some yahoo blowing stuff up in a townhouse area...


Later!

--Coop
 
I agree with Coop- that is a really small charge. The Mini's are 38mm diameter, right? They are fiberglass. Are you using friction fit or sheer pins? I would probably at least double it, and possible triple it.
 
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