CTI ejection charge

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qquake2k

Captain Low-N-Slow
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According to their website, CTI 54mm reloads' ejection charge is 2.0 grams of BP. If you require more, it says, "add additional powder on top of the cap and seal cavity with tape". Can anyone tell me how much room there is in the cavity for extra BP? Is there room for an extra gram or two? A photo would be good. I won't know how much I'll need until I do ground testing, but I'm curious. Unfortunately, I don't have the reload yet.
 
FYI, I'm not pushing out a nose cone, it's a coupler with a bulkhead in it.
 
Calculate the volume and use one of the tables on line or in a book to give you an approximation, then test and tune on the ground....and then once you are happy, deduct 2g and you will know what to add.....right?
 
This is a 38mm CTI. And there is easily enough room for another 1-1.5g level in the well. You could always remove white disk and get more space.

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I never thought about using an online calculator. I tried six different ones, and got four different results. The first gave me 2.2g for 5psi and 200lbs of bulkhead force. The only option was 5psi. The next gave me 3.8g for 10psi. The next gave me 3.5g. It was a chart with no psi listed. The last three all gave me 4.8g for 10psi.
 
I wonder if the 38mm and 54mm are the same. They do take different delay drills.

Yes the 38 and 54 BP wells are different. I have added powder to both for many years and things have worked out well for me. The 54mm motors is easier to add powder to than the 38mm motor. I always remove paper disk add powder than place disk back over powder and seal it off with masking tape. I added more powder to the CTI 54mm J360 skid which I flew in my LOC 7.5" Warlock and ejection worked very well. I just filled well to the top and sealed it with masking tape. The 38mm and 54mm delay adjustment tools are different.
 
Just make you a tape cup. No need to remove the CTI cap. Put as much BP in as you want.

Jim
I have always wondered if you just put extra on top of the cap does it get burned or just pushed out of the tube unburned? It doesn't take much time to remove the BP cap.
 
Jim
I have always wondered if you just put extra on top of the cap does it get burned or just pushed out of the tube unburned? It doesn't take much time to remove the BP cap.



CTI has always said you don't need to remove the cap. Everything burns instantly with 4f bp. I have done it both ways and noticed no difference.
 
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