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Does the AT 38 Special work?

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exprditer789

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I have not but i would like too.Soon as my dealer by me gets them in.:D
 

MattieShoes

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Is there any word on what vendors will be getting them, or when we should expect them to go on sale?
 

NAR29996

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I got one last weekend, but my vendor "cheated". He sold it to me with a Dr Rocket casing. I didn't get a chance to use it as it was too windy. Maybe at the April launch.
 

Kira_Majeric

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I have one of these, but will not know if it works until after XPRS in September. I will post what I think after that.
 

C.O.B.H.C.

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WILDMANRS

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I have used the spacer system and have them in stock, but the 38/360 case,spacer system i do not have yet (waiting for AT)
They work, the first time you use them its a little confusing, but after you have seen it done its no harder than any other AT reload.
If you have any questions about them feel free to give me a call .
Tim
Wildman Hobbies
815-638-3200
 

Hangar 11

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My second shipment of 38 Specials is due in this wed / Thursday.
Most are sold but I have a few left. They will not last long... order now...... www.hangar11.com

Also bumped up the deal for those looking to L2. [ I bundled the 38 Special with a complete 38/720 motor ] But you have to Join / login to my website to see the L2 special option pricing.....

Bobby B
www.hangar11.com

PS These are NEW FACTORY SEALED AEROTECH 38 Specials for 59.99 + shipping.
 

Estimado

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Does anyone know if the spacers and floating forward closure could be used in a 38mm/720 case in order to use it for some J reloads?
 

traveler

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Does anyone know if the spacers and floating forward closure could be used in a 38mm/720 case in order to use it for some J reloads?

I was just thinking the same thing: Could the spacers be used in a case larger than the 360? A 1080 maybe?


:cool:
 

bobkrech

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AT and CTI spacers are 1 grain long. You can use up to spacers 2 in a casings.

You can make a 2 grain casing into a 1 grain casing, a 3 grain casing into a 2 or 1 grain casing, a 4 grain casing into a 3 or 2 grain casing, a 5 grain casing into a 4 or 3 grain casing, a 6 grain casing into a 5 or 4 grain casing and a 7 grain casing into a 6 or 5 grain casing.

Bob
 

MattieShoes

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By the way, my dad certified L1 using a 38-special this past weekend. (H123W, a 38/240 load, with one spacer). They work fine. The only gotcha is the ejection charge... If you're using one spacer, the cannister where the BP goes is recessed into the casing but reachable without much trouble. I think with two spacers, you'd have to alter the build order of the motor to get the BP in -- put in the BP and cover with the sticker before inserting the aft assembly into the casing.
 

MattieShoes

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I was just thinking the same thing: Could the spacers be used in a case larger than the 360? A 1080 maybe?


:cool:
Each grain in the 38mm line is 120 Newton seconds, right? Are there AT 38/960 loads? 38/840? I was under the impression they jumped from 720 to 1080, in which case the two spacers wouldn't be enough...

So, I think this is the possible loadouts...
1320 -> 1320, 1080
1080 -> 1080
720 -> 720, 600, 480
600 -> 600, 480, 360
480 -> 480, 360, 240
360 -> 360, 240, 120
240 -> 240, 120
120 -> 120

So to cover the entire range, you'd want a 360, 720, and 1320 casing, 2 spacers, aft closure, forward seal disk (comes with the 38/720 casing), standard forward closure (for ejection charges), and sealed forward closure (warp 9's etc), and then you'd be able to use any 38mm reload AT makes I think...
 
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Handeman

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Each grain in the 38mm line is 120 Newton seconds, right? Are there AT 38/960 loads? 38/840? I was under the impression they jumped from 720 to 1080, in which case the two spacers wouldn't be enough...

So, I think this is the possible loadouts...
1320 -> 1320, 1080
1080 -> 1080
720 -> 720, 600, 480
600 -> 600, 480, 360
480 -> 480, 360, 240
360 -> 360, 240, 120
240 -> 240, 120
120 -> 120

So to cover the entire range, you'd want a 360, 720, and 1320 casing, 2 spacers, aft closure, forward seal disk (comes with the 38/720 casing), standard forward closure (for ejection charges), and sealed forward closure (warp 9's etc), and then you'd be able to use any 38mm reload AT makes I think...
Other then not needing the plugged forward closure for the Warp 9 loads, you are right. Here's the link to the Aerotech page with all the motor drawings that show grains etc. http://www.aerotech-rocketry.com/resources.aspx?id=6
 

Kira_Majeric

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Did you guys see that they just approved the spacers for 29mm and 54mm?
 

MattieShoes

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Other then not needing the plugged forward closure for the Warp 9 loads, you are right. Here's the link to the Aerotech page with all the motor drawings that show grains etc. http://www.aerotech-rocketry.com/resources.aspx?id=6
Hmm okay. I thought all the plugged required a plugged forward closure. My mistake. :)

Incidentally, AT recommends no more than 2 spacers, but they do say there's no technical reason why more can't be used. So in theory, it'd be possible to buy a 1080 case and use three spacers for the 720 loads.
 

Handeman

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Hmm okay. I thought all the plugged required a plugged forward closure. My mistake. :)

Incidentally, AT recommends no more than 2 spacers, but they do say there's no technical reason why more can't be used. So in theory, it'd be possible to buy a 1080 case and use three spacers for the 720 loads.
Other then the fact you have a much heavier motor then one with just a 720 case, yes. I don't think the spacers make a whole lot of difference in the larger motors, but they could have some affect with the smaller 29mm.

Only the end burning Warp 9 require the special forward closure. The bates grains, H999, I1299, etc come with delay grains so you can use a regular forward closure. The delay grains won't burn through because they don't light or get snuffed out at burnout.
 
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bobkrech

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Hmm okay. I thought all the plugged required a plugged forward closure. My mistake. :)

Incidentally, AT recommends no more than 2 spacers, but they do say there's no technical reason why more can't be used. So in theory, it'd be possible to buy a 1080 case and use three spacers for the 720 loads.
I believe TRA TMT and NAR S&T are not going to allow using more than 2 spacers for safety reasons. Motors with spacers are both longer and heavier than a shorter casing without spacers. These reduces the thrust to weight ratio of the motor and and can reduce the stability of the rocket by adding additional weight at the aft end of the rocket.

Bob
 

BsSmith

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1320 -> 1320, 1080
1080 -> 1080
720 -> 720, 600, 480
600 -> 600, 480, 360
480 -> 480, 360, 240
360 -> 360, 240, 120
240 -> 240, 120
120 -> 120
I don't think the spacers will work in the 1320 case because the grains in that case are longer than all of the other 38mm grains. Looking at the casing itself, it seems like it would hold 10 of the regular 38mm grains.

If the casing can be used, you'd need 2 spacers to get to the 1820 impulse.
 
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