Aerotech floating front closure - newb question

[Buckeye]

I picked up 38 and 54 hardware specials from Wildman, and they have the floating forward closure. I never saw this before. Somebody please tell me this will work with any and all AT reloads that fit these cases, and that I don't need to buy a special kind of reload!

 

[Steve Shannon]

I picked up 38 and 54 hardware specials from Wildman, and they have the floating forward closure. I never saw this before. Somebody please tell me this will work with any and all AT reloads that fit these cases, and that I don't need to buy a special kind of reload!

These work with the all the loads that fit that case and with the additional spacers that one case handles loads that have one or two fewer grains. No special loads required.


Steve Shannon

 

[Buckeye]

These work with the all the loads that fit that case and with the additional spacers that one case handles loads that have one or two fewer grains. No special loads required.


Steve Shannon

Awesome. Thanks. This is what I expected, but I got nervous when I saw RMS Plus, RMS EZ, and other differntly named reloads.

 

[KenRico]

The stock floating closure will not work with long burns that required the extended forward closure, but AT did release recently a floating extended forward closure including a tapped one for 54mm that will work with the long burn reloads only.

Kenny

 

[Steve Shannon]

The stock floating closure will not work with long burns that required the extended forward closure, but AT did release recently a floating extended forward closure including a tapped one for 54mm that will work with the long burn reloads only.

Kenny

Thank you for correcting me. I didn't realize that and it is an important point.
Wouldn't the stock floating closure still work with electronic deployment? In other words, isn't that just because the long burn motors require a longer delay for motor deployment?


Steve Shannon

 

[KenRico]

Thank you for correcting me. I didn't realize that and it is an important point.
Wouldn't the stock floating closure still work with electronic deployment? In other words, isn't that just because the long burn motors require a longer delay for motor deployment?


Steve Shannon

I don't believe so because most of the long burns are 'plugged' .. what is shipped is not a delay but a smoke cartridge .

Kenny

 

[Steve Shannon]

Can the motor be assembled without the longer forward closure, either by shortening the smoke grain or by using a delay grain that fits the regular length floating forward closure?

What I'm getting at is, is there any reason a person couldn't make do with the standard floating forward closure other than the delay/smoke grain length?


Steve Shannon

 

[tbonerocketeer]

Can the motor be assembled without the longer forward closure, either by shortening the smoke grain or by using a delay grain that fits the regular length floating forward closure?

What I'm getting at is, is there any reason a person couldn't make do with the standard floating forward closure other than the delay/smoke grain length?


Steve Shannon

You could shorten it. The only concern is the amount of material being enough to keep the closure sealed for the entire motor burn.

 

[mikec]

I don't believe so because most of the long burns are 'plugged'...

Actually, most of the AT 54mm long-burns (e.g., J90, J135, J180, K185) have delays, exceptions being the K270 and the K375. I haven't found the delays to be very accurate, but they are still available.

As Chris says, I wouldn't try to shorten a delay grain for fear the closure would burn through. Some people have used a non-flammable plug in place of the delay grain, which I guess would be OK under research rules.

 

[Reinhard]

From a quick guestimate, based on the numbers in in the Aerotech Delay Reference Table it appears that a J135 burns about 0.876" of delay element length during the motor burn. This is longer than the longest non-longburn delay and only slightly shorter than the 0,95" of the available delay cavity length in a normal 54mm casing. There is a minimum delay thickness that has to remain while the motor is under pressure, or the delay will fail mechanically.

Reinhard

 

[Steve Shannon]

Thanks everyone. That's what I needed to understand.