Double loading shells

[PyroAce]

When you double load a mortar, that is to say rip the quickmatch off of one shell push it in the mortar and put another shell on top, is this a safe practice? The only thing I can think of going wrong would be the lift going off and possibly damaging the shell beneath it? But even then I don't think the lift going off would damage a well pasted shell?

 

Just thought I'd ask to see if any risks are involved.

[dagabu]

The times we have double bubbled a shell, we pull the lift cup off too, the pressure from a second shells lift cup could blow out the mortar.

 

-dag

[nater]

For shells of the same size, I have pulled the lift cup off and dumped part of the lift into the mortar to account for the extra weight. Essentially making a peanut shell. If I am piggybaking a 2 onto a 4 for example, I pull the lift cup and save the lift from the smaller shell for something else.

 

With that said, you need to be careful that you don't create too much pressure and blow up the mortar. Experiments I have seen first hand vary with the number of shells a mortar will hold.

[Hoppy]

We have double bubbled shells while experimenting...come to think of it we successfully lifted 4 shells (quadruple bubbled?) out of a single mortar when we forgot to grab a rack to shoot mulitiples - saftey was always first, and more than 4 wasn't an option with a regular size HDPE mortar.

 

Highly effective? Yes, if done properly

Efficient? Sure, if setup space or materials were minimal

Recommended? Depends. This was purely for experimenting from a safe distance while keeping a bunch of pyro's happy. Not recommended for a home show/small backyard setup, err, any show for that matter as it's best to just build racks or take all of those thickwalled cardboard tubes and use liquidnails...that being said, I know many on here have double bubbled before to get a few extra shells up in the air with what they had, especially in their finale racks and they were all successful.

 

P.S - Always put cans on the bottom...just my $.02

[PyroAce]

Thank you for the replies!

 

So there's even a name for it "double bubbled", I like it!

 

So the issue is more of whether the mortar can handle the lift charges going off rather than the shell underneath being damaged or destroyed?

Is this double bubbled technique widespread or do a lot of pyros avoid doing it? I've seen a couple of videos where a whole rack was setup this way, but the shells I think were around the 2" variety so shell size must play a factor. In the video the lift cup is left on, quickmatch is completely removed, the hole in the lift cup where the quickmatch was pulled out is left as is, the gases from the shell above have no problems getting in and igniting the lift charge, I personally would rather put a piece of bare blackmatch sticking out just to ensure it goes off.

[nater]

In the display industry it is more common to drop unlifted small shells to ride up with larger ones, much like rising effectss than to drop two shells of the same size on each other. But none of these ideas are widespread. From a safety standpoint, it is best to plan a show to have a mortar for every single shell.

 

And as I have said before, there are no worries about anything in the mortar not lighting. There is about a 15 ft tall flame that shoots out of the mortar before the shells even budge.

[dagabu]

Thank you for the replies!

 

So there's even a name for it "double bubbled", I like it!

 

So the issue is more of whether the mortar can handle the lift charges going off rather than the shell underneath being damaged or destroyed?

Is this double bubbled technique widespread or do a lot of pyros avoid doing it? I've seen a couple of videos where a whole rack was setup this way, but the shells I think were around the 2" variety so shell size must play a factor. In the video the lift cup is left on, quickmatch is completely removed, the hole in the lift cup where the quickmatch was pulled out is left as is, the gases from the shell above have no problems getting in and igniting the lift charge, I personally would rather put a piece of bare blackmatch sticking out just to ensure it goes off.

 

Officially, no. Double bubbling is not in any way approved as a safe way to launch shells. That said, I cant think of any group that has not dropped in a shell that has lost its lift cut and instead has decided to check it back into the magazine to be counted as an incomplete shell...

 

-dag

[cogbarry]

In my state, steel guns are required for peanut shells because of the higher pressure.

 

In practice, I have dropped a shell of same size into a mortar with an existing failed shell. In most cases, both shells are fired from the mortar. The lift from the top shell lights the previously failed lift of the bottom. This is done in an attempt to fire a failed shell and I haven't seen this done for normal shooting. In my neck of the woods, it's known as "piggy backing" and is not practised routinely. It is not considered a safe and is considered a big "no no" if the bottom shell is a salute.

[dagabu]

In my state, steel guns are required for peanut shells because of the higher pressure.

 

In practice, I have dropped a shell of same size into a mortar with an existing failed shell. In most cases, both shells are fired from the mortar. The lift from the top shell lights the previously failed lift of the bottom. This is done in an attempt to fire a failed shell and I haven't seen this done for normal shooting. In my neck of the woods, it's known as "piggy backing" and is not practised routinely. It is not considered a safe and is considered a big "no no" if the bottom shell is a salute.

 

I cannot confirm or deny that I have seen this done in the past...

 

-dag

[cogbarry]

I cannot confirm or deny that I have seen this done in the past...

 

-dag

 

LOL!