SDR7 hdpe pipe

[Kevinfire]

Hello everyone. Been shooting fireworks for most of my life, and have a question for the more versatile members out there. I have an opportunity to get a bunch of SDR7 Hdpe pipe. I measured the I?d at 1.75?, Has anyone used this as mortars for Excalibur shells? I don?t presently have any to physically try them in the pipe to see how tight it will be.

[Okimarine]

I just measured another premium canister shell and the shell itself is under 1.75" but right at 1.75 with the fuze going down the lenght of the shell. I personally use the dr11 1.91". The sponsor on this site that I purchased from lists the dr9 at 1.81" and says "These tubes work well with smaller (less "premium") aerial shells". Sorry I can't give you a definate answer. Maybe someone else on the forum has first hand experience and can provide some good advice.

[joewad]

The answer basically lies in the thickness and material composition of the SDR7 walls compared to that of a dr11 gun. Let a search engine be your friend, sorry I don't know the specifics. What I have seen over the years here on this board is the discussion of other type of HDPE guns for canister mortar use does not "measure up" to the safety afforded by dr11. I'm also sure someone here will chime in with the knowledge given time.

[Kevinfire]

The SDR7 pipe wall is a lot thicker than the SDR9 or 11. The specs I found on line has it rated with a higher psi rating. I was just curious if anyone had tried this pipe or not. Thanks for the insight.

[Okimarine]

The SDR7 pipe wall is a lot thicker than the SDR9 or 11. The specs I found on line has it rated with a higher psi rating.

If I had them, I would try it for sure. As long as you don't have to beat the shell to the bottom of the tube, the snug fit could possibly get you alittle more height. If not with the Excalibur for sure with the cheaper 1.75" ball shells.

I built a mortar rack a few years ago with used Excal tubes. Cut the bottoms off and plugged with wooden plugs off Pyroboom. The plugs fit easily in the 1.91" dr11 but had to heat the Excal tubes before I could beat them in. When I was finished you could tell the bottom of the tubes bulged out alittle. With that being said, I know the dr11 are larger in diameter than they have to be for Excalibur shells.

[pyroboom]

I'm guessing a 2" IPS DR7 won't work. I don't know of anyone that has ever shot from a 2" DR7 tube, but I'd be interested to know what you find out. The specs of a DR7 should be all over the internet. I use use calipers and measure the OD of the shell and include the fuse.

[jamisonlm3]

Do you a way to find out the exact ID of your pipe? DR9 is already a fairly tight fit for some shells. If it has an even smaller ID, I think some shells might not fit or would be a very tight fit. You'd need soemthing to push the shell down to the bottom and to retrieve it in case it doesn't shoot. It may be some shells will fit and others won't, but you'll only find that out after you buy them. There's also the problem of plugging them.

[ssmith512]

DR7 ID is 1.66", on average, per manufacturers specs. I doubt a 1.75" canister shell with fuse will fit.....properly.

[Kevinfire]

I measured the id of the pipe with a tape measure and it was at 1.75”. I just got my Excalibur platinums yesterday and they measure under 1.75”. I will take my calipers and measure them more acutely, I am going to physically try the shell on the pipe tomorrow to see the “true” fit. The pipe is being given to me so I don’t want to pass up on all the free possible mortars. This is the first time I have had the Excalibur Platinum, maybe the are thinner because they are longer than the standard Excaliburs.

[Okimarine]

I am going to physically try the shell on the pipe tomorrow to see the ?true? fit.

Sweet, I'm looking forward to finding out if they fit.

[Kevinfire]

I forgot my calipers at home, but I did bring the shell with me. The Excalibur Platinum slides right into the pipe with the fuse. No pushing necessary to get it in either. Once I get a chance to fire one I will let you know how well it works. I am still going to put the calipers to it so I know the exact size.

[Okimarine]

Thats great news. Now you can start cutting to length, plugging the bottoms and building some racks. You may find later that some shells fit tighter and have to assist them to the bottom as jamisonlm3 said but as long as your plugs are secured well it shouldn't be a problem. The only time I've had issues with a plug was a fiberglass tube I reused. The concrete like substance in the bottom broke up in one after a couple years of use. Never an issue with wood plugs and hdpe. Not sure if they have any in stock but I've purchased alot of tubes and plugs off pyroboom. Pretty quick service. Just make sure you get a accurate I.D. measurement because they sell 1.81" and 1.91" plugs.

[ssmith512]

Wow, I am surprised they fit. Good that they do, as free is always nice right?! :-)

[Kevinfire]

How thick does everyone make their plugs? I have my tubes that come with Excalibur plugged about 3/4” and they are attached with screws and glue. I may have to get another hole saw to cut the plugs for my “new” tubes.

[jamisonlm3]

I make my plugs from scraps of 2x boards, usually scraps of 2x4. Cut them down to around 1ft or shorter pieces and drill them with a drill press. To make things easier, make sure the next cut of the hole saw overlaps slightly where the last plug was cut. This helps keep the hole saw cutting. You might have to get a couple of hole saws until you find one that makes plugs that aren't too big or small. The plugs for DR11 mortars can be made with a 2-1/8" hole saw. The plug is actually slightly too big and needs to be hammered in, but the HDPE stretches just fine.

[Kevinfire]

Put the calipers to the pipe and it is measuring 1-11/16 (1.688). The Excalibur Platinum has a whisper a room around the shell.

[jamisonlm3]

Just out of curiousity, what's the diameter of one of the excal platinum shells? A couple of years ago, I used my pair of calipers to measure several shells I had. A regular excal was 1.654. Black Cat's Diablo was 1.590". Brother's Quest was 1.675". None of these measurements included the fuse.

[Kevinfire]

The shell by alone measures just a hair over 1-5/8, with the fuse is just a hair under 1-3/4.

[PYRODAN]

5816

This might help.....