8ft Coaxial Shoulder Launched Golfball Cannon.

[deathbyDWV]

If it can take the recoil... I've always wanted to shoot a trailer hitch ball... Those are 2 inch(my barrel size) but you could use a 1.5 inch hitch with wadding...

[Mtrhd0024]

If it can take the recoil... I've always wanted to shoot a trailer hitch ball... Those are 2 inch(my barrel size) but you could use a 1.5 inch hitch with wadding...

You shouldn't.... Have even mentioned that.

Muwahaha the carnage I'm envisioning with that idea stuck in my head.

[c11man]

This is a grear first piston valved cannon man.
now im not gonna nag you about the endcap but sadly the ther fittings on the cannon are dwv aswell. i know from experience that a local home improvement store (menards or similar) do not carry any pressure rated fittings in 4" pvc. i know they are coupler and reducer bushings but they are still dwv. even if you dont believe me please go read on the fittings to see if it reads NSF-DWV. of course finding that would be bad. i accidntly used some dwv on my 4in cannn and it failed (no shrapnel thankfully) and just dont want any injuries.

[deathbyDWV]

Yep, I can tell now that the socket depth is too short. I didn't see that earlier...

i know from experience that a local home improvement store (menards or similar) do not carry any pressure rated fittings in 4" pvc

Actually, my home depot stocked pressure rated fittings for a while once...
I always get my stuff at locke supply.

[Mtrhd0024]

This is a grear first piston valved cannon man.
now im not gonna nag you about the endcap but sadly the ther fittings on the cannon are dwv aswell. i know from experience that a local home improvement store (menards or similar) do not carry any pressure rated fittings in 4" pvc. i know they are coupler and reducer bushings but they are still dwv. even if you dont believe me please go read on the fittings to see if it reads NSF-DWV. of course finding that would be bad. i accidntly used some dwv on my 4in cannn and it failed (no shrapnel thankfully) and just dont want any injuries.

All of the fittings were purchased from a specialty pipe store which sells nothing but PVC, and everything but the cleanout cap is pressure rated... In fact I accidentally started to purchase a DWV fitting, and the lady at the counter asked if I needed pressure rated fittings or not, and then made me go back and get a different fitting.

I've also purchased a DWV coupler from Home Depot that I was originally going to use to sleeve the 4" pipe in order to tap in the pop off valve and the gauge. (Because it was way cheaper, and I figured DWV would be ok since I was just sleeving the 4" pipe to tap a hole!) In the end, I just decided to play it safe and not use it, and to go ahead and tap them into the pre-existing couplers. The difference between those DWV couplers and the couplers i used are substantial. The plastic is about 2x as thick, and the socket depth is a whole lot deeper!

So I'm pretty sure I'm good to go, but I'll check one more time tomorrow just to make you guys happy! :thumbright:

[MrCrowley]

I recommended you get rid of the clean out cap but you've been told enough and you've made your mind up. Personally I think one day it'll fly off, I guess if you shoulder the cannon it wont be so bad, just don't stand behind it.

As for range with golfballs, you'll find they will max out at around 500-600m. I don't recall anyone having a definite number but using compressed air and firing from a piston valved cannon you can only shoot them so far. I think even the SWAT (look it up) cannon wouldn't throw them further than 600m or so and I believe that had a 20-30' barrel if I remember correctly.

But anyway, nice build. You will learn soon enough that it's not worth taking the risk with DWV fittings, even if you make them strong, you've already drilled two holes in the back of that fitting. Certainly doesn't help.

[Mtrhd0024]

I recommended you get rid of the clean out cap but you've been told enough and you've made your mind up. Personally I think one day it'll fly off, I guess if you shoulder the cannon it wont be so bad, just don't stand behind it.

As for range with golfballs, you'll find they will max out at around 500-600m. I don't recall anyone having a definite number but using compressed air and firing from a piston valved cannon you can only shoot them so far. I think even the SWAT (look it up) cannon wouldn't throw them further than 600m or so and I believe that had a 20-30' barrel if I remember correctly.

But anyway, nice build. You will learn soon enough that it's not worth taking the risk with DWV fittings, even if you make them strong, you've already drilled two holes in the back of that fitting. Certainly doesn't help.

Cool thanks for the info!

And yea, I have no desire to play chicken with DWV fittings, but considering that cap is reinforced with other PVC fittings, and then filled with epoxy (so its basically like a solid plastic cap now) i should be ok. And yea, I'm not standing behind it, so if it does let go, I should be ok. But I'll keep an eye on it, and if there are any signs of fatigue, (i.e. a crack) then it'll be retired in favor of a better solution!

I've taken this cannon up to its max pressure i believe 3 times now. Normally I just take it up to about 80 PSI, because thats how high it will go on one filling of my air compressor. Its still insane even at 80, and unless I'm going for distance or damage, the pressure stays between 40 and 80, with the majority of shots being done at about 40.