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Ranges of other people's Advanced Combustions

Posted: Sun Dec 07, 2008 1:04 pm
by spudkilla224
hello, i'm building an advanced combustion and i want to get a rough estimate about the range of how far an Advanced Combustion Cannon shoots with "PROPANE" as a fuel.

thank you

Posted: Sun Dec 07, 2008 1:17 pm
by jrrdw
From what I've read around here, it's going to average around 250/300 yards.

Posted: Sun Dec 07, 2008 2:40 pm
by Sticky_Tape
Well it depends. Replys will differ if you don't give specs.
ex: it will go 100000000 yards!!!!!1!!!1!
ex2: If the flames are hot enough will you have a baked potato?
ex3: give specs

Posted: Sun Dec 07, 2008 3:57 pm
by spudkilla224
my chamber is going to be 32" Long, and the barrel is going to be 7' long. so would anyone know how far it should shoot?

Posted: Sun Dec 07, 2008 4:21 pm
by jook13
What size of barrell (diameter)? What are you planning to use as "ammo"?

If you are shooting potatoes expect a range of around 2-300 yards tops.
If you are shooting golfballs and induce a good backspin then close (not quite though) to double that.

In my golf ball combustion It shoots till you cant really see the ball land. I put a screw at the end of the barrel through the top sticking in about 1/8 an inch. when the golf ball passes by it catches the tip of the screw and causes some intense backspin.

Posted: Sun Dec 07, 2008 5:55 pm
by spudkilla224
1.5" For potato's and wooden slugs, and a 2" sleeved SCH.40 Golfball Barrel.

Posted: Sun Dec 07, 2008 6:34 pm
by jimmy101
jrrdw wrote:From what I've read around here, it's going to average around 250/300 yards.
I think that is pretty darn optimistic.

Like others have said, without knowing the ammo and gun spec there is no way to predict the range.

Spuds don't carry very well. Tennis balls are even worse. Golfballs carry very well. The difference caused by different ammo are huge, probably as much as a factor of two or more in maximum range.

Big gun or little gun? "Little" - fired from the shoulder or hip. "Big" - fired from a mount, perhaps with extra support for a long barrel. Again, the specs will make a huge difference in the performance.
my chamber is going to be 32" Long, and the barrel is going to be 7' long. so would anyone know how far it should shoot?
Very rough guess for a 2" half-spud ammo, 1:1 CB ratio, figure ~100 FPS per foot of barrel length. So, your muzzle velocity will be in the vicinity of 700 FPS.

Get HGDT and model your gun. It'll give a pretty good idea ot the muzzle velocity. Fiddle with the ballistics calculator to estimate the range with various ammos.

Posted: Sun Dec 07, 2008 6:36 pm
by starman
For potatos, you're going to be limited to the 250 yrd range no matter how long your barrel and powerful your cannon overall....just too much drag and flight inconsistancy.

With my burst disk setup on my thunder cannons, I can launch a golfball easily 500 yds. I lose sight of it at approximately the 300yrd mark and it's still on a fairly straight flight at that point. Distances in the 1/2 mile range wouldn't surprise me actually. Barrel quality and length does make a big difference in this case.

Posted: Sun Dec 07, 2008 7:05 pm
by jrrdw
jrrdw wrote:
From what I've read around here, it's going to average around 250/300 yards.
I think that is pretty darn optimistic
What can I say, I'm a optimistic kinda guy! :D

Generally speaking, it's a average estimate for the average spud gun.

Posted: Mon Dec 08, 2008 10:35 am
by Radiation
starman wrote:For potatos, you're going to be limited to the 250 yrd range no matter how long your barrel and powerful your cannon overall....just too much drag and flight inconsistancy.
Not to mention that power beyond what you'd get from 250-300 yards cause your potato to break up in the barrel. I made a few improvements to my large spud gun and I was very disappointed to find out it caused my potatoes to do just that. :(

Posted: Mon Dec 08, 2008 12:15 pm
by starman
Radiation wrote:
starman wrote:For potatos, you're going to be limited to the 250 yrd range no matter how long your barrel and powerful your cannon overall....just too much drag and flight inconsistancy.
Not to mention that power beyond what you'd get from 250-300 yards cause your potato to break up in the barrel. I made a few improvements to my large spud gun and I was very disappointed to find out it caused my potatoes to do just that. :(
Yep, long barrels and low to modest energy chambers are your best bet to extract to best possible performance for a potato. High energy chambers, fast valves, burst disks, etc are sure ways to make potato salad in the barrel.

Posted: Mon Dec 08, 2008 5:44 pm
by spudkilla224
What's and example of a high-engery chamber? is it a chamber that is large in overall size?

Posted: Mon Dec 08, 2008 6:02 pm
by starman
spudkilla224 wrote:What's and example of a high-engery chamber? is it a chamber that is large in overall size?
Medium to large chambers with properly metered, well mixed fueling in the combustion world. Any hybrid setup would fit this description as well. And large chamber and lots of PSI in the pneumatic world.

Posted: Wed Dec 10, 2008 9:20 pm
by Xxplosive42o
High Energy:

Posted: Wed Dec 10, 2008 9:56 pm
by starman
Xxplosive42o wrote:High Energy:
Relatively speaking, yes. Those "Thebug" videos have made the rounds several times in the forum.