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New Combustion
Posted: Tue Nov 22, 2005 9:34 pm
by Bluerift
I just built a new combustion. It has a 3 inch chamber that is a foot long and that goes out to a 1.5 inch barrel that is 5 feet long. I was wondering should I deacrease my barrel size? And is this a good setup? Hopefully I can post pictures soon
Posted: Wed Nov 23, 2005 2:19 am
by CS
3X12=36
1.5x60=90
36/90=.4:1
So that basically means that ya your barrel is way to big and/ or your chamber is to small. I dont know how to tell you wether or not you have a good setup because quite frankly I cant see any pictures. A little advice, take pictures and then post.
Incase you dont know a whole lot about CB ratios, 1:1 is a good ratio for first time spudders. Remeber yours was .4:1 so you need to either double you chamber size or chop your barrel in half so that you can shoot farther.
Posted: Wed Nov 23, 2005 12:00 pm
by boilingleadbath
...pimpmann22, you have had an offical brain lapse.
Ratios go by volume; thus:
3*3*12 = 108
1.5*1.5*60 = 135
Thus, the ratio .s .8:1
This is the optimum length for your barrel (or darn close). Don't shorten it, and don't make it longer - you'll only lose power.
see the <a href="
http://www.burntlatke.com/15cb.html">this</a> for details.
Posted: Thu Nov 24, 2005 2:52 pm
by CS
What was I thinking? Thank you for correcting me BLB.
Posted: Tue Nov 29, 2005 1:56 pm
by nodnarbisc
your both wrong. use pi*radius squared*hight to find th volume. the pipes arent 2 dementional pimpman and they arent square pipe either boilingleadbath.
Posted: Tue Nov 29, 2005 7:44 pm
by boilingleadbath
Yes, but the pi terms cancel out.
...unless you are using a square barrel/chamber. Which I don't recomend, because square is a vary poor shape for a pressure vessel... I forget the wording for the reason, but basical it's because you get a bending force, instead of a pure tension force... and materials can't take as much force like that.