SpudFiles

1 1/2 is better to use then a 2 inch barrel this is not my opinion this is a fact. Using a 2inch barrel you lose a lot of power plus most potato's don't fit in a 2inch barrel (at least the ones i have) 1 1/2 inch barrels are better also because they don't loose power like a 2 inch barrel and they fit golf balls perfectly. If you still don't believe that 1 1/2 barrels are better than 2 inch make your barrel interchangeable. Because you will soon discover that 2 inch barrels suck and that 1 1/2 inch barrel works a lot better.(if you don't make your gun barrel interchangeable you will soon be pissed off because you have to make a whole knew gun with a 1 1/2 barrel)
BARREL SIZES
Bigger than a 2 inch=
2 inch=
1 1/2 inch=

1 1/2 inch barrels are awesome

I will agree that I rather have a 1.5" barrel than a 2" barrel, but I dunno what kind of golfballs you have but around here they are no where near fitting in a 1.5" barrel.

i will agree with you also that 1 1/2 is way better than a 2 inch barrel golf balls fit in my barrel perfectly as long as they are still in some what new condition cause if there old they are all lop sided and wont fit. also if any one is building a gun for the first time make the barrel detachable because if you dont it really sucks because you have to make a whole new gun there is formulas you should use when building i think the volume of the combustion chamber should be 1 1/2 volume of the barrel dont take my word though research it. Your guns will be alot better if you first do a little bit of research before building cause trust me it will turn out a lot better if you research the next gun i plan on building is a "strafer" which is a automatic bb gun if you havent checked it out i would suggest to
1 1/2
2
and yes golf balls fit perfectly in my barrel (need more golf balls)

It is not a fact that they will give you better proformance, and there are tons of reasons to use a 2" barrel. That is like me saying 1/2" barrels are better than anything, coz they work better, and fit a AA battery so nicely. It really depends soley on the aplication.

i think both are good! you can shoot golf balls out of the 1.5" barrel and huge potatoes with the 2" barrell i happen to like the 1.5" better but its ur opinion. theres not really a huge difference!=)

how the hell are you getting golf balls in 1.5" pvc? i need to use SDR-21 to get them to fit, am i missing something here?

spudshot wrote:how the hell are you getting golf balls in 1.5" pvc? i need to use SDR-21 to get them to fit, am i missing something here?

I have seen cheaper, non-regulation golf-balls that will fit in sch 40 1.5" You have to shove them down, and the can get a bit tight, but they do work

Hey Its all relative, its to do with chamber size, barrel length and projectile, besides 2.5 inch barrels are ok you can fire tennis balls and nice large potatos

Eh, the old word "power". What does that mean, quantitativly?
Thougts on the answer to that question...

V: Speed, and speed alone... obviously not the answer. The 1.5" barrel would probably beat the 2" simply because you can put lighter ammo in it.
VM: Momentum. You want heavy projectiles to maximize this, that sugests a large barrel.
VVM: Energy is a possibilty. This probably depends on the target; I suspect maximizing energy (transfer) helps mostly with penetrating. (plywood, car doors...) There is no 'power' difference between the barrel sizes, if you put the same projectile mass in them. Heavier projectiles are better (less loss to the propellent gas) and are thus prefered - large barrel diameters facilitate this.
VVVM: "power", as I like to call it. Basicaly the rate of energy transfer during a collision (non-yeilding target assumed) (get it? VVM [energy] per time [third V]) Probably the best measure for cracking things, (computer monitors, bricks, concrete bridge supports) and bursting water containers. (milk jugs, soda cans, maybe mellons) Playing with the GGDT indicates that this is a fairly low mass (40-80 g, depending on pressure, for my air cannon). A smaller diameter barrel may be helpful to fulfil this goal.

Remember; this basicaly only applies to a combustion. In almost any pnematic, (if you have the valve to support it) a fatter barrel is better: you'r limmeted not by the amount of propellent gas you have, but by the length of your barrel.

I've got 100m with my 2"combustion with only a 3" by 12" long chamber using a potato.
Now i remember it wasn't a 2" but a 2 1/4" i found on the footpath rated for 173psi

I agree that 1.5" barrels are better than 2", but I do not agree with this guy that anything above 2" sucks.

2.5" SDR-21: soda cans/tennis balls
2.5" SCH 80: racketballs
3" SCH 80: water bottles
3" SCH 40: gatorade bottles, many other bottles throughout the house
4" SCH 40: toliet paper rolls (ultimate TP machine jk)
5" SCH 40/80: 2 liter bottles
6" SCH 40: canteloupes, small pumpkins
8" SCH 40: soccer balls
10" C900: basketballs

And this is only a small fraction... large barrels rule, if you have a big enough gun to handle it

PS: I know "pimp" isnt even here anymore....

EDIT: 2" SCH 40 isnt horrible though... some things fit great in it

i have 1.5 in barrel and i cant fit golf balls

Anyone else notice this is from almost exactly a year ago? The posts from Boogieman and BC should give it away.