# this may help

May 26 2002 at 9:26 PM
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I don't know how to calculate it theoretically...but if the chamber is already built and you have a 1.5:1 chamber volume to barrel ratio(assuming this optimizes force from chamber) barrel to attach to it...you can find the force exerted on a projectile...this is kinda lengthy though...

Find a heavy round object to use as a projectile this will nearly eliminate error from air resistance.

Measure the length (in meters) the projectile will travel in the barrel. Call this D1.

Find the mass of the projectile( in Kg's). Call this M1.

Fire the gun nearly vertical(so you don't get konked on the head) and time the flight from ignition to impact. Divide the time in half. Multiply this by acceleration due to gravity(9.8 meters per second squared) and this approximates velocity of the projectile, call this V1.

Divide V1 in half to find the average velocity of the potatoe inside the barrel.

Divide V1/2 by D1, and this will give you the time in seconds that the projectile was in the barrel. Call this T1.

Divide V1 by T1 to find the net acceration of the projectile in the barrel. Add the acceration due to gravity(9.8 m/s) to give acceration applied to the projectile. Call this A1.

Using F=MA, multiply A1 by M1, and this will give you the force exerted on the projectile in Newtons.

This method assumes that the barrel is at optimal length and uses non-calculus based physics, so it is just an estimate...If this didn't make sense or something like that or if someone thinks this is completely wrong...feel free to ask or comment.

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Responses

1. Re: this may help - Anonymous on Jun 4, 11:25 PM
1. Re: Re: this may help - Anonymous on Jun 4, 11:26 PM

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