The Recoiless Cocker: Math and Theory

[El Pipi Fantasma]

The Recoiless Paintball Gun

Now, assuming that the gun has a bolt that moves backwards to produce recoil (I.E. Autococker), you would have to have an equal force moving forward in order to eliminate recoil. To do this, you must have the same weight moving the same speed at the same time in order to cancel the recoil. OR you can have a larger mass moving at a lower speed and end its movement at the same time as the recoil. OR you can have a smaller mass moving at a greater speed and end its movement at the same time as the recoil.

Now for the technical part.
Let us say that the autococker has 1/2 kilo of mass moving backward at 5 meters a second. You have a momentum of 2.5. In order to balance the forces, you need an opposite momentum of 2.5. Lets say you have a one kilo weight to work with. By simple math the mass would have to move at 2.5 meters a second.

Now the fun part: Distance Travelled
In order for this to work, the masses must start moving and stop moving AT THE SAME MOMENT. Now, the time is the same, and the speeds are established. Now you must determine distance. Lets say that the 1/2 rear mass moves .05 meters (5 centimeters). Let us also say that the masses complete their movement in .1 second (to make things simple). What we are trying to find is the distance moved by the frontward force.
We know that;
Backward mass is .5, it moves .05, and takes .1
Forward mass is 1, it moves x, and takes .1
NOW;
1/.5=.5
.05*.5=.025
And we have our distance. .025 meters

SO;
In order to balance a .5kg mass moving backward @ 5m/s and taking .1 seconds to start and stop, we must have a 1kg mass moving forward @ 2.5m/s and taking .1 seconds to start and stop.

All of this is fine and dandy, but how would you do it.
Well, what you could do (and I think is a good idea) is take some lead and make a hole in it big enough to fit around an autococker barrel (smoothe on the outside) you then add or take away material to get the right weight. then you take an autococker ram and modify it to travel 2.5 centimeters in .1 seconds with the weight attached. And Viola! You now have a recoiless gun.

I hope everything works out on the math. I think it does, but I would like others to check it so that I can know for sure.

Thanks for listening (reading really:p) I hope I made sense and that this post is followable.

[Redkey]

Start lifting weights to build muscle to control the recoil forces. The added benefit is that being a big buff type of guy will help you get chicks.

This seems like a alot of work to prevent a little recoil. What happens when the bolt closes? I assume you would have something like this work in reverse?

I think you might need to be concerned about the moment arm as well. If you considered your hand as a pivot point both forces need to be acting the same distance from the pivot point to cancel each other out. Been a long time since I took a dynamics class so I'm a little rusty on this topic. I'm pretty sure that both moving masses will also need to be in the same plane... The barrel sits a bit higher than the center of the back block so you might need to include that in the calculation.

Plumbing it would probably take another three way or solenoid valve. Plus, you would be using extra air so your shot efficiency would drop.

You'd have to control the timing very precisely too... in order to cancel each other out, both events would have to occur at the exact same time. People have a hard enough time timing one cocker three way... Imagine trying to time two of them.

If you do decide to try this project, please keep us posted.

[El Pipi Fantasma]

What my thinking is that if both forces act in the exact opposite direction then they will cancel no matter how far from the pivot. There is only a pivot BECAUSE of the recoil. The reverse action you speak of is what I was thinking when I said to use a modified ram. I failed to say that it would be connected to the three way and reg, just like the other ram. I don't think that there would be any extra aclculations, as the twising motion of the bolt because of the weight of the ram and the cocking of the cocking rod, would be neglegable (big word I spell wrong every time). You would probably need slightly more counter-force weight on the bottom of the front assembly to counter this, but it would be a small ammount. The rams would also have to be end to end for there to be no turning effect of the gun at cycling. i.e.

----> is a ram
----- is the gun

<----
---------------
----> You get a counter-clockwise turn

<--------> No turning forces

Anyway. I am not really thinking of doing this, I just wanted to know if my thinking was sound, or if it was based on a perfect world, which we all know doesn't exist. If it did, paintball would be cheap!

[FreshmanBob]

personally i think the effect of the recoil of a cocker is small compared to the movement of your trigger finger

so why bother?

[El Pipi Fantasma]

I know, I just wanted to know if my thinking was correct.:D

[P8ntballerAK]

you are wrong about the pivot point. no matter how sharp accurate or timed it is, there wil always be a small pivot point somewhere if there is movement. If this werent the case then you could have the opposite reaction on the tip of the barrel and it would have the same effect as it would close to th bolt. It would be like a teeter totter, if it were on the tip of the barrel it would require less energy to keep the gun stable then it would next to the bolt.(this is real hard to explain)

Think of it this way, you have a 2x4 piece of wood and you need to keep one end steady. what will be easier holding the end that needs to be steady or trying to hold the opposite end? holding it on the end that you need to keep steady of course.

[xatle]

[]...[]<---2 seperate, shorter bolts of equal weight
..\./..<---actuater arms hinged to the bolts
...|...<---ram, pushes up on the actuater arms forcing the
...|...bolts apart(closing breach), etc.


if someone worked out a cocker with this sort of bolt system then the only recoil would be from the hammer, the ram, the air flow, and the paint ball.
is this sorta what you were thinking?

[El Pipi Fantasma]

Not what I was thinking, but yours looks simpler and easier;)

[pbjosh]

Uhm,

Well, I have a couple of thoughts here. The biggest thing that gives you the recoil is the firing of the ball. The angle between the barrel energy release and you hand also factors into the equation. If the barrel released air at the same level as your forearm, you would have less recoil.

To make a counter-acting event as strong as the gun firing you would need to release the same amount of energy on the same level from your hand, or a lower amount higher frm your hand (loader mounted) or a larger amount closer to your hand. And we are talking about a 2-4 ms time period. So a ram activated mass would have to run at high pressure and fast to counteract the shot. Or you could have a vent on the tip of the barrel that you could adjust to blow the tip back down.

All in all, good luck. Or you cold get a stock that transfered the energy back into your shoulder. Like a rifle. Ha!

Josh