recoil ~ or "kick" in a marker

• 11-30-2011, 06:31 PM
Pyrate Jim
recoil ~ or "kick" in a marker
I need to think this one through....
If recoil is an effect of linear force, the burst of gas exerts equal force, action pushes the ball out the barrel and reaction pushes back against the bolt face...
That linear is the line parallel to the barrel and pushing back against the mass of the marker.
Most markers today are so light that that major portion of the mass is the paint in the hopper.
If the largest mass is above the line of recoil, would that make it "kick" downward?
• 11-30-2011, 07:51 PM
DarkApollo
You forget the reciprocating mass of the bolt. That is where the kick comes from.
Quote:

Originally Posted by Pyrate Jim
I need to think this one through....
If recoil is an effect of linear force, the burst of gas exerts equal force, action pushes the ball out the barrel and reaction pushes back against the bolt face...
That linear is the line parallel to the barrel and pushing back against the mass of the marker.
Most markers today are so light that that major portion of the mass is the paint in the hopper.
If the largest mass is above the line of recoil, would that make it "kick" downward?

• 12-02-2011, 06:20 AM
GEE TEE
Although... given the low weight of some modern bolts, ram assemblies etc. the effect is becoming increasingly minimal

I had a deadlywind hollowpoint bolt in one of my ION's that only weighed 7 grams. Needless to sat the kick compared to stock SP bolt was almost non existant. Another thing to consider is with markers becoming featherlight inside and out, the kick back from propelling a ball from the barrel will become more noticable, and that will always be present due to simple physics.
• 12-02-2011, 08:51 PM
athomas
The force acting on the ball is also acting on the front of the bolt. The bolt is held forward by whatever mechanism that pushes it forward. It could be a mechanical mechanism or pressure. It doesn't matter much. It is essentially part of the gun. However, the ball mass is much less than the mass of the gun so the ball moves away from the gun. The equal force is still pushing back though. The force that is propelling the ball is also propelling the gun. No matter how you slice it, that energy has to go somewhere. If you were to place your hand at the end of the barrel and it got hit by the ball, it is the same amount of energy that the gun is moving back into your firing hand with. Its just that the gun with its greater mass does not reach the same speed. Therefore, the perception is that firing of the ball does not produce much kick. This is also partially offset by the fact that most guns start to release air as the bolt mechanism is moving forward so the stopping of the forward motion as the bolt changes direction (energy transfer forward) offsets the push backwards by the air firing the ball.

The moving mechanism in the gun can sometimes be a major part of the mass of the gun. When this mass moves back and forth, it does affect the movement of the gun. The backwards motion is the kick that most people feel when they fire a paintball gun. The forward motion as mentioned above is somewhat offset by the firing of the ball which is why the guns don't kick forward before they kick back. The backwards motion of the bolt and mechanism causes pushes the gun to kick back when the mechanism comes to the sudden stop at the end of its travel. The reason most paintball guns kick the barrel up in the air is due to the gun rotating back across the trigger hand which acts like a pivot point.

As mentioned by others, as the mechanism and bolts get lighter and as the mass of the guns get lighter, the mechanical effect is reduced and the recoil due to equal and opposite force given to the ball-gun combination becomes a greater part of the equation..
• 12-02-2011, 09:01 PM
sQuidvision
the last post said this but in less clear english :p

You are forgetting that the MOST mass on the gun is your hand and arm... which unless you are a gangster is located BELOW the linear force, therefore the recoil will be upward.

:cheers:
• 12-03-2011, 08:23 AM
athomas
Quote:

Originally Posted by sQuidvision
You are forgetting that the MOST mass on the gun is your hand and arm... which unless you are a gangster is located BELOW the linear force, therefore the recoil will be upward.

Which is why I mentioned that it rotates back a cross the trigger hand. The hand and arm combination doesn't move back because of their combined mass but the energy pushing back is still enough to cause rotation because the wrist is not as strong in the rotational direction and the in-line gun/barrel has a mechanical leverage advantage over the grip part where the hand holds it.
• 12-12-2011, 03:27 PM
bjjb99
Quote:

Originally Posted by athomas
Which is why I mentioned that it rotates back a cross the trigger hand. The hand and arm combination doesn't move back because of their combined mass but the energy pushing back is still enough to cause rotation because the wrist is not as strong in the rotational direction and the in-line gun/barrel has a mechanical leverage advantage over the grip part where the hand holds it.

Definitely agree.

The rearward force is converted into a torque, acting about the point of rotation (one's wrist, an essentially static point since a person is much more massive than a paintball gun). The distribution of mass about that point of rotation serves as a moment of inertia, against which the torque acts. The result is a rotational acceleration.

Since one's wrist is generally located below the rearward-directed force, the resulting rotation causes the barrel tip to move upward. How much rotation is determined by (a) the magnitude of the rearward-directed force, and (b) the amount and distribution of paintball-gun-related mass relative to one's wrist.

BJJB