What is the relation momentum and kinetic energy in a bullet? I don't know how to phrase this question but here goes. Suppose that a 7 gram bullet is traveling 1600kph, can a 1600 gram object(compose of the same material) traveling at 7 kph stop the bullet? Mathematically, it can.
But how do i incorporate kinetic energy into this, I know that the kinetic energy in the bullet is far larger then the object, but how does that work? I mean on one hand, momentum says that the bullet and the object should come to a stop, on the other hand kinetic energy says it should rip through that object. I am not sure, how these two concept complement each other
 A: Momentum is always conserved. So, your conclusion that the bullet will be stopped by the large, slow-moving object is correct. Kinetic energy, on the other hand, is not usually conserved. In your situation, all movement stops, so kinetic energy is zero afterwards. This is fine. Total energy is always conserved, so the energy that was originally kinetic needs to be found somewhere else. Here, it will be in the heat generated by the friction that causes the bullet and object to stop.
A: I'm assuming that your bullet and your target are traveling initially in opposite directions.  In that case they have equal and opposite momenta, and the momentum after the collision must also be zero.
When you have a collision where two objects stick together (or otherwise move with the same final velocity), there exists a reference frame where the final kinetic energy is zero.  This is called a perfectly inelastic collision: it's the most kinetic energy that you are allowed to lose while still conserving momentum.
A: Momentum is always conserved. Kinetic energy is not necessarily conserved.
The total momentum after the collision will still be zero, but the bullet will not necessarily be stopped by the heavier object. Both objects could keep moving in their original directions, but with lower speeds - ie the bullet passes through the other object. Only if the bullet is brought to rest relative to the larger object will they both come to rest. Alternatively they could rebound from each other, each reversing direction.
Which outcome happens cannot be predicted from the information you provide. The larger object could be an enormous sheet of tissue paper. Then the bullet will easily rip through it. Or it could be a large balloon filled with oil. The bullet may again slip through it. To predict whether the object will be ripped apart, you need to know about its internal strength and the length of the path through the large object. For the oil, you would need to know about how the drag on the bullet varies with speed and cross-section of the bullet. The object could be so hard and dense, or so elastic, that the bullet bounces off it. 
How much kinetic energy is lost can be calculated from the coefficient of restitution (e), which is the ratio of the relative speed of separation to the relative speed of approach. The value of e cannot easily be predicted; it is usually found by experiment, and applies only within a certain range of relative speeds. If e=1 the collision is perfectly elastic; no KE is lost. If e=0 the collision is perfectly inelastic; some (possibly all) of the KE is lost. If viewed in the centre-of-mass frame of reference (as in your experiment), a perfectly inelastic collision results in all of the KE being lost (dissipated).
