Dont know why you oppose it. Everyone else seems to like it.
1.) The hand is too near to the end of the hand guard and makes the blockhead's invisible arm seem very long and odd.
2.) He pulls out the mag and then jams it back in, no sign of him dropping it and getting a new mag.
3.) Dust cover animation is a little stiff and the bullets don't appear to come out of it, instead coming out of the carry handle.
4.) Model overall is lacking in details, doesn't really look like an M4.
5.) Reloading animation is done incorrectly, the blockhead takes out the mag with his left hand and then does the rest of the reloading with his right hand, this makes no sense at all.
6.) During reloading, the blockhead turns the gun and pulls back on nothing, on a real M4 you don't turn the gun and pull back on nothingness.
Instead you push down the bolt release.
7.) Fixed stock clips into minifig's shoulder, looks very odd. A LE stock would look better in my opinion.
Hope my post was constructive and helps you improve.