When Steve sends the knife on a pole up to Lucky to cut down the kite, he ties to rope near the blade. But, in the next long shot, the tool is going up to Lucky with the blade down. In the following close shot of Lucky getting the tool, it is tied near the blade again.
Although it is repeatedly stated in the film that Lucky and Steve are brothers, there is no explanation as so why they have different last names.
Lucky keeps his gun unconcealed in an unlocked cabinet in a common area at work, and there is no explanation as to why he has a gun or where he got it in the first place.