When the Cardinal is breaking into Camp David, he shoots the guard at the gate who falls to the ground with an AK-47 across his body. The AK-47 is a Russian military weapon. The standard issue rifle for United States troops is the M4/M4A1.
At about 30 minutes into the movie, when D'Artangan and Athos are trying to get away from Winter, D'Artangan puts something in the microwave, then turns on the oven and leaves the door open, and shortly after the house blows up. The stove in two scenes is clearly an electric stove, not gas, so therefore would not explode for any reason.