Linking a rifle to hands?

Deke

In Daz Studio I have a soldier figure and am using an aniblock for his movement. This particular block has hands like he's clutching a rifle, but there is no rifle. So my question is if there is a way to link an imported rifle to the hands?

I have put the rifle in position in the first frame and parented it to the right hand. The movement in the block pulls the rifle away from the left hand, so is there a way to link the left hand to a particular part of the rifle?