I didn't have any putty or Play Dough handy, so I cut a couple rectangular strips of low-grade (thin) paper towels and laid them in the barrel channels. With the paper in place I couldn't come close to snapping the forearm shut. The last fuzzy picture shows the end of the forearm with no paper and snapped shut. It seems to be fitted pretty close. A chance for a long, lean splinter or perhaps a lean(er) semi-BT?