More projectile ammunition and more guns that use them.
Some sort of projectile (pellets, bullets etc.) made from lumps of steel/scrap metal, which can be used on the pneumatic assault rifle and which have some decent penetration (I might actually do this myself since I like the pneumatic assault rifle so much).
Pellets should only require metal cutting and fine hammering, stronger stuff should require the usual crucible/mold.
More things using molds and melted plastic (like plastic canteens), more craft-able energy weapons.
Basically weapons that a low str character can make and use early on, since its paradoxical to require strong weapons to get to strong weapons (i.e guns)