Large upper critical fields and high critical current densities at low temperatures make the iron-based superconductors (IBS) promising candidates for high field magnets. However, they have to compete with cuprate superconductors that have even better intrinsic properties and their conductor technology is much more mature. In both these classes of materials, the suppression of the critical current across grain boundaries impedes a cheap conductor production so far. It is well established that this grain-boundary limitation is less severe in the IBS but still unclear whether grain coupling could be strong enough in untextured or weakly textured wires to enable cheap production technologies such as powder-in-tube (PIT). Potassium doped Ba-122 achieved the highest critical current densities in PIT wires and tapes so far, its reason still being unclear, since thin films and artificial grain boundaries of this compound have been realized only recently. Thin films of K-doped Ba-122 films were grown by molecular beam epitaxy on strontium titanate bi-crystal substrates with a 50 nm thick BaFe2As2 buffer layer. The magnetic field profile above 24°, 30 °, and 36.8° boundaries were mapped by scanning Hall probe microscopy. The currents crossing the grain boundaries were derived from the inversion of Biot-Savart’s law. First results indicate undisturbed current flow in some areas of the grain boundary.