Active Yb-doped large mode area (LMA) fibers allow for power scaling of lasers with excellent beam quality up to the kW regime [1]. However, the demand for compact, robust and cheap high power sources pushes research towards integrated, monolithic fiber setups. Most prominently, intra-core cavity mirrors can be realized with fiber Bragg gratings (FBG). However, in contrast to single mode fibers, FBGs in large core few mode fibers are challenging for two reasons: Firstly, conventional fabrication of FBGs in fibers with large cross-section is time-consuming and costly. Secondly, multimode interaction in few mode fibers leads to modal instabilities and polarization effects [2].