In sire referencing schemes (SRS) genetic links are formed among flocks by the mutual use of some rams (reference sires). These connections allow for across-flock genetic evaluations offering a larger pool of candidates for selection. Where SRS have been established in hill breeds, their guidelines have been adopted from terminal sire breeds. Hill flocks, however, are typically much larger in size than other pure breeds with more candidates to select among within individual flocks. Guidelines from other breeds may therefore be inappropriate. Using stochastic simulation, the objective of this study was to explore the effect of number and method [artificial insemination (AI) vs. natural service (NS)] of use of reference sires (RS) on genetic gain, inbreeding and connectedness for a lamb trait (weaning weight) in SRS tailored to characteristics of hill breeds.