Hi sorry if this question has been asked and answered already but my dad has had a historic arms semi auto converted Bren Mkii for a while now but never got the chance to shoot it until the other day. Out at the range we shot about 10 rounds out of it, it ejected the backside of a casing but not the whole thing. After that it felt like the charging handle went limp and almost like it wasn't pushing the round far enough, we couldn't find the rest of the casing. Any ideas? thanks in advance!