I have a couple of Lee Speeds in .375EX 2-1/2in & a couple of barrels coming, I have tried all the magazines & I have told people on here before but all seem to ignore me, the .375Ex & 8mm magazine are the same as a normal .303, other than being shorter & having a follower similar to the SMLE, the .375 works better in the later SMLE magazine when I try them, I just did it right now stuck five .375Ex into a SMLE MKIII mag put that in my Lee Speed .375Ex & loaded them from that mag into the chamber & that was with out bending any mag lips/tabs, I think it could be even better if I did a little adjusting but it worked just fine, as it has many times before !

I load most of my rounds in .303 cases blown straight & long loaded but I had 5 .375Ex rounds to try from the Cartridge Collectors meeting, don't like to do that as it marks them up a bit !

PS I'm sure the No5 action will be up to the job !