We had this discussion in another thread. Weight carry limits are comparable between the last three games. As such, FO3 and FONV ARs (and there were several) came in at approx. 7 weight units...very much mirroring their RW weights (in lbs). The FO4 AR comes in at a hefty 27 weight units (4 times the previous entries ARs). Weapons in previous games generally followed actual RW weights; we don't have a clue as to where Bethesda pulled this new notion from...probably from the same place they pulled that AR from to begin with....but it is noticeable across the board for all weapons. Pistols, in general, only weigh roughly twice that of previous weapons.

And it all rings of arbitrariness.

Yes, we all know the perks and the mechanics to increase limits for each game. Bottom line: 27 weight units is noticeably higher.

It is more than likely just a ham-fisted mechanic of balance than anything...that feels like a giant step backwards.

Yup, that's what I call my .308 Combat Rifle.