It appears that tinwalt is expressing his usual ignorance - BREN can’t fire tracer & other ammo types due to the mag shape? wtf? Of course it can! The only external difference visible between a round of ball & other types is that there’s a bit of paint on the tip of the other rounds!
OK, so now to correct some other wpn illiterates around here:
Stg44 is NOT an LMG, it’s an assault rifle. Different role, different type of cartridge, different application, different crewing (ever heard of an assistant gunner on an assault rifle?) You try putting down bursts of suppressing fire with a Stg44 at 3-600 hundred metres (which is the role of an LMG). I’ve fired one full-auto, and the muzzle climb is excessive, and by the third round, the muzzle is significantly higher than when you started.
The top mounted mag on the BREN allows a larger mag to be fitted, and also for the firer to adopt a lower prone position (eg. bipod folded, resting on a sandbag) than is possible with the BAR (such a position is limited in the upwards arc of fire by the mag sticking out the bottom). The top mounted mag also allows the assistant gunner to change mags extremely quickly, which is not possible on the BAR, since it needs to be tilted to the side to allow the assistant gunner to put the next magazine on.
The only things that could remotely be seen as copied from the Stg44 into the AK are the overall layout (which is pretty much common to all box-fed rifles with pistol grips by necessity) and the gas system, and even then, only really the gas tube itself (the tube has ridges so that once the head of the piston has left the gas cylinder it is only in contact with 4 points in the gas tube rather than the whole tube (as it does on e.g. the SIG 550, Garand and many others). This makes it less sensitive to dirt and fouling). The bolt principle is different (carrierless tipping bolt for the Stg, rotating bolt with carrier for the AK), the control layout is totally different (stg has crossbolts for safety & fire selection, AK has that awful single lever on the right hand side, mag release is a thumb button for the stg & the mags push fit, AK uses rock-in mags & has a flap in front of the trigger guard).
The BAR is really rather too light to be a serious LMG, and has no quick-detachable barrel, which is necessary for any level of sustained fire. It’s rather a sort of “machine rifle”, or heavy automatic rifle, in the way that the RPK47, RPK74, or Enfield L86 LSW are. It’s a slightly awkward 1/2 way house between a rifle and an LMG. The bipod-equipped versions were a bit better, but were rather heavy for what they were - a heavy rifle with a limited ammunition capacity, and the forend still caught fire if you put too much sustained fire through it. It was designed for the 1st world war to deliver “walking fire” from the hip when assaulting trenches to keep the heads of the bad guys down, and was forced into the LMG role largely for lack of anything better in the US. A testiment to its lack of success as an LMG is that the US army considered that there was a firepower gap at section level, and stuck a butt & bipod on the M1919 Browning machine gun (making the M1919A6) as an interim solution to give the squad more mobile firepower. If you take the BAR for what it is, it does the job it was designed to do and does it well. However, when trying to force it to act like a rifle or a true LMG, it doesn’t do either brilliantly.
This talk of a higher muzzle velocity counting towards the BAR being better is silly: both the .303" and .30M2 have more than adequate combat ballistics and are both equally good from an LMG, MMG or GPMG. .308" 150gn @ 853m/s vs .311"175gn @ 744m/s is not a huge difference ballistically. From personal experience, however, .30 M2 is a far worse recoiling cartridge than .303" Mk.VII.
A high rate of fire is not also necessarily a good thing - at 550rpm, the BAR mag is emptied in a little over 2 seconds of continuous fire, which is not terribly controllable, or indeed controllable at all without a bipod. The main complaint against the MG42 both in the light (LMG) role and the heavy (MMG) role was its rate of fire. It may have sounded scary, but it munched ammo at an astounding rate.
Tinwalt - you seem to be playing “Top Trumps” between the BAR and the BREN with these stats.
A real test would be to have the BREN and the BAR next to each other on the range, and to have them fire whole mags at a go at a single target each for a minute, with assistant gunners plus all the standard gear. I can guarantee that the BREN will fire far more ammunition and score far more hits (and will have changed barrel once), and the BAR will be a smoking U/S wreck by the end of it, if it makes it that far.
Another point. There are some people here who have a lot of experience with large numbers of different types of firearms, and others who are google experts. The latter should learn from the former, who include Preatorian, Cuts & others.