Why not make all MG rounds tracer-illuminating?

Will it have been too expensive back in WW2? Will it blind a shooter at night? Will it make the shooter too visible and put him at greater risk? I understand this was done in Vietnam and subsequent wars.

 

Im only aware of two types of tracer (maybe more im sure) - one is a designated tracer, burns bright and is NOT a bullet...put maybe 1 in 5 or 6 or 10 in the belt.he other is a powder charge behind the bullet that ignites and spews smoke...good for air fighting...but not night fighting.

 

I can't think of an advantage to this?
If a ratio of tracer is useful at 1:4 or similar, why would you need more?

One ballistic reason why not:
BASIC BALLISTICS

There are chaps on here with more 'practical' experience, though.
Doubtless they'll chip in.

 

Because every fifth round is sufficient for tracking where your bullets are striking. Ball rounds are less expensive and while the trajectories are similar enough for their intended purpose, tracers lose mass as their pyrotechnic burns off so their trajectory does vary from the ball rounds. No, firing all tracers was not a common practice in Vietnam and subsequent conflicts, four to one (every 5th round, 4 ball, 1 tracer) is still the norm. Loading additional tracers as the last rounds in a magazine is/has sometimes been done to alert the shooter that he's about to need a mag change, but this also alerts the enemy so it is not really common. Squad leaders sometimes load all tracers in some mags to use for designating targets for their troops, but it has the unwanted consequence of also alerting the bad guys to the leaders position. So why would you want to fire all tracer?

 

I had the idea it had a strong psychological effect. Not much advantage if that's all it provides. Aside from squad leaders using all-tracer to designate targets, it was also sometimes loaded into the bottom 10%-20% of the magazine or belt to alert the user that he's running out of ammo. It will also alert the enemy though.

 

One would think with night vision and infra red sights (and sights in general)...tracers are being used less...Never heard of it having a psychological effect...I think all heck breaking loose in (near) complete darkness would freak me out more...

 

Tracers use several very harsh metals or salts to create the flare you see, and the residue of such is extremely corrosive to both the barrel and moving parts in the action. The residue can also, anecdotally, lodge in the gas port and shut the entire gun down. That is why it is recommended to use the lowest ratio of tracers to ball rounds that will be useful in directing fire (one tracer per 4 or 5 round burst); with the subsequent ball rounds, theoretically, helping clear any residue left in the barrel by the tracers.

 

Someone put 1500+ tracers through a M60.

 

Put 1,500 rounds of ball through the barrel at that rate of fire and you have the same effect.

 

Hell...You can melt an AR with less rounds of ball.