Testing Plumbata

[Renatus]

I wouldn't have guessed it's launched javelin-style, but if you had better results like this, I'll trust your word.

Don't trust my word.  I haven't been able to test these weapons.  I theorize that the Romans would, initially at any rate, have regarded these as another form of javelin and launched them in the way that they knew.  If that did not produce the results that they were after, they would have to look for alternative methods.  Some experimenters have produced results that suggest that fletched plumbatae thrown javelin-style could meet Vegetius' criterion of being able to out-range standard javelins but I would like this to see this thoroughly tested, particularly with regard to unfletched weapons.

Speaking of what types of troops were trained for it, was it a weapon that was issued should the need arise, but not each time, which would explain why it could sometimes not be used by frontline troops but also possibly used by logistical echelons?

The passage I was thinking of is Maurice's Strategikon 12.B.16:

'The heavy infantry, who are drawn up in the front line, advance still closer to the enemy.  If the men have darts (martzobarboula) or missile weapons they throw them, resting their lances on the ground.  If without such weapons, they advance more closely, then hurl their lances like javelins' (Dennis's translation).

This does not explain why they might not have had the weapon, whether by accident or by design.