We had the same sort of thing for the M72 LAW - a 20mm (might have been 22mm - it's been 20+ years) rocket inside an insert in the fibreglass casing. Not exactly an AT round, but you still wouldn't want to get hit by it!
The 84mm Carl Gustav also has/had a training round using a 7.62mm tracer (I think). Absolutely NOTHING like firing real rounds, but it was useful for practising your aim and actually hitting the target before being allowed anywhere near the rather more expensive HEAT rounds (something like $10,000 per shot I think).
A mate of mine was working collecting shopping trolleys and was teased for doing what was seen as a dead end, low pay job. He shut them up quick when he mentioned he'd just blown through $100,000.00 of ammo on the weekend as a reservist.
