That's common with NULA's of all barrel weights.
In fact they normally shoot just as accurately with the barrel screaming hot as with it cold, and to the same point of impact as well. That's one reason I often use my NULA .30-06 as a scope-test rifle: I can keep shooting without letting the barrel cool down, getting results a LOT more quickly than if I had to cool the barrel down between shots or groups.
The same applies to the one Forbes Rifle I've tested as well.
