Steyr AUG's Just Don't Melt!!!
Here is the evidence from the designer of the F-88
Nick- - - On the Steyr Aug melting . . .The testing which was conducted on the AUG actually cost nearly as much as developing the rifle itself! It was the first "torture-testing" of its kind. During this , the rifles were fired underwater, immersed in mud for days and then fired, put in ovens for days at a time and then fired , a Unimog was driven over one F-88 30 times before anything snapped and even than the rifle was able to fire, metal rods were hammered into the barrel and than the guns were fired. Finally the Steyr AUG was given to the hardest climate on earth - Australian outback - even their the rifles performed flawlessly. This reliability can probably only be matched by the AK or in any case very few weapons.
There has been several myths about Steyrs "melting" during firing - these are largely myths. The only case which I am aware of a Steyr actually melting was in 1995 in Singleton. It occurred during a battalion firing exercise. After the shoot was over , one of the firing range safety officers collected all spare ammunition he could find - 25 magazines in all. He fired them one after the other on full-automatic. Needless to say the gun jammed due to the barrel expanding from all the heat generated and part of the polymer stock melted. It was than estimated that the rifle heated up to 500 degrees Celsius - conventional rifles would jam long before that. Other than in the extreme case stated above , the F-88 is not prone to "just melt".