I have a Yugo M48 Mauser, chambered in 8mm, and I have similar experiences with my barrel heating up. While it may be "warm" after 20-30 rounds, that is only the pieces directly attached near the end of the barrel.
After I shoot a 70 round bandolier through it (with agin 1954 ecuador ammo, fairly hot loads I believe), anything that is metal gets very hot to the touch. After about 110 rounds, anything you touch metal, aside from the bolt and the stock, will pretty much guarantee a burn, and the stock is fairly warm too.
The most I have ever put through it at onetime, was probably 110 in about 30 minutes, and then I let it sit for about 45 minutes because the heating was causing ammo feed problems...
My shot patterns go high and to the right after a lot of heat on the barrel...
It's not hot until both your hands and the stock are dripping with sweat, so don't worry about it.