As stated, there is still brass and ammo avialable. Hornady makes two loads, a 225 grain and a 270 grain. Both are loaded to the same velocity. The current price seems to be around $2 per round.
The 225 has significantly less kick.
Forgot the second half of the question. I have only fired a max of 40 rounds in a session. The max range I have tried is 300 yards. At that range the accuracy was not to hot with the built in bi-pod, it is too flimsly. Up to 200 yards the gun was field grade accurate. I am not a bench rest guy so this was good enough for me.
I did not notice any temp issues.