Big Guns Never Tire question

[exeteroborach]

So can Monsters/Vehicles, while within engagement range of enemy models, fire out of combat too or just into their own combat? 
Reading the rules, it doesn't seem like they can but I've heard a few people say they can. 
Thanks. 

[Jbizzy]

Out of combat is okay. Still -1 to hit.

I think blast still can't shoot out.

[exeteroborach]

Thanks. 
Yeah, there's a picture of the situation in the rules commentary I missed. Pretty clear actually.