Every time I type into the console “impulse 101” I haft to wait and when it’s loaded, it bugs the sound then the game freezes! :’( It makes me rage!! 
can somebody fix this for me?
Did you first type into the console “sv_cheats 1”?
well at first I did, then I did it second time. but at first time it froze. and then it done it again!
It freezes for me too, but I think it’s because the game has to load all these new viewmodels and HUD icons at once. When I type it again just to refill ammo, it doesn’t freeze anymore. I think it’s normal behavior.
Yeah, same. I assumed it was just the engine trying to handle all the load at once, though it never freezes for more than a few seconds.
but mine takes a eternity!! 
Remember, this is a cheat and should not be construed as a bug. Mine took forever to load, too. It might be your computer setup.
I’m running black mesa on windows 8.1…
Not just your OS, it also could depend on your hardware, or other software you may have running simultaneously, possibly in the background.
The first time ever I used the cheat, it worked, second time did and third. but fourth and fifth time it froze. so, IDK…
maybe it depends on the type of ground material you are standing on, because impulse 101 just spawns all the guns at the player’s location and the ones you don’t need/already have can sometimes fall through the ground, which could sometimes cause a crash
anyway try updating source sdk base 2007 and also verify steam game cache.