Warhammer 40K Tabletop VII: Common Sense is not RAW.

[Cheesegear]

I'm talking about things that Ordo Hereticus Inquisitors should be able to get, like hellpistols and powerfists.

What's up with this?

Maybe you should ask GW?

But, are you really worried about your Inquisitor not having access to Hellpistols and Power Fists when you have access to Inferno Pistols and Power Stakes, and Chuirgeons, Penitents and Crusaders and Mancatchers for your acolytes?

Witch Hunters can't get power fists because the designers decided it should be one of the differances between them (it's kind of moot since hereticus can use their pseudo chainfists). Same as how they don't get terminator armour.

Daemonhunters have Eviscerators too. Usable by Grey Knights, even.