I'm new to GMing Dark Heresy, though I'm fairly familiar with the universe, and I ran into a question in my current campaign. I know that some technology, especially xeno tech, is heretical and would be very frowned upon by members of the Adeptus Mechanicus. That said, can some of the more common weapons (like a lasgun or chainsword) be made heretical in some way (maybe by the addition of a piece of xeno tech or the like). The question arose because I want my players to face some enemies who have weaponry that I don't want falling into the hands of the players, due to its powerful nature.
The players are coming to the end of the current story and have narrowed in on the head of the cult they are investigating. I was thinking of having the boss have a chain axe, but I don't want the guardsman of the party to pick it up after (something I'm sure he would do given the chance). Is there any lore that I could use to explain how he cannot use the chainaxe, because it would be heresy. There is a tech priest in the group who could identify the heretical nature of the weapon if need be. What would that nature be?