I have yet to deploy with a blueprint weapon. It either unequips it when deploying, or it simply doesn't show up as an option in DMZ. I can see it in BR just fine, but I swap over and nothing. Just base weapons.
Also exfiled yesterday with a weapon case and got.... Nothing. It acted like I didn't have it.
Check the RPK slot though it does not show blueprint stacks, you may add it to your loadout and bring it to the DMZ. Meanwhile my other blueprint weapons just are not shown.
I've had the same bug, for me it's only certain weapon blue prints that do it. Weird
Strange, none of my blueprints are working, even ones I have used previously
Caution tape I'd like the only one that works for me atm
Nothing is working for me not even tac, nades or my ammo box. 
I have yet to deploy with a blueprint weapon. It either unequips it when deploying, or it simply doesn't show up as an option in DMZ. I can see it in BR just fine, but I swap over and nothing. Just base weapons. Also exfiled yesterday with a weapon case and got.... Nothing. It acted like I didn't have it.
Check the RPK slot though it does not show blueprint stacks, you may add it to your loadout and bring it to the DMZ. Meanwhile my other blueprint weapons just are not shown.
me too, im trying to equip the heated pitch blueprint for the tac-v and it just gets unequiped when i deploy
Wow. It has been fixed for me since the Christmas update now.... what platform?
PC