Do Magma Armor and Flame Body's breeding effects stack?

Question

All combinations of it: Multiple Magma Armors, (ex. Magcargo + Camerupt) Multiple Flame Bodies, (ex. Volcarona and Magmortar) and a Magma Armor plus a Flame Body. (Camerupt + Volcarona)

Yes, I know "stack" isn't the right term, but you get it.

Answer 1

No.
>Although Hatching Power can stack with the effects of either Ability; the effect will not stack up if multiple Pokémon with Flame Body and Magma Armor are in the party.

Unfortunately having more than one will not help you. You can still use the Hatching O-Power though, and its effect will stack, so consider using that instead.
Source

Comments

I do use that O-Power, and I find it helpful. Thank you for your answer.

Answer 2

No, it doesn't.
Sadly, it doesn't work, it will still have the same x2 steps off of hatching the egg.
However, I suggest you use the Hatching O-Powers, as they can help quite a bit.
Hatching O-Power Lv.1 shortens the time by 1.25x
Hatching O-Power Lv.2 shortens the time by 1.5x
Hatching O-Power Lv.3 shortens the time by 2x
So, if you have Hatching O-Power Lv.3 activated, you can have the effects of two flame bodies for the price of one flame body in your barty!
Hope I helped!
Sources:
Source1
and
My giant brain!