Bug -- Guaranteed Rare gives Rocket Launcher

[Quantum]

Almost every time I craft Guaranteed Rare items in the base, around 5-10% of them end up as Rocket Launcher, which is always Common. It never gives any other Common item, this bug only happens with Rocket Launcher.

[SawzAll]

I don't know if it's a bug.

And I ran stats on the "chance of rare" a long time ago when I started playing.  I found that building only common items was more efficient for boosting items.  When I got a factory and started building power kits, this only boosted my efficiency even more.

I'd recommend just building common items.

[Quantum]

If it isn't a bug, it is at the very least misleading, since I am led to believe I will be getting a rare card but I get a common one that is no better than other commons in any way.