Can you use the not yet released “Realistic Weapons Pack” for commercial use ?
Yes, you will be able to do that when it’s available.
Also, you can use all of the free Epic content in the marketplace commercially in any games you build with UE4. This includes all of the content residing in example projects. For example, all of the weapons, meshes, sounds and materials in Shooter Game. Tappy Chicken even!
Nice! Answered by Epic’s CEO and founder, Tim Sweeney!
You’re the best Tim!
When it will be released?
The weapons pack is at least a couple months away, but various free packages will be coming to Marketplace in the meantime.
Oh my God!
It`s Tim himself! 
I really want this Realistic weapon pack!
It will be very cool because in UDK we don´t have this great examples!
Cheers!
P.S.> Tim you are awesome! 