Dune6 tire mounting

[tropics]

Hi,
I have a couple of never mounted 17x12 Dune6 wheels. The Tire shops say this rim is unmountable due to the barrel design, its only this rim design in the 17x12 size that has the problem. One shop tried to mount a tire and said that the barrel doesnt dip enough down so the tire lips cant be seated and mounted. Several other shops (off road large tire mounting shops) I also called have mentioned the same experience. Any insight on this, I cant believe that the previous Weld Wheel company designed a rim which wont accept a tire. Is there a special trick to mounting a tire on this rim?

Thanks

[Weld 3]

The only way I know how to get a tire on these wheels is to do it by hand. It may take several people to accomplish this. Dismounting could be even harder. The previous company made some of these wheels without a good drop center.