"Have a question; If the 30-30 Winchester wasn't the first rifle cartridge to use Smokeless powder in the US which one was?"
As I said, it's a question/answer filled with nuances...
The first US rifle cartridge to use smokeless powder was the .30 US Army, or the .30-40 Krag as we now know it.
The first COMMERCIAL rifle cartridge to use smokeless powder is actually a two-parter, because the .30-30 and .25-35 Winchester cartridges were introduced at the same time, so they are co-owners of that title.
That's actually a good, if misleading and sneaky, trivia question.
Few more factoids...
The .30-30 and .25-35 weren't ready for introduction with the Model 1894 as had been intended. Winchester was having problems getting quantities of smokless powders suitable for the cartridges, so both rounds were rolled out in the 1895 calendar year.
The 1894 was introduced in that year chambered in the .38-55 and .32-40 cartridges, both blackpowder.
It appears that the .30-40 Krag was the third smokless rifle cartridge offered commercially, around 1897, for both the Winchester Model 1895 and the Winchester Model 1885 High Wall rifles.
Around the same time the 6mm Lee Navy cartridge was offered commercially, but wasn't much of a success, as the same problems plagued it commercially (metal fouling, lack of truly suitable powders for a high velocity small bore) as had been seen in military service.
"The gift which I am sending you is called a dog, and is in fact the most precious and valuable possession of mankind" -Theodorus Gaza
Baby Jesus cries when the fat redneck doesn't have military-grade firepower.