The Countryline brand of augers is the third brand that I've owned. The first two where very difficult to dig in hard packed clay. They mostly just spun around a lot and it was a challenge to get them do anything. Out of desperation I bought the Countryline brand and gave it a try. It shocked me how easily it went through my soil. In fact, it dug so quickly and easily that I had to relearn how to dig holes because it would bury itself if I wasn't really careful. This was all with a 12 inch auger. You need to be super careful in how much pressure you put on the auger, and how long you let it dig before pulling it up and cleaning out the hole. Lots and lots of up and down.
No matter how careful you are, you will bury it. I have a 4 foot pipe wrench to turn the auger backwards, out of the hole. This is very difficult to do, so I add a 6 foot long pipe to the handle to get more leverage. First time that I did this, I used a 3 foot pipe wrench and I broke the wrench.
One day I got the crazy idea that if I had a smaller auger, it would be easier to pull up and I would have less trouble burying the auger in the ground. It turns out that the opposite is true. The smaller auger digs even faster and easier then the bigger one. It's extremely difficult to control and keep from digging too fast. The last time I used it, I bent the drive shaft that powers the auger. My tractor is 35hp and I'm unable to control how quickly that auger goes through my soil. I might sell it the 9 inch auger, or just remove the cutting teeth off it for my 12 inch auger and throw it away. I don't want to use it again.
With your super small 6 inch auger, I would be super apprehensive of how quickly it goes through your soil. As already mentioned, just idle your engine and take it super slow. Keep the hole clean by lifting it out of there over and over again. And most importantly, have a plan on how to get the auger out of the ground if you bury it!!!