Ok, I would like to simply answer a question, rather than give an opinion. The answer to the question of "can I use my gas auger bits with the Clam Auger (drill) adapter?" is a simple "YES". It will cost you $10 and about an hour of garage tool time!
I too had this question as I have several "gas" auger bits, and did not wish to purchase something else (another hand auger) in order to use my Clam auger adapter.
First, you will need to purchase a brass machined bearing sleeve that steps from 3/4" ID to 7/8" OD. You can buy 3 of them on Amazon for $10.57 with prime 2-day delivery.
https://www.amazon.com/gp/product/B01G8X8284/ref=ppx_yo_dt_b_asin_title_o01__o00_s00?ie=UTF8&psc=1 (You only need one, but they come in a pack of three
)
Second, you need to drill out the bolt hole in your Clam auger shaft to 11/32 inch to accommodate the larger auger bolt used on gas auger bits (my auger bit is a strikemaster, you should verify the size of the bolt on your gas auger for this step
)
Once you have received your brass sleeves, simply mark the center of the sleeve and drill an 11/32*** hole through the center (both sides) to match the new hole in the Clam auger shaft.
My brass sleeve was a bit loose on the clam shaft, and a bit tight for the auger bit, so I simply cut a groove length-wise through the brass sleeve which allowed me to compress the sleeve slightly in my press and allowing it to slide smoothly over the Clam shaft, and slide smoothly into the strikemaster auger bit shank.
Simply line up the holes in all the pieces, install the retaining bolt, and you now have full use of you gas auger bits on your Clam auger adapter!
Note: The bearing sleeve takes up the room between the smaller Clam auger adapter shaft and your larger diameter "gas" auger bit shank. Because it does not change the length of the retaining bolt, you do not lose any strength at the joint. Because there was only 1/32 in difference in the bolt size from my strikemaster gas auger bolt and the original hole in the Clam auger shaft, there is absolutely no fear of snapping the solid steel Clam auger shaft by enlarging the hole 1/32". This also allows you to still use the strikemaster auger bits on your gas auger. If you want to also use a hand auger bit on your now-modified Clam auger adapter, you only need to enlarge the assembly hole to 11/32 inch*** on the hand auger bit (the size of the bolt on the gas auger bit) and get a larger linch pin or bolt for the hand auger!
