My cuz has one. I call it a 6.5-06 AI, which really gets his goat. He absolutely insists that it’s a 6.5-280AI, which of course it is.

ML Knowlton was building 6.5-06's almost 50 years ago, he built my 6.5-284 just over 40 years ago. 2 years later he built me a 25-284.

Dale Wise built me a 6.5 Gibbs about 25 years ago. The Gibbs is based off of a 06 case and with fire forming the shoulder is moved forward along with being sharper adding case capacity. It's has a bit more than the Ackley's too.
I havent shot in in many years but looking at my notes was getting 3200fps+ with 140's in the Krieger barrel.

Nothing is new anymore, most wildcatter in the 30,40,50's been there an done that.

I am still curious why the 6.5-06 hasn't become a commercial success.

Used to be, Americans tended to shy away from anything metric. The 7mm Rem Mag got that stigma to not hold up for a change

Had they called it a 260-06, or 264-06 it may have done better. Even though they would all be the exact same cartridge.

284 Winchester could be called a 7 Winchester or 7mm Winchester. They were smart enough to call it 284, though.

Fireman,
But wasn't the 284 a flop (at least currently very little factory ammo).

I find it interesting why/how some cartridges are a smashing success and others are duds. I think sometimes the stars simply align.

I do not know if it was a flop. It may have been more popular for competitive shooters, rather than hunters. Or the 7 Rem Mag eclipsed it. I have not read the history of it in a few years.

Maybe there were so many civilian and military rifles chambered in .30-06, everyone just ran what they knew when it came to hunting.

I mostly hunt, don't have much opportunity to shoot long range targets and 100 yard targets are, well, just 100 yard targets....
Until 5 or 6 years ago about everyone I know that hunts owned either a 30-06, 270, 7 mag, 30-30 or a few had a 243. I was one of the few that had a second rifle, 338 Win Mag, for bear hunting. Now they have all expanded their collections to many different calibers. I put up the 30-06 that I have hunted with for over 40 years and now shoot a 25-06 and it is great! I just got a 6.5 Creedmoor and may be switching to it soon.
So I think most were 1 or 2 rifle owners for a long time and never saw a reason to switch until recently with the advances in components.

I think most of it had to do with the actions it was originally designed for, Model 88 and 100 Winchesters. Factory ammo had the bullet seated so deep the extra case capacity was a waste. The 7 mag being introduced a year earlier certainly didn't help.

This^