I had one of the original Remington 5mm's back in the day. I always liked it. I think there were several reasons it flopped back then. One, Remington had problems with the bolt design. There was too much of the case head unsupported and many of the rifles would blow cases with fair regularity. The other thing was, like a lot of Remington's ideas, the market wasn't ready for it at the time. In those days there just wasn't the interest in serious rimfire use. Most of the rifles available didn't have the accuracy to take advantage of the higher speed and flatter trajectory. People just didn't take rimfires seriously like they do now. Those that wanted something with more steam than a .22 LR were well served by the .22 magnum. I think that if the .17 HMR had been introduced in the early '70's it would have failed too. Cost was an issue as well. Like a lot of things, the numbers on the price tag were smaller than today, but the value of the dollar was a lot more. We were paying less than fifty cents for a gallon of gas. Figure what that almost five dollar box of 50 rimfires was worth in terms of gasoline, and ask if you'd be willing to spend the price of that many gallons of gas today on a box of them. I think that if a few manufacturers started making rifles at low, medium and premium price points, and if Hornady or one of the other biggies started producing ammo, the 5mm would take off today. I wish somebody would stick their neck out.