If you got that impression from anything I wrote, I certainly didn't intend to make THAT claim! Perhaps you're misireading earlier comments by others?
Actually it was something that occurred to me that might be the case based on the nature of physics as I know them. The momentum of the larger caliber .45 certain accounts for much of the felt recoil but physics being what they are a lighter bullet driven at a higher speed should have the same reaction as a heavier bullet driven at a slower speed. The thing is the .45 is said to have less pressure so I don't see how it can have more recoil to be dealt with. Yet I know it does from experience. I just don't know why and I haven't really heard a good explanation for why that's true.
But the 45ACP bullet has 39% more momentum.
Why is that true? The KE and the weight are obviously the reasons but I suppose what makes me wonder is that I haven't done these calculations in 40 years and the weight conversions make it difficult. I could spend a day figuring it out again or I could ask someone who knows. I put in my time explaining this stuff to others way back when but that's been many moons ago and a lot of my marbles are off their tracks now if you get my drift. I just didn't want to go through learning to do the equations again I suppose. They aren't all that hard if your brain hasn't grown lazy but my thinking has been about other subjects for a long time now. Yes I see the explanations here but I'd still like to see the actual math involved and I believe it's actually going to be pretty complicated so to heck with it. I'm gonna forget that I asked.
have never heard about other calibers and certainly not about a .45 version
Maybe the source I read on the subject was wrong but I thought they made a few in .45 ACP. I could be wrong again. Every source I've looked at today says it was only 9mm., .30 caliber and .22 caliber that made up the choices. I read the stuff about there being some .45 variants quite a while back and of course they could have been wrong about it. Probably was it seems. I'm having a bad thread it seems.