The ammo that made the 5.7's reputation are the 27 gr., non-expanding hollow points. They run about 2100 fps. out of a 5 inch gun. The 40 gr. Hornady V-Max stuff runs about 1740 fps. out of my gun.
All you need to do is shoot the 5 inch FN against a 5.5 inch Ruger in .22 Magnum Rimfire with 40 gr. ammo in each. The results are dramatic. Against a one gallon jug of water, the .22 rimfire mag. expands and penetrates, but does not swell the jug much. The 5.7 with the V-Max load blows the front half of the jug apart. The bullet fragments will be found at the back of the jug.
The 27 gr. loads are the kevlar penetrators. That bullet stays in one piece, but it tumbles after entering the jug. It also blows the front half of the jug apart. E
Agreed that the apples to oranges comparison of a 22 magnum rifle being almost as fast as a 5” barreled 5.7x28 chambered pistol makes no sense.
How is it nonsensical? The Hornady 40gr. V Max is traveling 1740fps out of your pistol, correct? Stated, published velocity of the 40gr. WMR is 1875fps, so how is that NOT comparable? Bullet differences aside, if anything, the ballistics of a WMR rifle are better than the 5.7x28. I fail to see how that "makes no sense". The numbers ain't lyin'.
Lies, damned lies, and statistics.
5.7x28mm ammo is proprietary to FN. it’s known that most (not all) is contractually down loaded to avoid the armor piercing stigma. More to the point you’re comparing a rifle length 22” barrel to a 5” pistol length barrel. A .308 Win with a 22” barrel will look a lot better than a standard 300 Win mag round much less a downloaded 300 Win mag round out of a pistol length 5” barrel. It’s absolutely apples to oranges and nonsensical.
For any kind of meaningful comparison you need to standardize on a barrel length for comparison and loaded to SAMI specs ammo. For a 5.7x28mm round chambered in a FN 57 with a 5” barrel which is suboptimal compared to the 10.5” P90 that it was built around you may as well be comparing a 308 Win with a 22” barrel to that 300 Win mag with a 5” or 10” barrel it’s the same thing. Slanted numbers.
To beat a dead horse. A 22 WMR has about twice the effective range as a 22 lr but if you compare the 22 lr chambered in a rifle with a 20” barrel to a 22 WMR chambered in a pistol with a 5” barrel they’re effectively the same because you tilted the scale and are giving up about 1000 fps when you chop the barrel of the WMR from 20” to 5”.
There aren’t many chamberings out there of similar bore diameter that given the several times longer barrel from 5” to 20” that won’t outrun the other. Yet 5.7x28 with a 5” barrel loaded to max SAMI specs and with a 5” barrel still outruns a WMR loaded to SAMI specs with a 20” barrel. If anything that’s an absolute exception to the rule.
