5.7 upper...they any good?

[luv2pbal]

just saw one on a site for $699....uses the FN horizontal 50rd mags and ejects the round through the magwell. says it doesnt uses gas so it also keeps bolt clean. anyone have any experience with one?

[Dave L.]

I bought a PS90 for fun...I would never buy an AR upper that shoots 5.7. It just doesn't make sense. Same diameter round, less power, same price as 5.56, extremely limited availability of ammo...the list goes on.
I have no clue on the reliability or quality of this upper though.

[Parabellum9x19mm]

+1, i also have a PS90 as a recreational blaster and i don't think i'd buy one of these uppers.

[MadDog]

I got an AR57 upper because I have a Five-seveN pistol and wanted a long gun to match. I tried the PS90 a number of different times and would not get one as they are too small and feel very crampt as I am a big guy. To not get a 5.7 upper because the round is not as effective as the 5.56 is pretty silly. I like variety and have AR uppers in a number of different calibers. Some of you say you have PS90 as recreational blasters. Since when does an AR "have" to be a serious tool and not a recreational blaster? I am left handed and find most suppressed uppers to be a pain to shoot as blow-back from the ejection port is pretty substantial (especially with Gas Buster CH's). The 5.7 was made to suppress as what little gas you do get goes right down the mag well. Mine is out right now having 2" taken off the front of the handguard as I didn't like the slanted look and wanted the front squared off. I am also having the barrel cut down to 10" so with my suppressor the overall bbl. length will be 15.5" If you are worried about ballistics, Elite Ammunition makes some 5.7 ammo that puts out 2,800 fps and 350 ft/lbs. Not bad for a "puny" innefective round. They also make sub-sonic ammo that will actually cycle semi auto. Try that with an 5.56 in your AR. As soon as it comes back I will post pics.

MadDog

[Parabellum9x19mm]

if you like it, more power to you. i can't own suppressors in my state, sadly...so that part doesn't really factor into the equation for me.

interested in the Elite 5.7x28....too bad all the tasty ammo is out of stock. i have a bit of brass tho, nice that they will reload with customer supplied brass. hopefully they'll get more bullets soon and i'll be able to try it out.

how much is it for 50 rounds of penetrator or personal defense ammo? how much of it have you shot? does it chrono at a consistent velocity?

[CatmostFeared]

I shot mine yesterday and love it.