AR57 Pistol: A short review & praises for Magpul MBUS sights

[LisaA]

Hehehe...you know that you're welcome to try out any of them anytime Lisa.

Al

PM on the way!

[J Star]

Nice pistol!

FYI, the PS90 does not damage the spent casings. Every round I have shot through mine has ejected an undamaged casing. Some of the older PS90s actually seem to get dinged up inside the ejection port by the casing. In the AR57, the casing might be hitting the magwell at a funny angle hard enough to damage the casing. I don't know, never gotten to play with one.

[mythaeus]

Nice pistol!

FYI, the PS90 does not damage the spent casings. Every round I have shot through mine has ejected an undamaged casing. Some of the older PS90s actually seem to get dinged up inside the ejection port by the casing. In the AR57, the casing might be hitting the magwell at a funny angle hard enough to damage the casing. I don't know, never gotten to play with one.

Thanks for the info! I don't think it's the mag well as every case is dented the same way with or without the "brass catcher" mag inserted. I think it maybe the bolt/extractor design, but I'm not sure either.

Al

[Asmodeus6]

I wonder if the extractor is bumping the case out and causing it to twirl into another surface. Like end over end with enough force to cause the case deformation.

I've never so much as looked at the AR57 setup closely so I am just guessing.

Perhaps the bolt flings it downward end over end and it's left to twirl there just long enough to get smacked with the bolt coming back forward with the new round?

It would suck if you end up with bags of damaged brass and there isn't anything you can do about it...

[photoshooter]

Looks great Al! I was over at the range a few times this week, sorry I missed you. Looks like you've got several new tools since I last saw you.

[mythaeus]

Looks great Al! I was over at the range a few times this week, sorry I missed you. Looks like you've got several new tools since I last saw you.

Thanks Mike! I've gotta keep myself a few step in front because you're like the Speedy Gonzalez of gun purchases

Al

[d90king]

After doing some research on the PS90 and kept an eye on the market for PS90-related stuff, I found a gentleman in Idaho selling 4 PS90 mags and 850 rounds of 5.7x28mm for $400! At about the same time, someone on ARF.com was selling a new AR57 pistol/SBR upper for about $100 less than any retailer online. Having 2 complete RRA pistol lowers sitting around naked, I sold one and proceeded with the AR57 purchases. I soon realized that the upper doesn't some with any sights, with great curiosity of the new MBUS, I found a good deal on the pair for $80/shipped.

Got the upper in the mail, installed the sights, slapped in onto the RRA pistol lower and headed to the range yesterday. Wooooow...I was thoroughly impressed. The complete gun was light weight, recoil was minimal, and it's extremely accurate. Unfortunately, my range doesn't go any further than 50' so I'll have to wait to hit an outdoor range for better assessment. My wife and I shot 100 rounds through and had 2 jams earlier on. The bolt was dry so I oiled it up a little and the rest ran perfectly fine.

If you're not familiar with the AR57, it's an upper variant that takes PS90 magazines and uses standard AR15 lowers. The mag is loaded on top of the upper receiver and the spent casings are dropped down through the lower's mag well. I use a gutted Lancer 30-rd clear mag as a brass catcher. The mag holds all of the 50 spent casings. For now, I have to hold it in place with my weak hand, but I'll be cutting off the protruding part of the mag so that it will lock in place (the AR57 upper bolt fits flush with the top of the lower so standard AR mag won't go all the way in). One thing though, the opening end of the casings gets dented pretty good. All of the shell are squared off on one edge. I'm not sure if that is the case for PS90 as well or just the AR57 upper.

I was as impressed with the MBUS sights as I was with the AR57. I don't care for the way they look on the upper, sort of curved and unflushed, which breaks the aesthetic lines (IMHO) of the gun. However, the sight picture is great and targets are easier to acquired compared to the Matech and other A2 style sights I have on my other guns. I think the fact that the width of the sights are wider makes it easier to find center (not sure if that makes any sense). What I mean is that with the skinny Matech, you only have 1 point of reference to align your eyes. The left edge, right edge, and peep hole creates a 3 points of reference making it easier for the brain to find the alignment point better. OK, maybe it was just in my head, I don't know. Anyway, now I'm thinking of getting a few more sets to replace my other sights.

Oh, one minor thing. I replaced the standard grip with a Magpul MOE grips. Nothing to write home about, but it worth noting that the grip was comfortable, fit both of our hands well, and not having the standard AR15 grip's bump is a nice feel.

Here are a few shots of this fine baby:









Al

Very cool rig! Thank God that AR's need a buffer.... It would be great if you could do that with AK's... Nice job, looks like a great project that ended well. Hows ammo cost for that baby?

[mythaeus]

Very cool rig! Thank God that AR's need a buffer.... It would be great if you could do that with AK's... Nice job, looks like a great project that ended well. Hows ammo cost for that baby?

Thank you my friend. I cheated and didn't build it per se. Got the lower complete and upper too. Just need to mod the "brass catcher". Hey, I'm allowed to cheat after 3 complete builds on my own

Actually, ammo is priced similarly to .223 brass, if not slightly cheaper. A box of 50 costs $19.99, but sometimes on sale for $16.99. Compare that to $8 - 8.50 a box of 20 of .223.

Al

[smoke-wagon]

looks awesome al, we definately have to get together again. i haven't been to the range much since i bought my house so i'm itching to let some brass fly, plus i still have all the .223 saved from the last time we were supposed to meet . let me know when your free buddy.

[mythaeus]

looks awesome al, we definately have to get together again. i haven't been to the range much since i bought my house so i'm itching to let some brass fly, plus i still have all the .223 saved from the last time we were supposed to meet . let me know when your free buddy.

The house is the right priority for sure bro. We'll be at SPAG Wednesday night if you wanna come out. I have a few .223 you can send your boxes down range. If not Wednesday, maybe we can set up a time for next week.

Al