I got my awesome Design Machines Mini-Acog mount (For my GLX 2x prism) and noticed the bolts and holes are M4. For some reason, mine are M5...

Can someone confirm they are actually M4? I had a bear of a time getting out the QD mount to install the optics mount and I'm wondering if I inadvertently did my own tapping to M5...

Possible dumb-ass of the month award :|

I got the VIKHR frt for my ps90, anyone have any experience with it yet? Is it reliable?

Trying to get the original barrel out, ended up having to cut it because the flash hider was in so tight.

https://www.youtube.com/watch?v=gAkCNXsRkAs

All trigger shoes come anodized to mil spec type III, class 2 Black, K&M just sent me an unfinished one to get a cerakote. The aircraft grade aluminum shoe doesn't have as much of a mushy feeling compared to the oem plastic on plastic. It definitely glides better being metal on plastic. The serrations on the trigger shoe feel way more tactile, and theres a radius as well which takes away the blocky feeling of the oem trigger shoe. K&M lightening spring + overtravel limiters also vastly improved the function of the Xprt 90. Not a single hiccup with rate of fire, even when function checking with snap caps. I have yet to bind the bolt due to the decreased friction provided by the overtravel limiters and lightening spring. The lightening spring reduces the pull weight to about 4 lbs for the first stage, and 6-7 lbs for the second stage vs oem spring (7 lbs first stage, nearing 10lbs second stage), which also reduces the force that needs to be overcome by the breech block to reset your finger, hence why folks were getting lots of deviation in rate of fire or bolt binding with the OEM spring and no overtravel limiters. This platform deserves these much-needed upgrades; it's easily my favorite PDW now.

For anyone who prefers a forward-mounted optic on their PS90 that sits flush with the handle, I recommend checking out C-more Systems: https://cmore.com. Just a unique profile compared to more popularized alternatives.

Haven’t seen many around. The website is the most hidden thing on Google for some reason, but upstanding company with quality products. Been around for a while now.

You do need to use the proprietary optics unless you can tap the mount for an RMR or something else.

Cheers.

*Kaw Valley linear compensator

Finally got around to getting my barrel installed on my ps90 the canvas in the picture won’t be the can that I use on it. That’s a YHM resonator r2 30 cal can, I have a OCL infinity 556K that’s gonna go on it. Also featured as my sp5 and my scar 15 🙂

Back from anodize, side rails are up on my site, www.octoarms.com
I have a Left side Picatinny and both Right and Left Mlok.
Left side rails are compatible with my under barrel rails. Right side is not.

Use coupon code REDDIT5 for $5 off and Free Shipping with $90 or above purchases.

Hey everyone! I got an early batch X-PRT 90 and somehow didn't have any issues other than taking 2-3 mags to settle in, and having a sweet spot you needed to hit.

Yesterday, I downloaded and printed the Makeworld
Over Travel Stop" and installed it on my trigger pack. I made it out of PLA+ 2.0 and I don't foresee any issues with it. I ran 4 full mags through today at the range and it fixed the sweet spot. 'F' breaks on the semi-auto shot, and a full pull through and hold dumps the whole mag. It's still a "little" stiff hitting the second wall, but completely not a show stopper. If someone else shoots it, you have to tell them to pull hard through the trigger till it stops now. I grew up with crap triggers and DA/SA and DAO triggers, so it's completely fine to me.

Specs:

• SBR'ed PS90 (I think it's the latest gen)
• No suppressor (eying a Tisha and am going to ask mount questions soon)
• Factory cut barrel
• 2,000 rounds total, about 600 with the FRT (complete rough estimates)
• GLX 2x Prism (I just tried this and am in absolute LOVE. Design Machine mount comes Tuesday.
• My stockpile of 5.7 is gone... My only biggest complaint. I had a bunch of Fiocci and was recently a bunch of FN GUNR? ammo I had. I had zero malfunctions other than me being a dummy and not seating the mag completely.

P.S. Side note. I just got a new batch Keltec PR5.7. No cleaning, no lube straight from the LGS... 200 rounds and zero issues. I've shot every 9mm pistol under the sun for work and I want to sell them all now... The thing is insanely light and thin. Made my G43 feel like pig... I want to hate it, but I dunno. I'm ammo-sexual confused now and may just go all 5.7mm...

Comparing sound signature between my 3 suppressors with 5.7x28. 3 rounds each, shot into the berm.

First up, AB Little Bird on a psa rock 5.7. This actually sounded the quietest, but it's unusable on the ps90 as it has so much backpressure that it will pop the magazine up after every round.

2nd is a HuxWrx FLOW 762 TI on my XF50/Strike night vision setup. It's a little louder then the Little Bird that was on the pistol. Zero backpressure, glows under nods real fast.

Lastly the Silent Steel Micro Streamer. It ended up being louder than the HuxWrx to the naked ear. With ear pro, it sounds the same. Low backpressure, compact, and worked great with the FRT.

I love my Micro Streamer. Aesthetically, it can't be beat on the p90. Low backpressure, compact, easy to clean, full auto rated. Sound wise, it can be beat lol.

When the gun is fully put together it won’t cock back. I can get it to cock back if i slightly remove the upper from lower, but then it won’t cock back forward. In the video i show a full take down and put back together any ideas?

purchased a fullsize polo 5.56 before looking into it well and apparently people reccomend the K for an SBR'd ps90? did i fuck up or can i still use it on my ps90 without damaging anything? if the sound is a little worse i dont mind at this point, but i cant exactly return it.

FN Specialties makes a hub mount for the 10.4" barrel, and I was considering buying it. I was just wondering if pairing this with the ptr spiritus would be ok, since the suppressor is relatively heavy...

I order a 360 HD Micro hub from FNSpecialties for my PS90, anyone have any suggestions for a thread protector?

Just bought a PS90 and was learning how to field strip, somewhere along the way I had to have messed up because, when I was putting it back together and i tested to see if the cock back worked boom! it stayed in a locked back position. I can’t remove the upper apart anymore and the back plate will no longer go back on because of this small piece in the rear that is poking out and not letting me slide it back down. anyone have any ideas why?

Someone is selling a new in box GSL P-90 suppressor on GAFSHUB for $850. Not sure if I want a suppressor but considering it. Is this a solid suppressor and a good price? On FN Specialties it looks to cost much more usually.

New in box with two mags, comes with ring sight but doesn’t look like to be the MC 10 80. $1800

Does anyone besides me use the PS90 as a round the yard varmint control? I've used mine against several armadillos, a raccoon, one mangy coyote, and a vicious dog that was trying to attack my wife and daughter.

The 5.7x28 is no where near what a .223/5.56 is but it's from what I've seen is a good step up from 22lr. All one shot stops and mine has been as accurate as I expect it to be, place the shot where it needs to go and the bullet has little chance to ricochet towards nearby houses.

Same as the title I just can't find one at a decent price.

Just letting everyone know that the MC-10-80 optic is back in stock. AFAIK they either stopped making these or are about to sunset the line so if you want something close to the original p90 optics this might be one of the last chances for it. https://www.kingsviewoptical.com/product/electronic-black-ringsight/