I finally had my OEM barrel cut and threaded by Taylor so I could do a better comparison against the CMMG and Shaw barrels I have.

Note that the cut barrel is slightly longer (like 0.4") than the CMMG/Shaw and I found that the crown wasn't as pronounced as the CMMG/Shaw/typical factory barrels - but I could still see the angled chamfer for the crown using a borescope and everything looked clean). Alignment rod showed dead-center with the B&T P90 suppressor.

Ammo used was AE 40gr, Fiocchi 35gr, Fiocchi 40gr, Fiocchi 62gr, SS195 (old school stuff that is hot), and SS195 (newer 2021 lot which is slower). Same as before.

Right away I could tell a difference in POI shift with the suppressor, as well as the average group sizes.

The CMMG would group 0.5" 5-shots at 25 yd same as the Shaw. The OE cut/threaded barrel couldn't beat 0.75" at the same distance.

With the B&T can, I'd see 1.5" POI shift down with the CMMG and only 1" POI shift down with the Shaw. With the OE barrel, it was 2.5"

I also noticed the cartridges were generally 40-100 ft/s slower out of the OE barrel than with the Shaw or CMMG.

The extracted cases looked fine from the OE barrel, about 10% of them would have a cut on the area near the neck. The Shaw would show nasty scuff marks but still zero issues shooting AE 40gr suppressed with either the Shaw or OE cut/threaded barrel. With the CMMG, I'd see several misfeeds per mag while suppressed (no issues unsuppressed).

The Shaw has the tightest chamber at 0.314", followed by CMMG at 0.315" and the OE barrel at 0.317"

The Groove ID of the OE barrel was 0.220", while the CMMG was .2260" and the Shaw was 0.2215". The Land ID were about the same, all 0.219" (Shaw was 0.220").

Only recent change is an FRT, and a swap to a slightly less bulky muzzle device. (Doesn't matter when the suppressor is on but it fits in my backpack easier)

Just figured I owed it to the group because of everyone's help and just in case someone else has similar issues.

I checked the chamber spec as suggested, seemed good on the cmg barrel. Disassembled, Cleaned and relubed everything as suggested. Got different ammo to try as well.

Took the girl out to the range today. Ran fn blue tip. Ran 3 separate mags with varying amounts loaded in them (5 rounds, 14 rounds, and 31 rounds) ..... no jams or failuire to feeds. Cases had very minor scraps nothing like before. Barely even noticeable.

Then ran the same mags with varying amounts loaded in them of the orginal Fiocchi range dynamics half 62 grain and half 40grain. And boom back to jam city population me. Most had scrap damage like before and a few were smashed in like others posted. Two so bad the bullet was knocked completely out. Got runs of maybe 3 to 4 in a row at best before an issue arose.

So I guess at this point in the guns life i am going to chalk it up to that this gun doesn't like range dynamics 62 or 40 grain? Ill try other types as i burn through what I have and the gun gets more seated in. Total round count now is about 300 rounds.

Thanks for coming to my very scientific psa 😆

New to all of this but glad I joined up! Always wanted a p90 and ive had a ps90 for a couple of years now. I'm glad I found this because ive already learned some stuff I didnt even realise I didnt know. Here's what my previous setup looked like followed by my now current one. The next step I want to take is to sbr it. I was wanting to put a cmmg barrel on it and use my dead air sierra 5 to suppress it but after reading several posts here I think I'll be going with a shaw barrel. I also was wanting to frt it with the xprt90 but I think now I'll try the wd90. Thanks all for the info so far and looking forward to bring part of this community and finding my people 😆

submitted may 3rd got approved at 8:33 this morning so a 77 day wait. times might be coming back down or my background check didn’t get held up.

Browsing AmmoSeek for fun. It seems like the cheapest (cost per round) listings are now SS197SR. Those positions were usually held by Fiocchi Range Dynamics or Federal.

I know one can probably find retailers with better prices than those listed on AmmoSeek, but I figured AmmoSeek is large enough to reflect the average market price.

Is the current SS197SR price considered good?

Honestly, doesn’t seem like a horrible deal for an extra 50 round mag and a optic

Edit: this is including a optic and an extra 50 round mag

Edit: i’m not coping anymore. I low-key overpaid

Does anybody have any clue as to when some of the major retailers will be restocking? It’s my understanding that FN restocks in batches

Edit: the gun

Not sure what took me so long, but I finally got one. Don't even have ammo for it right now, and I'm not sure I even want to shoot it until it's restored to its proper form.
Plan:
- Drop the Picatinny rail --> ACRO mount inbound.
- SBR
- Mag conversion 30 --> 50
- Suppress (cant decide HUXWRX vs Tisha)
- Sling
- FRT BRRRRT
- Die happier than before having this

Also... for under $150, that little Burris sight is all right. Hard to knock it when the competition is $600ish.
Am I missing anything?
Hit me up with your recommendations in the comments!

HB Industries hammer with 3D printed lever and selector.

Details: Just sbr'd, cmg barrel, (yes barrel spring is in lol), no obstruction in barrel, true new fn mags, New prodution Fiocchi ammo, have not tried fn ammo yet but have some on order. Unfortunately it was not shot before I sbrd it so not sure if that could be the issue.

Won't consistently feed rounds. Seems to feed a round or two fine, then some will half seat into chamber. Tried multiple mags loaded between 5 rounds to 25 rounds. Best consecutive round count was 5 or 6 before a jam.

Ejected rounds look like this. Seems to be case scraping the bottom of the barrel? Not sure whats leaving the marks otherwise. Not all rounds are scrapped but id say 85% are. Also had some rounds where the bullet was smashed into the case.

Anyone have any ideas? Any help would be much appreciated as I was sooo pumped to finally join the family but kinda pissed atm.

Since i was so frustrated i did order aluminum mag followers and stronger springs to try too, before I even left the range.

4.25 inches long, 5.56, low back pressure, od green to match the stock. Will compare it to the HuxWrx FLOW 762 TI and AB Little Bird.

Image 1. The part of a case that was slightly stuck in my chamber.

Image 2. The case segment in the chamber.

Image 3. Chamber after removal of the case segment.

Image 4. Chamber after cleaning.

new 10.5in cmmg barrel with only a few 100 rounds through it.

The ammo that this occurred with was FN SS197SR.

Is this more likely to be a problem with the barrel or with the ammo????????

I have a PS90 I bought last year. I'm thinking about SBR'ing it and wanted to know what other parts I need. I already bought a shaw barrel. What other parts do I need to complete the process

I plan to reload like I do for other calibers, but don’t like the floppy sack catch. This guy clicks in, I have 47 full rounds in there, so it should be enough for 50 spent. I may make it more rounded to match a little better, but I’m happy with V1.

Now that my Form 1 is done I’m ready to submit my form 4 for the suppressor. My setup will be SBR with the XPRT-90 frt mod.

I went to 3 different LGS earlier and they all had 22 caliber suppressors that would be compatible but only one had a suppressor that would work with the frt mod and not erode. It was a huxwrx and they wanted 350 for it.

I want to make sure the suppressor I get has low blowback and will take the beating the xprt-90 will put it through.

I want to stay in the 500 range but the 556 suppressors I’ve been looking at like the silencerco. And huxwrx are around 1k. If the juice is worth the squeeze. I’ll bite the bullet no pun intended.

Just under 3 months For my approval. Digital fingerprints. I was waiting for that denied email and figure out what I did wrong but it looks like it was a one and done.

Now to hit up the gent on here that does SBR conversions. Also I’m surprised my SBR approval came before my XPRT90 frt.

New to the group bad pic but here’s my PS90 set up for hunting with a Sig Romeo w/ magnifier and a green light mounted to the side. Would love to talk about FRT sbr and supressor recommendations if anyone has some tips or tricks. Would really appreciate it !!!

Took these pics a while ago and forgot I meant to post them here sharing the results of my bag hunt.

I wanted a bag to overly big but also not be that screamed there’s a gun in here. Picked up a Discrete Covert Ops bag from Elite Survival Systems bag. I went with the 22”, meant for the MP-5A3.

I have about half an inch on either side with my PS90 stored. I’m running the GSL bi-lock muzzle device, no thread adapter. YMMV front of the stock to edge of the bag there’s a just over 3”.

The included mag pouch didn’t fit PS90 mags, but the bag is partially Velcro lined and Savior extended mag pouches fit perfect.

Only used it once but it seems like decent build quality. The bottom has three rows to strap things down. I used the middle and strapped a suppressor to the top row. The fix rows have Velcro on the inside so when you run one of the included straps through it won’t slide around.

No pics of it, but there’s a front zippered pouch. It’s jut an open space. Would’ve been killer if it was Velcro lined or something but it’s big enough to still be useful.

Also fits my DDM4 PDW quite nicely.

Walking out of the engraver’s shop and realizing the PS90 would fit in a rifle bag half-as-long as the one it was currently in.

Any ideas? What are y’all using.

Tried my laptop bag but it’s 2” too small.

Od green tri-rail that is waiting on its dedicated suppressor, XF50/Strike night vision setup with HuxWrx FLOW 762 ti, and classic USG with ringsight and white light.

Converted my new ps90 to an sbr. Ran a standard suppressor, an ocl ti 22. Mounted a holosun thermal red dot for some night time hog and coyote action. But the First 5 rounds had the carbon from the gasses gunked up on the bolt face so bad it would not return to battery. This happened several times and i did not even finish a single mag of ammo suppressed it was dissapointing. It was the 27 gr fn load and a handful of subsonics if that makes a difference. Unsuppressed no issues obviously. I take it ill need a flow through suppressor to avoid this? Thanks.

Giving XPRT my money in advance and not receiving a product for months seemed crazy to me so went with ratlr r.

Instal was easy peasy. 3 position safety works great as well. It’s very interesting how this thing works.

Took a few mags to get the hang of finding the sweet spot in the trigger (or break it in idk). Couldn’t get more than a 3 rd burst first mag then progressed into longer bursts. May been my finger may have been it breaking in time will tell.

I give it a 10/10 for fun. And a 10/10 for shipping right away!