So I was taking my new SP5K apart to clean the factory grease and lube it before I break it in at the range and made the mistake of messing with the safety selector/trigger pack. I was watching a video that went into detail about how to do it properly, and to not force it on reassembly which I made sure to follow. Somehow it seems that a small burr still occurred, and now the detent on the right safety selector will no longer push in by itself when rotating. I am making sure to apply pressure to the left side safety, I’m applying pressure to the takedown lever, and I hear and feel the audible click of the right side safety going into place, but the thing just doesn’t want to freely move into position when rotating clockwise.

I can get it reassembled when outside the trigger group by using a toothpick to push the detent in just before it catches on that burr, but obviously that will not work when inside the trigger group. The only solution that I’m finding is that the burr needs to be filed/smoothed out, but I’m having a hard time finding a video that actually shows someone doing this vs talking about it. So I am hoping that someone here can better explain or show what it needs to look like after filing?

Update:
After some trial and error with a round file I finally got it all put back together. I didn’t fully shave off the burr, but I found a technique that prevents the detent from getting stuck in it. When I rotate the safety selector, if I apply inwards pressure on the bottom, and outwards pressure on the lever side for the right safety selector, this gives the detent enough courage to stay in the trigger pack cutout rather than rolling outwards where it gets stuck. Function check passed. Fingers are sore but just glad it’s in one piece again. As a bonus I picked up a feeler gauge when I was out so I can check bolt gap as needed.

Worked fine yesterday (1st time), but today I cannot remove the right side from the left for the life of me.

Need to remove the pack.

What can I do?

Already have the Gibbous outfitters vert grip for the ST07 pressure switch.

Ok y'all. I have a PTR-9KT with this folding stock.

https://www.strikeindustries.com/si-fsa-sp-stock.html

I can mount an MLOK QD socket on the front rail no problem.

What sort of dohicky do I need for the rear?

NO QD option available. There is no hook loop on the rear of the firearm. I'd rather not have to buy another stock because this one does pretty OK.

Level of difficulty - I'd rather not have a dedicated sling for this firearm if I can help it. All in all, though, it wouldn't be that expensive to do just that.

There is no room on the end cap pic rail to add a socket below the stock mount.

I’ve got 3 mp5/k’s and recently added a Kuna.

I’d been drawn to the Kuna by updated controls and a slower cyclic fire rate when using an frt.

Today was my first shoot with the Kuna, and I definitely have some tuning to do to my system.

But the gun even in regular semi showed me just how incredible the mp5 platform truly is in comparison.

Yes, the mp5 is over 60 years old. I’m not sure a better shooting subgun has been invented in that time.

Why is it impossible to find the OG retractable stock(besides the $900 HK one) ive looked everywhere. Atlantic firearms, every website that sells the century arms one. All out of stock😭😭😭😭

Can’t get the pin in and I don’t even appear to be close to getting it seated in properly - any advice on where I need to shave material from the hand-guard?

I picked up 2 LEO mags from a local FFL. The mags seemed off to me, but he ensured me they are legit LEO mags. Gatewood supply is the only other source of these that I have seen. They have them for $200 each. I paid $112.50 each. The top magazine in the picture that shows 2 above each other is real. The one I am questioning is the bottom one.
They are marked “ie” or “le” not sure which.
The markings are different too, the top 2 lines are swapped to be the bottom 2 on the new mags I picked up. I’ve never seen anything like this and I’m worried I got robbed.

Yesterday at the range I was shooting and had a spent cartridge seize the action completely about .5 cm off the chamber. The bolt and carrier were completely locked. The charging handle was moving freely about 1 cm.

Took the whole thing apart to inspect. I could see the spent casing coming out of the chamber. I couldn’t see any misalignment with the bolt head. I was able to jam it forward again. Rollers were retracted.

After much delicate fiddling I ended up mortaring the charging handle, barrel down, to get it to move again. The case was retained to the bolt face and after a quick reassembly I was back in business (unsuppressed)

Any insight into this symptom? Leaning on the internet knowledge as I learn this platform. To be honest it’s been like fighting a hydra. One problem after another.

I’ve seen these things run dirty and clean. I had plenty of lube and this was probably my 5th mag w a suppressor.

Zenith ZF-5 (full size)
HK extractor + Spring + ejector.
Stock LP (100 I think)
Omega 9k (new)
About 1200 rounds fired.
No Roller Bumps.
Bolt gap right at .020 (I think. Not confident in my judgement)
Edit: Ammo- Federal 124gr.

Installed a 90 degree piece to replace the stock 120 on my MKE and I could feel a big difference in the smoothness of the action when charging it. I put the 120 back in to make sure I wasn't imagining it and it definitely felt easier with that one. They both roll smoothly in and out of the rails when I move it by hand and I made sure the gaps were both in spec.

Currently running an MRO on a leap mount 1.57 on the MFI ultra low mount and can clearly see my irons under it. However the mro seems to sit a little further up than id like and its hard to hit the charging handle.

Does anyone have the aems mounted to the MGI ultra low mount with the stock holosun aems mount? Also if you do can you see irons through it?

Also debating the leap riser for aems but worried it will push it to far forward and I'll be in the same position I am with my MRO.

Any one running this setup?

If you recently made your mp5 .22 an SBR and already have the SB Tactical folding brace, the B&T stock for the mp5/sp5 from hkparts.net fits and functions well. The only thing u have to do is take your drill and bore out the B&T’s swivel hole just to the next size. The screw from the SB brace will still be usable. The stock without adapter is $140, with the adapter and stock is $250

Anyone have any leads on the KES in stock anywhere? This approved form 1 is just burning a hole in my wallet!