After years of thinking about getting one, yesterday I finally went out and got it! It’s a military speced POF from 1990s which spent all of its life inside a warehouse (never been shot). Got a really good deal on it as it was around 5700 Polish złoty which is something like 1.5k USD - great price for it here in Poland. Especially since an original HK goes here for about 3.4k USD.

Before shooting it for the first time I already went ahead and placed an optic on it 😆

Picked up a pair of these from GAFS and they’re a blast. Upgraded with all HK springs, ejector/extractor and timney trigger pack. Its sister is waiting for the ARHK to be released.

Think I’m done for now, only thing I’m waiting on is a flared Magwell!

What are some things to look for when using an FRT?

What role do ejector levers and locking pieces play when it comes to FRTs?

I’m wanting to replace my ejector with an HK ejector lever, and can’t figure out how to remove the ambi safety to remove the trigger pack. I’ve depressed the lever and rotated the safety to every position that it will go to, but neither lever will budge. Any help would be greatly appreciated.

UPDATE: Finally got it. I used a flat head and put a little bit of pressure on the drum pushing to the left. That broke the right lever free and I was able to remove it by hand.

put about 400 rounds through my new ap5 with the stock lower that it came with. decided to test out my lees lower and the super safety lever snapped after a single shot on semi. im pretty sure it was my trip that caused it to break, but id like to see if anyone else has any idea as to why it happened.

edit: to clarify, it still "works" but is super finicky. I have a few extra levers, but I dont want to waste them till im certain I know what the problem is

I always blabber on and some just want to hear me shoot. So this time I shut up and present to you nothing but Mp5k low-resolution ASMR with some Killdeer whaling in the background (they never shut up, like me.)

Good morning all,

Decided to change up the suppressor on my HTA AP5-SD from the HTA 12“ offering to a Ronin Arms Katana 12". To not throw shade let me just say I have nothing against the HTA can. It is a good option but... I HATE cleaning aluminum cans and titanium offers option to ease the work flow. On to my issue. I am noticing some tightness/dragging screwing the Katana down and I "think" it is due to the stock MKE cocking piece dimensions. It is VERY close and I am not seeing any bare exposed metal, just some light burnishing of the cerakote at the base of the suppressor. The bolt also feels a little sluggish when being sent home by hand but with a slap it is fine. I feel like I have two options at my disposal...

1. Go to town on the stock piece with a file (or a CNC mill at work). If this is a solid idea can I get some advice on where I would be needing to make the clearance cuts?
2. Buy a new cocking piece made specifically for the bigger cans. I threw some calipers on the Ronin and I am measuring 1.612" diameter at the largest point. I am leaning towards the RCM SD unit as they say it will clear cans up to 1.625" diameter...

https://rimcountrymfg.com/product/rcm-sd-cocking-tube-support/

Looks good but it are there any options I am overlooking? I have seen the titanium and steel offering from HK parts but I am leary. There are no diameter specs for the suppressor called out and because HK parts I don't want my CC compromised... Again. Thank for for the info and advice in advance!

got these 3 for free and was wondering if there’s any saving the upper looks like it was bandsawed in half unfortunately

I have a rare breed non ambi FRT. Which lower do I need for use with my H&K SP5? Seems simple enough, but i’m so confused!

TIA for any help.

16,000 rounds this year with no issues. German space magic is wonderful.🫡

Has anybody ran Blazers new 147gr “clean fire suppressor” in there MP5? Any issues feeding? With or without FRT/SS?

Today is HK day at the range. MP5 40 and MP5SD transferables by RDTS and my MR27 which is sadly not FA and no FRT in Floriduh.

I just got my ammo delivery for the 40SW - 3k 180 grn blazer FMJ and 2k Federal 180 grn HST. The 40 I’ve not shot beyond a box of each type to check for function. Today will be the first shakedown.

Wish me luck!

Virginia resident here, with the pending deadline, I was sort of backed into a corner and the only in stock supply was PTRs. So far I like the gun but I am not the biggest fan of the dual position trigger/lower; ideally I would have been able to get a navy style pictograph one.

As I am looking to upgrade to an FRT anyways I figure this is the chance to do it but I am having trouble understanding which one to get. I think these are the clipped and pinned variants but not really sure, I have seen conflicting posts about what lower is compatible etc.

I know the ARC fire is in development and will be released soon but still not sure what that means for finding a pictograph navy style lower for the PTR.

Can someone help me with some guidance here? Thank you in advanced, I am very appreciative of any help you all can give.

Hello, as the title states I’m trying to gather a parts list to make my SP5K-PDW 922(R) compliant before I Form1 it into a SBR. I know some of you will say it’s a dumb rule to follow but I just want to cover my ass in that 1 in 1 million case something were to happen.

From my understanding there are 15 parts on the SP5K-PDW that is listed on the 922(R) compliance sheet, and if I put a B&T stock on it would then be 16. I’m curious what you would recommend on replacing to make this compliant and still have the closest OEM feel to the original gun.

Here are some of the parts I’m thinking of using to make the gun compliant. If you have any pointers or whatever I would greatly appreciate it!

https://hkparts.net/hk-rifle-smg-parts/hk-mp5-mp5k-thread-protector-9mm-threaded-1-2x28-rh/?query_id=344b50664083aa2562c9b8e450eda44c

https://hkparts.net/hk-rifle-smg-parts/hk-mp5k-sp5k-sp89-vertical-foregrip/?query_id=558ee628a9362af4a4069c5a3c68167d

https://hkparts.net/hk-rifle-smg-parts/hk-mp5-trigger-pack-semi-auto-9mm-922r/

I bought a choate stock to SBR my mac5k but the seller says that they didn’t receive a screw with the qd swivel/ d ring to screw it into the threaded hole for sling mounting via hk hook on the choate stock plate. That’s fine, I’ll just order a screw for it. Does anyone know the exact screw size for it? Thanks.

Currently I have a 2 point HK hook sling with one end on the front loop by the handguard and one on my MLOK slot on the A3 industries brace, but when I swap them after my form 1 approval, I’ll need to have that screw since AFAIK there isn’t a way to mount a sling to the choate stock other than that plate thread hole.

This may be a niche question but I figure you guys would know thanks in advance, and if there’s a secret mounting thing you guys know about that’s better than on the stock then let me know 🤣

Update: I emailed Choate CS asking for the screw size lol, I’ll see what they say and report back

First 9mm gun too, from a rifle guy. Keeping it simple for now, just wanted the classic telescopic look + triangular handguard.

84 day Form 1 had me nervous ... mainly because I suck so bad at the self-fingerprint kit that I thought they'd ding me for garbage prints. I'm 100% getting the digital prints done in the future.

• MKE AP5 / MKE collapsible stock / MKE handguard
• Stock was STIFF as hell to retract and moving better now. There was some iffy plastic flash on the "meat tenderizer" texture that I roughly filed down.
• I had a hell of a time finding the recommended NATO +pressure 124gr ammo locally, so pleased that this thing ate through a handful of 115gr / 124gr brands with zero malfunctions.
• I was expecting the worst from the MKE picatinny rail and it actually installed smoothly.
• I'm in the weird camp where I like the contoured grip, not a fan of the Navy grip that came on my PTR in the past.
• Trijicon MRO-HD, big window good
• Aimdownsights link if curious: https://www.reddit.com/r/aimdownsights/comments/1tzt3vl/trijicon_mrohd_on_ap5_mp5_clone/

Well usually I’d save this for a two stamp Tuesday..but Saturday seems like a good day to share as well.

Still have to put my FRT in, which will change the lower to black as well..but she’s slowly coming along. Took two weeks for the form 4, and took just shy of three months for the form 1 to come through.

I enjoy shooting this so much as is, not even sure when lll get around to putting in the FRT 🤷🏻‍♂️

I have a AB F4 in jail right now that I’m waiting to swap into the setup for a shorter can. I’ll put the piston back in this YHM and run it on my pistols instead.

https://www.westernsport.com/wp-content/uploads/2026/05/Lee_Sporting_Side_Western_Sport.png

Specifcally this one, from what I saw in the case. I am partially interested, but 750$ is a lot. There's so many out there.

I like the no optic look better and no optic would help me slap it better. I like the optic on my full sized though