u/GassyNizz

Welp, today was an absolutely glorious shoot with my 3 mp5’s.

Last time out I used the ASD trigger and hammer for my full-sized mp5 after the hammer unjammer failed me in the rain. With JP rifles 3.5 pound springs, the ASD fcg is incredible. But be sure to use screw-in style anti-walk pins; standard fair won’t cut it!

The mp5k’s run great with their Geissele triggers.

CAT Mob’s on the K’s; Milkman on the full-sized. RU3’s for the tri-lug cans.

90 lp’s in the MAC5K and full-sized; 80 in the Zenith K.

And the 5.56 gun I left in this edit shoots softer than any of the soft-shooting mp5’s!!

And oh, Blazer Suppressor 147 is as gtg as it gets!

Also my daughter, on the left.

Needless to say, I’m over the moon!!!

This is Grace’s 4th year in drum corps and first year with the Boston Crusaders.

She tells me it’s an unbelievably wonderful awesome experience. There is such positivity in the corps from membership and staff.

The knowledge, abilities, capability, and tremendous work effort from the students and the instructors allow them to accomplish amazing feats in a tremendously positive and uplifting environment.

I’m SOOOO excited for what Boston has to offer this year.

WE LOVE YOU GRACE!!!!

When your daughter is a Boston Crusaders lead trumpet and you can FINALLY show the world!!

We Love You GRACE!!!!

What a great shoot today.

Sadly, last time out I discovered the printed materials of both the hammer unjammer and the full-sized buffer can fail in the rain.

So today I used both ASD ARC trigger and their special rounded hammer in my full-sized ZF 5. The ASD fcg was paired with a JP Rifles enhanced reliability spring set.

Woah - this dropped the ROF 50 to 100 rpm compared to my G$ fcg’s. And with those springs and polishing, this new ASD ‘mil spec’ group is 90 to 95% of the way to my preferred G$ SSP.

Also had GREAT first shooting cycle with my new, 2nd, Hub CAT Mob. I’m lucky that this trash MAC5K that started my mp5 journey is totally perfectly reliable with just HK extractor, spring, and full mag catch assembly.

Also, the broken in recoil rod on the MAC5K shoots noticeably softer and slower than the newer tensioned assembly on my also great ZF 5T. I think I’ll swap the AI radial break nano on the 5T for the Spooky flash hider my QD Mobster came with to see if that slows it down a bit.

And I just left the DDM4 PDW in so you could hear some 300blk subs cycling.

Anyway - ENJOY!!

CAT Mob, this time in HUB!!!

Love me some mp5’s - 2 K’s with a QD Mob and now Hub Mob. 1 full-sized mp5 with OCL Milkman.

RU3’s on both Hub suppressors.

The RU3 is a FANTASTIC tri-lug mount. The bixler-style security is the only mount I trust after coming to tri-lugs after rifle suppressors.

It’s very much worth watching the Rugged video for proper mounting - twist, tighten, pull. Avoid user error!!!

Anyway, enjoy the photos. And I REALLY hope form 1 processing speeds up for those of us waiting ever less patiently in non-Soviet states.

Can’t wait to shoot the second mob that was released just today over the weekend!

MAC5K with Mob on RU3
ZF-5T with QD Mob
ZF-5 with Milkman on RU3

90 degree locking pieces in all
ARC Fire 45/90’s in all

2 ASD mp5k lowers
1 Polymer Pew mp5 metal lower

You won’t believe how awesome they’re gonna look when they go live!!!

It’s a simple piece of printed polymer that slides on over the upper portion of your hammer.

I specifically use the Geissele mp5 hammer unjammer I bought from StrangeWatersPrints.

Flawless, and no buffer tube needed. Which makes this thing run buttery silky smooth.

I paid a company to round 2 hammers, waited 2 weeks for the hammers to return, only to find out that over $500 worth of Geissele fcg’s had been ruined by excess material removal.

I hope they make things right by me - we shall see.

Anyway, this $25 piece of plastic makes the gun run buttery smooth as no buffer short stroking is required.

90 degree locking piece is even better than the 100 while still retaining full reliability. Blazer suppressor 147 until HUSH 147 decreases price (yeah right).

Anyway, don’t be like me and pay someone to ruin your Geissele control groups. Just get the hammer unjammer and enjoy cyclic mp5 bliss!!

Was just perusing the Gram looking for any cyclic firing news or mp5 pics when the algorithm showed me the latest ARHK update.

Looks like they are now hoping for August.

They are very transparent in wanting the launch to go as well as possible.

I honestly may actually buy one just to see if it lowers fire rate compared to my AR lowers for one of my K’s.

Anyway, that’s the latest.

https://www.instagram.com/p/DZo3QmfjrSh/?igsh=dWFpaWZkYWM4ZWts

Major things I learned today are that an 80 lp is too low for my full-sized with Milkman and soft 147; and the RCM-e bolt just won’t work completely reliably for me.

I also learned my ZF5T mp5k needs the 90 lp to be fully reliable with Mob and soft Blazer suppressor 147. A JP 85 was almost there, but the 90 is completely there.

And this cool rifleconfigurator.com overlay is accurate with my mp5, and fairly accurate with long bursts on the K.

And this just co tinies to reaffirm my love of shooting this platform!

My newest mp5’s - a full-sized ZF-5 and happy accident ZF-5T K-variant.

Zenith USA quality is legit, as are the respective cans on their hosts. Milkman seems tailor-made for the 8.9” mp5, while the Mobster is glorious on any home.

Anxiously awaiting form 1’s that’ll hopefully come in August, unless things slow down further. And also waiting on an lgs call for a second Hub Mob for my trash MAC5K that started my mp5 love in the first place!

Enjoy

Here’s a great shoot from a few days back. ZF 5 full-sized with Milkman using the RU3 and ZF 5T suppressed by the Mob QD. Blazer Suppressor 147 - much better than the Phantom Defense rounds I’d been choking through previously.

As many here have said through the years, I prefer shooting the full size over my 2 K’s. I never thought I’d say that, but it’s really true. There’s just no recoil, it’s smooth as butter; it just points and shoots perfectly.

And somehow the Milkman is just the perfect combination of size, weight, sound suppression, and gas mitigation on the full mp5 with a perfect thumping tone. I don’t like the Milkman on my other K, but it seems just right on this full-size.

I do still love my K’s, especially this threaded barrel no-tri lug ZF5T with Mobster. But it is more fun to shoot the full ZF5.

I’m running an RCM 90 in the mp5 with Milkman, and it’s softer and smoother than a 100. Zero malfunctions through over 500 rounds in this configuration. Testing will continue!

I’ve got an 80 Rcm in the ZF5T which is too low for this 131 power factor 147 grain ammo and CAT Mob. The system had 2 failure to feeds out of 200 rounds. I ordered a JP 85 to see if that’s a sweet spot, otherwise I’ll use a 90.

The Mobster seems to work best with a 90 on all but the absolute hottest 147’s.

If you’ve made it this far into the read, I’d love anyone and everyone to post their Sub 9 videos. I’ve got a trash MAC5K that brought me in to my love of the mp5 platform that needs a new suppressor. I’m thinking very strongly of the Rugged Sub 9, but just want to hear and see more of it!

Thanks, and enjoy!

Wish it was full send Saturday, but instead it’s just some pictures while I day dream about the next range session.

Have at’em, boys!!!

First let me start that today was a PHENOMENAL range day. Glorious function out of my ARC Fire ZF 5 full-size and MAC5K, well, k-sized 🤷🏼‍♂️. V2 45/90’s in both.

I shot today to test the newly arrived Geissele mp5 hammer unjammer. It’s just a piece of printed PA-12CF that slides over the G$ hammer.

As you know, AR hammers in full-sized mp5’s require rounding or the use of the short-stroke recoil rod buffer tube/sleeve. It’s not hard to round a mil spec AR trigger using jig and dremel, but the G$ hammer profile is VERY hard to diy round properly. The rear of the G$ hammer will still bind the bolt to the rear of the gun even if the hammer front matches the jig.

I have one G$ SSP I borked by taking off too much material on the hammer. That busted fcg no longer has reliable semi function.

This hammer unjammer just slides over the G$ and provides the same rear profile as a rounded mil spec AR hammer. I was super skeptical that this bit of printed CF would work; but for cheap I figured I’d give it a try.

Holy smokes - it’s flawless!!! And you really want to run the full-size without a buffer. You keep the soft smooth recoil of the full mp5 and have perfectly consistent cyclic firing while not short-stroking the action. And cyclic fire with the buffer tube/sleeve is stuttery on top of being more violent.

I also want to shout out PolymerPew again. This is his metal AR full-sized mp5 lower and it’s been fantastic and flawless for me. Cheaper than the alternatives and shipped SAME DAY AS ORDER!!!

And also, I’ve just been loving the Milkman. Especially for the full size gun. I prefer my CAT Mob on my other mp5k to the Milkman on this K; but absolutely love the Milk on the full.

I’m considering a dedicated can for this tri-lug MAC5k. I’m thinking about the RICO 309, Sub 9, or a HUB CAT Mob if they are ever produced again.

Anyway, hope you enjoy!

Maybe you get tired of seeing me shoot these guns, but I just love my mp5’s! And maybe you can take a few nuggets of learning from me.

Today I shot the full-sized with the 90 degree lp and no buffer sleeve/tube on a Geissele hammer not quite sufficiently rounded. This worked great. But sadly my K also needed the 90 and right now I only have 1!!!

The full-size would not run the 100 LP without the buffer sleeve. And interestingly, the sleeve that came with my metal PolyPew lower worked great. The extra sleeve I bought from L2 prints was a millimeter or 2 shorter and would not prevent bolt behind hammer.

The 90 and no sleeve on the full size ran smoother than the 100 with buffer sleeve. The cyclic firing felt buttery smooth and consistent without the sleeve. With the 100 and sleeve there was barely noticeable but still distinct stuttering at the end of a cyclic string.

After this session I purchased a new G$ SSP and will be sending it to MidTier Defense for ARC cutting and hammer rounding.

The Geissele hammers seem to have an extremely small window between not rounded enough and destruction of perfect semi function from too much material removal. So I’ll pay to have this one done.

Lastly, while I’ve had good luck with Phantom Defense 300 blackout subs, these recent 147’s have just let me down time and again. Gassy, sparky, ammo related feeding/extracting trouble; and today I had a blown/shattered primer.

I’ll finish off the last of 2,000 rounds I bought when they last put them out in March and then I’ll be back to Suppressor 147’s.

Here are my new Zenith’s - ZF 5T and ZF 5.

The CAT Mob took 17 days to clear the Form 4 at start of 2025, the Milkman took 4 days 2 weeks ago.

The nfa sub shows Form 1’s taking just over 2 months right now - the humanity!!!

These SBT5 braces will just have to get me through until then.

And for anyone thinking of a current new clone, these Zenith’s have been literally flawless straight out of the box. And fit and finishing top notch!

Enjoy!

In heavily wooded exurbia, my neighbors are beset by a gorgeous great spotted woodpecker. He sounds not unlike this Milkman Full-sized ZF5 I've had the pleasure of breaking in!

My MAC5K introduced me to this platform, and I've utterly fallen in love with MP5's - especially when paired with cyclic firing and AR triggers, grips, and safeties!!

But through somewhat random gun acquisition, I now also own a ZF-5T and this ZF-5.

Zenith quality blows the doors off the MAC. I've had to do nothing to either the ZF 5T or the ZF 5 and they've been flawless through nearly a thousand rounds each; blasting away with armp5 lowers and subsonic suppressed cyclic firing schedules.

For literally 150 bucks more, the Zenith is a monumental upgrade over the MAC model.

Also, this polypew lower is really something else. I HIGHLY recommend his metal lower. Amazing quality, fit and finish, the price is right, and best of all - he ships what you order the day you order it!!!

The biggest trouble is that now all I can think of is shooting this ZF5 and the 5T; I am consumed!!!

In 2026, my break-in is:

1. Clean gun

2. Add suppressor

3. Toss OEM lower

4. Add AR controls with FRT

5. Break in very quickly!!

I’ve now added a Zenith mp5k and mp5 in the past 10 days. Ran them hard in their first outings. About 250 124 NATO via the FRT, then subs also FRT’ed.

Fantastic experiences!

I took a chance with the new mp5 on a smaller vendor who had actual metal lower stocks to ship - polypew is the REAL DEAL!

Extremely quality lower and he mailed this lower to me the day I bought it - SO WEIRD!!! And it’s as high quality as any other lower I’ve waited 3+ months for…

And oh yes, I figured I’d leave in the other fellows shooting unsuppressed to show how quiet the Mob and subs are!

The mp5 was a dream to shoot, and the Milkman seems tailor made for the full-sized gun.

All in all a great day!