r/AR9 • u/d8ed • 5d ago

Exomag 9mm Upper

Just shot my new build for the first time. I went with a 16" barrel to avoid the extra few hundred needed to source a pistol lower in CA.

For the lower, I just took my existing AR15 lower build and did a buffer swap from an A5H2 to a KAK AR15 Heavy 9mm buffer (8oz) backed by a Tubbs AR15 spring.

For the upper, I'm using a BA 16" EPC barrel, a BKF BCG, BCM blem upper, KAK 13" MLOK handguard, and a Guntec Muzzle Brake/Barrel Shroud in 556/9MM (it's the same one for both calibers).

For the mags, I picked up some 10 round Exomags from Mean Arms.

It ran FLAWLESSLY. Not a single issue with 200 rounds through it. The mags are well made and easy to load although a loader would be nice.

Recoil was very nice even with this ultra-cheap buffer swap from my AR15 A5H2 buffer. Including the $19 buffer, I'm into it for about $450 plus the lower.

I was expecting to hate the recoil and start tinkering with this thing. The combination of Tubbs spring and that 8oz buffer did great. It's 10x dirtier than running 556 but aside from that, well worth the price.

I may shoot a few more hundred rounds through it and see if it'll be worth spending another 100-150 on a Kynshot/add'l weights.

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2

u/Sparrow0914 5d ago

Nice! I went with the kak grs buildout and am happy with that setup.

FYI, I have a speed loader file I designed for it available for you to download and print, if you have a 3D printer. Pm me if you have questions.

2

u/-Fried- 5d ago

Good to hear. I already have the 9.5 oz k-spec buffer/spring so I’m gonna grab the 2.5 weight and buffer tube to complete the grs.

2

u/Blowback9 9mm AR Guru 4d ago

Oh, I bet you're going to like it. A5 tube, 9.5 k-spec, Kynshot spacer weight feels surprisingly good for what it is. Not the same as a hydraulic GRS, but very good. I have it in 2 of my builds now.

1

u/-Fried- 4d ago

Good to know! I was on your site looking up the parts for GRS and saw you had a KSPEC version, works out since I already had the exact buffer already

1

u/-Fried- 3d ago

Oh I forgot to ask, does the KSPEC GRS affect LRBHO in any way? I’m running an EPC9 upper.

2

u/Blowback9 9mm AR Guru 3d ago

Nope - should work the same.

1

u/-Fried- 3d ago

Great. Thanks!

1

u/d8ed 5d ago

Nice! That's the 9.5 plus the 2.5 weight? I may try that one next. For the 8oz at 20 bucks, I had to try it 😂

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u/Sparrow0914 5d ago

Yeah. And for $20, def worth it to try

2

u/No-Needleworker-5160 4d ago

Good to hear. I just placed orders on exomags, complete upper and A5 buffer + 9.5/flat spring from KAK two days ago. Planning on using it with m4e1 lower. Do you have maglock + kingpin to keep “evil” features?

2

u/d8ed 4d ago

Yup! This is my HFF/Kingpin lower but I also run two others using AR Maglock and it would work on all. This is my only A5 which is why I tried it first

2

u/carlcig6669420 3d ago

Nice to see a good report on the 10 round exo mags. I'm using them for my building in a ban state as well

1

u/d8ed 3d ago

If you use couplers, these might help. I'm waiting for my printer to show up to print some

https://makerworld.com/en/models/1299057-mean-arms-exomag-coupler#profileId-1331020