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Super-short .300 BLK cans and setup?

This topic can be found at:
https://sigforum.com/eve/forums/a/tpc/f/380105858/m/3280066474

September 17, 2020, 02:29 PM
Rob Decker
Super-short .300 BLK cans and setup?
So...I think I may be diving headfirst down the .300 BLK rabbithole.

The idea of a very compact package with near-AK ballistics appeals to me...I think a 9" MCX in .300 is in my near future. I don't think I'd go the Rattler route...I've played with one but I don't like what that short a barrel does to velocity, especially with subsonic.

In that application (supersonic ammo) the suppressor is more to keep me from feeling like my head has been hammered flat if I fire the thing without ears. I'd want one as short as possible. So far the shortest I've found is the SilencerCo Omega 9K, which clocks in at 4.7" and is rated (loudly at 138 db) for supersonic .300 BLK. That gives me plenty of ballistic power in a suppressed platform that's still clocking in at shorter than my issued M4.

Are there any shorter/fatter options out there that I'm missing? The arbitrary line I drew for myself was 5.5" so it's shorter than the carbine.

And going into ammo...what are some solid defensive options in supersonic? I've been googling but given the .300 traffic on here I can't imagine I'm the first person on the board to dive down that rabbithole.

This message has been edited. Last edited by: Rob Decker,


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Death smiles at us all. Be sure you smile back.
September 17, 2020, 02:38 PM
sigfreund
After a bit of research I settled on the Hornady 110 grain V-MAX 300 BLK load as something with decent energy and would probably always expand well from a short barrel.




6.4/93.6

“Wise men talk because they have something to say; fools, because they have to say something.”
— Plato
September 17, 2020, 03:26 PM
mew
I like the expansion of the new 190 sub-x from Hornady, the gel test video looks great.
https://www.hornady.com/ammuni...gr-sub-x-subsonic#!/


"All that is necessary for the triumph of evil is for good men to do nothing"
Edmund Burke
September 17, 2020, 03:31 PM
esdunbar
My home defense gun is a Sig Rattler. I have an Omega 300 hanging off the end. I went shorter barrel and longer suppressor so I could tame the blast of supers. My defense round of choice is the Barnes Vortx 110 gr.
September 17, 2020, 05:42 PM
mew
yeah I have a 300 Omega on mine too, only have SB 200gr subs for now due to the shortage but I would say on my 8.5" they are hearing safe for sure quiet, seems like a .22LR sound wise. 5.56 with the same supressor is tolerable on my 11.5" but not safe. Will get some 110 Hornady when they come back.


"All that is necessary for the triumph of evil is for good men to do nothing"
Edmund Burke
September 17, 2020, 05:59 PM
creslin
I assume you mean MCX - not the MPX.
I have both of these (9mm MPX and .300blk MCX) - with an Omega9k on each one.
I've only run subsonic rounds through the MCX and it works like a champ.





This is where my signature goes.
September 17, 2020, 10:48 PM
fritz
quote:
Originally posted by Rob Decker:
Are there any shorter/fatter options out there that I'm missing? The arbitrary line I drew for myself was 5.5" so it's shorter than the carbine.

Cans tend to max out in diameter of around 1.5". Larger diameter cans may interfere with sights on certain firearms. Understand that a really short can won't be quiet.

The Omega 9K doesn't have all that much noise reduction. I've shot one briefly, ran the numbers comparisons, and have one in jail. It will be used with a Wilson AR9G and a Glock 17, primarily with 147 grain subsonic ammo.

The Omega 300 mentioned above is a true rifle can, and thus will easily handle 300 blk supersonic. Noise suppression is good. It is 7.1" long.

I have a Surefire SOCOM mini for my AR15s in 223 and 300 blk. It's a quality can with good noise suppression, and it handles 308 Win. It is 6.4" long.

I have shot my 300blk into soft dirt and sand, but not ballistic gel. Subsonic ammo IMO:
- I was not impressed with the accuracy of any subsonic ammo I shot. Didn't matter what brand or type of bullet. For defensive distances under 25 yards, the poor accuracy may not matter to some.
- Most heavy 308 bullets don't expand or fragment at subsonic speeds. Some of those I pulled from dirt looked they they could be reloaded. Hornady's 190 SubX bullets at least expanded at the front end of the bullet, however the rear of the bullet looked unchanged.

Supersonic 300blk ammo IMO:
- FMJ bullets of 125-150 grains don't seem to fragment or expand. Pulled from dirt, most looked good enough to reload.
- SMK 125 bullets were the most accurate of anything I tested. The HP nose expanded a bit in dirt, but not into a true mushroom shape.
- Hornady 110 VMax loads expanded the most for me. It tends to be an accurate load for many barrels.
- 125 SST loads expanded almost as much as 110 Vmax, but penetrated dirt a little further. The 125 SST bullet tended to remain more intact, as the jacket sometimes separated with the 110 Vmax. This was an accurate bullet in my barrel, but the factory loads popped primers, which jammed the AR.
- 110 and 120 Vortx loads were accurate for me. The front end of the bullets expanded fairly well, with the rear half remaining intact. They penetrated dirt pretty far.
Bottom line -- I think the ammo industry is still working on the perfect defensive bullet for 300blk, both supersonic and subsonic.
September 17, 2020, 11:59 PM
Chowser
I’m running a Sandman-K on a 6” barrel setup. Does fine with Hornady 110 and 190 ammo.



Not minority enough!
September 19, 2020, 07:37 AM
sigarmsp226
quote:
Originally posted by mew:
I like the expansion of the new 190 sub-x from Hornady, the gel test video looks great.
https://www.hornady.com/ammuni...gr-sub-x-subsonic#!/


Mew - Thanks for posting this info about this round...Decided real quick that with this loaded round going for over $2.00 a round I would just buy the projectile and load some myself....That idea went South real quick as there is not a box of these pills to be found anywhere for sale for loading...Guess this is one I missed the boat on and will have to wait until next year to load and try....

Thanks again for posting...Guess I have been living under a rock for a while to have missed the release of this bullet and round...Mark
September 19, 2020, 04:28 PM
mdblanton
I’ve got the Rugged Razor 7.62 on a .300 Blackout pistol. It’s 0.9” longer than your desired setup but does deliver around 130 dB for .300 Blackout (per their data). However, they also have the modular Micro30 at 5” in the shortest configuration: Rugged Micro30. Might be worth a look.

Michael
December 24, 2020, 12:20 PM
Rob Decker
Thanks all for the input. Current shenanigans have continued and delayed my acquisitions process so it looks as if this will be a 35th birthday present to myself...


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Death smiles at us all. Be sure you smile back.
September 20, 2021, 12:50 PM
Rob Decker
Reviving the necro-thread!




SIG LVAW Clone Sheet

So apparently I wasn't the only one to have this idea...SIG sold a number of this build to SOCOM on the Gen I MCX platform called the Low Visibility Assault Weapon (LVAW). It uses a 6.75" barrel in .300 BLK, so stubby, but not as stubby as the 5.5 inch Rattler barrel.

I'm debating a direct clone of this setup and all the PITA that would be, or trying to come up with an LVAW MkII.


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Death smiles at us all. Be sure you smile back.
September 21, 2021, 08:39 AM
dry-fly
I think the Dead Air Wolfman in its short configuration could be a solid choice for .300 Blk. I think it’s even rated for supers.


"Attack life, it's going to kill you anyway." Steve McQueen...
September 21, 2021, 09:40 AM
KSGM
I am fixing to get a ~9" .300BLK Sig 556 put together. Not super short, but certainly short-ish. I intend to use a pretty long can though; direct-thread Gemtech HVT. I don't plan to shoot supers at all.
September 29, 2021, 01:02 PM
xmod
For my 300 blk rattler, I’m looking at the energetic arms vox k and a q cherry bomb muzzle break. The vox k is the shortest I have found at 4.4”, but it is a loud suppressor.
October 21, 2021, 12:40 PM
xmod
Update - I did purchase the vox k. May end up direct thread mounting. My dealer said he could taper that mount to match the tapwr on my rattler barrel. I am skeptical of direct threading because they always loosen.
October 21, 2021, 01:01 PM
KSGM
I wish I had dabbled with direct-thread sooner. I like the compactness and simplicity. I use a strap wrench, with the receiver on a reaction rod, to tighten it. I also put some thread tape on the muzzle threads. The thread tape is by no means a proven thing; I read about it in the context of preventing pistol cans from loosening, and figured it couldn't hurt. If you can have the DT mount tapered to match, that would make it that much more solid.