After serving its time of approx 150 day NFA jail stint, my M4SD-L came home this past Friday.  I had stopped by my LGS after a vet visit and to my surprise, I was welcomed by a “hey, your Tax Stamp arrived yesterday” (I missed the email).  

I had mounted it to my 11.5”SBR after its first arrival to the shop and “cleared” their back room a few times, but it wasn’t till I got it home and mounted it to a loaded weapon where I realized the improved balance given the lighter weight at the muzzle; from a guy who does long hikes with a rifle, I was suddenly overcome with a sense of joy.  
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M4SD-L
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30SD-K (w/ a DIY Cerakote FDE paint job)
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AAC Omni 5.56 (owned since 2003)
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Background.   I got into NFA around 2003 with my first Form 1 SBR and the AAC Omni pictured above.  I had expanded my collection of SBRs over the years, but my modest collection of suppressors remained limited to three cans from the early 2000’s (AAC Omni 556, AAC Aviator 22LR, and AAC Evo-9) until the panic of the current POTUS and Covid brought me to purchase the Griffin Armament 30SD-K as a compliment to my Sig 716i.  

The 30SK-K has been a solid performer and my my go-to, hiking/woods on both 11.5” and 14.5” SBR’s until fellow ARFCOM buddy AmishBill pointed me towards the newly introduced M4SD-L.  

As with the Omni, I’ve always preferred a can that can lock up on an A2 flash hider (works on issued US Amy issued M4A1’s) and the GateLoc was an instant hit.

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The M4SD-L is riding along with me on an overnight, out of state trip, but standby all, as I’m headed to the range this afternoon noon when back home.   More to follow.

As the person behind both your first and most recent can, I'm always happy to help a friend spend their money.

I saw a video from 11b trying out their new can. An iphone a few feet away from the ejection port doesn't capture the sound differences well - but if you listen, you can tell the muzzle blast is (mostly) replaced by the sonic crack. I can imagine the real life improvement.

The only closing comment I can offer - You Bastage, getting yours before I get mine.

The AAC Omni is wild, never seen one of those before.



As far as I'm concerned, that applies to both of you. My wait hasn't even started because I've been torn between this and another M4SD-K, but I think this just sold me on the L.

Range trip review.  Yep, I love this can.
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I’ve got video, but had my phone too close to the rifle; I don’t think it would do it justice to post, even if I knew how to do.  Regardless, it suppresses very well.  

I started with a three round group un-suppressed to confirm zero, then another three rounds suppressed to ascertain zero shift.  I tossed my Peltors after that.  Hearing safe and then some.  Again, I’m just a hard user of things, and am not set up for, nor can I relate further with any scientific terms related towards tone, blast, concussion, noise/decibel, etc.

When shooting my 30SD-K on my 5.56 rifles with the GateLoc to the right side, I get no horizontal shift in zero, only a nice 1-2” drop below zero depending on the ammo/bullet weight.

I started with the GateLoc on the M4SD-L on the right side, getting a horizontal string, then switched it to the left resulting in a tight group.

My best results at grouping/zeroing came from my initial 20 rds of unknown brand 62 gr green tip, then I was chasing the target center after using Winchester white box M193 / 55 gr while shooting at dusk, and through ground vegetation.   I was running out of time, and too lazy to turn the truck around to headlight the target.

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I’ve been a victim of a very gassy can with the ancient AAC Omni forever.  M4SD-L gas is very negligible, barely noticeable with the EcoFlow baffles. I intentionally used a standard CH and was pleasantly surprised yet again.  I'll use a PRI Gasbuster next trip, but doesn’t seem like it’ll be needed with this can.

It's nice to be in the 21st century can wise, thanks Griffin.

Mine’s still in jail. How’s yours compare in signature reduction and blowback vs your 30SD-k? Since that’s one I’ve had for a while. I’m very much looking forward to this one.

Mine is setting in a box 20 feet from me. Once its pristine newness is properly documented, I have a 14.5 M4 clone-ish to try it on. I can't wait!

Any updates to this? Looking to get one myself, real world experiences are appreciated since there isn’t a ton of info out on these yet.