Suppressors AAC 7.62 SDN-6 wiggleage?

Re: AAC 7.62 SDN-6 wiggleage?

Got mine this past Monday, locked up tight to my DPMS REPR. Ran a few rounds of subsonics into the wood pile, ran a handful of rounds through it - FGMM, NATO mil spec rounds - that can is locked up TIGHT and freaking quiet. I'd say it compares well to my Cyclone and Shadow cans but then again my ears ring a LOT but bystanders were impressed.

I like it. Got to try it on my LR308 carbine soon.
 
Re: AAC 7.62 SDN-6 wiggleage?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: normbal</div><div class="ubbcode-body">Got mine this past Monday, locked up tight to my DPMS REPR. Ran a few rounds of subsonics into the wood pile, ran a handful of rounds through it - FGMM, NATO mil spec rounds - that can is locked up TIGHT and freaking quiet. I'd say it compares well to my Cyclone and Shadow cans but then again my ears ring a LOT but bystanders were impressed.

I like it. Got to try it on my LR308 carbine soon. </div></div>


The Army rated the M110 SASS as a system that requires ear protection for those within 1M of the gun. That includes the shooter of course. The shooter's right ear noise on a M4 carbine is ~143DB with most suppressors- the AR10's may be a little louder even.

The bullet flight noise of .308 is ~151DB, but only sounds more like 143DB because it is a very short sound (in that the bullet [noise source] it is moving 2600FPS and only there for a very brief moment in time).

The human ear hears very short sounds as having ~1/2 the noise intensity, or as being 10DB lower in SPL.
 
Re: AAC 7.62 SDN-6 wiggleage?

I have a couple 51T mounts both in 762 and 556 and I have some that lock up tight and others that simply are not functional. I do notice accuracy and POI issues when the mounts are not locking up tight. I may try and lap a couple and take pics and video to document the process and some before and after shots.
 
Re: AAC 7.62 SDN-6 wiggleage?

I just did this to two of my mounts. The can locks up great now and there is zero wobble. It was also very easy with the Dremel, I didn't even take the mount off the rifle and lightly (very lightly) went over the edge. More time was spent turning the rifle than actually grinding.

anglebn.jpg


donem.jpg
 
Re: AAC 7.62 SDN-6 wiggleage?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Griffin Armament</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: normbal</div><div class="ubbcode-body">Got mine this past Monday, locked up tight to my DPMS REPR. Ran a few rounds of subsonics into the wood pile, ran a handful of rounds through it - FGMM, NATO mil spec rounds - that can is locked up TIGHT and freaking quiet. I'd say it compares well to my Cyclone and Shadow cans but then again my ears ring a LOT but bystanders were impressed.

I like it. Got to try it on my LR308 carbine soon. </div></div>


The Army rated the M110 SASS as a system that requires ear protection for those within 1M of the gun. That includes the shooter of course. The shooter's right ear noise on a M4 carbine is ~143DB with most suppressors- the AR10's may be a little louder even.

The bullet flight noise of .308 is ~151DB, but only sounds more like 143DB because it is a very short sound (in that the bullet [noise source] it is moving 2600FPS and only there for a very brief moment in time).

The human ear hears very short sounds as having ~1/2 the noise intensity, or as being 10DB lower in SPL. </div></div>

Thanks for that. I should have said, my ears ring a lot from prior service high intensity noise exposure as a flight surgeon - I spent hundreds of hours on black hawks. With helmet AND plugs I often heard crickets inside my head while flying. An audiologist told me once this was the sound of ciliated nerve cells dying in my cochlea.

I always wear ear protection when I shoot with the occasional exception of using suppressors. I didn't know the SPLs were so high even WITH the cans.

Thanks again.
 
Re: AAC 7.62 SDN-6 wiggleage?

Eurodiver,

Could you talk a little more about how to do it properly without removing the mount?

How are you keeping it even?

My mount is pretty much as close as possible to the next tooth without being able to engage, so I think that means I only need to remove the very slightest amount.

Thanks!

***I used a degreaser on the mount and internals of the SDN-6 and I was able to achieve lock on the next tooth! Holy crap is the mount tight. Truly zero wiggle at all. I'm going to guess that if I put more than minimal rounds through it the carbon will probably cause lock on the next tooth, but right not I'm very pleased.
 
Re: AAC 7.62 SDN-6 wiggleage?

Anyone who tries to correct a flawed suppressor is going to be stuck with a flawed suppressor, experienced gunsmiths notwithstanding. To pay what we pay for these suppressors and wait as long as we wait to get them, only to find they don't lock up tightly is frustrating. There is no, none, ZERO excuse for a manufacturer to send out a product in this condition, especially if installation has been done by a professional gunsmith. If the owner takes a Dremel tool and a piece of wood (how precise is that? "Jam a dowel in the...end and put the other end in a drill press...." and then clean it up with a Dremel tool? If I'm the manufacturer of a POS and don't have the ethics, morals, or ability to send out a properly functioning suppressor assembly, I'll look at this jury rigged effort at 'tampering' and use that as an excuse to void any warranty, sticking you with a POS can.

If anyone gets a Class III item that fails to function properly, mounts crooked, is loose, or causes your dog to climb into its kennel with its ears down and whimper, don't let your lust for the device override your common sense. Box it back up, suck it up, and send it back, but under no circumstances should you try this fix it yourself crap unless you are a qualified gunsmith working on your own items.

There will be, I'm sure, plenty of pushback to this opinion, and the "whine less and shoot (a defective, expensive, hard to get item) more" is sheer idiocy. The fault lies with the manufacturer, and they should be the one to fix it. And, sorry to say, if they don't care enough about their name to send out a quality product, they probably aren't going to spend a lot of time (if any) to rectify the situation.

Lastly, it truly boggle my mind, in this day of CNC production where tolerances of +/- .0001" are no big deal, how we, as consumers, get this kind of crap in the first place.

So far I've purchased 5 suppressors: an AWC Turbodyne 50 cal, a YHM Phantom with QD/Flash Hider, a SureFire FA 556SA with QD mount, a YHM Spectre thread-on, and a YHM COBRA for my .45. I threaded the barrels myself for the QD mounts - 2 firearms for the Phantom, 2 for the FA556SA, two for the Spectre, and so far, none yet for the Turbodyne. The Cobra was easy with a new threaded barrel, but I did have to recut the lug so the new barrel would lock up and go into battery - again, not a problem with the suppressor. With my equipment, the best tolerance I can get through the headstock with a spider is +/- .0005". Never a strike and everything locks up tight and straight. I've never had to adjust or adapt the suppressor itself to get anything tight. I'd urge everyone with that problem to box it back up with a polite letter, make a weekly polite phone call, and persist until it's done.

My $.02 of advice, FWIW.
 
Re: AAC 7.62 SDN-6 wiggleage?

I think AAC considers this a non issue, but they are coming out with the 90T version of their suppressors which should lock it up better. I guess it's due to all the people who complained about the can wiggling.
 
Re: AAC 7.62 SDN-6 wiggleage?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Killerwaffles</div><div class="ubbcode-body">Do you know when the 90T mount will be coming out? I just noticed my M4-2000 wiggles a bit and now its freaking me out. </div></div>

The 90t is not compatible with your M4-2000, so it's moot.
 
Re: AAC 7.62 SDN-6 wiggleage?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: cluebat</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Killerwaffles</div><div class="ubbcode-body">Do you know when the 90T mount will be coming out? I just noticed my M4-2000 wiggles a bit and now its freaking me out. </div></div>

The 90t is not compatible with your M4-2000, so it's moot. </div></div>

But it is compatible with the SDN-6, correct?
 
Re: AAC 7.62 SDN-6 wiggleage?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: jaydoc1</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: cluebat</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Killerwaffles</div><div class="ubbcode-body">Do you know when the 90T mount will be coming out? I just noticed my M4-2000 wiggles a bit and now its freaking me out. </div></div>

The 90t is not compatible with your M4-2000, so it's moot. </div></div>

But it is compatible with the SDN-6, correct?</div></div>
From what I gather it is only compatible with the new/unreleased SR5 and SR7 suppressors.
 
Re: AAC 7.62 SDN-6 wiggleage?

The 90 tooth mounts are not compatible with 51 tooth latches, from what I have heard. The increased angle of the mating cone is not going to work, either.
 
Re: AAC 7.62 SDN-6 wiggleage?

Oh yea i guess thats true. Do you think AAC might swap out the ratchet lever on my M4-2000 for one thats compatible for the 90T if i tell them i have wobble with the 51T? That should be the only thing that isnt compatible assuming the outer diameter of the ratchet mount is the same.
 
Re: AAC 7.62 SDN-6 wiggleage?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Killerwaffles</div><div class="ubbcode-body">Oh yea i guess thats true. Do you think AAC might swap out the ratchet lever on my M4-2000 for one thats compatible for the 90T if i tell them i have wobble with the 51T? That should be the only thing that isnt compatible assuming the outer diameter of the ratchet mount is the same. </div></div>

I would say no. That would be a lot of machine work to your tube.
 
Re: AAC 7.62 SDN-6 wiggleage?

No. They wouldn't do it for the 18T so they probably won't do it for the 51T. Plus the structure of the 90T is different so it's unlikely it can be done, at least not cost effectively.
 
Re: AAC 7.62 SDN-6 wiggleage?

The angle of the mating surface is different. It would be much easier to tune a mount or select a mount that mates with your ratchet-to-mating-surface relationship better. Then you're off and running with a tight fit.
 
Re: AAC 7.62 SDN-6 wiggleage?

I agree completely that the consumer shouldn't have to perform machining operations on high dollar gear sold and designed to work together and even made in the same shop. I've said good about AAC in the past, in particular about how well the Blackout flash hider and that bastard Brakeout work. But this mount fiasco won't easily be forgotten and I'll want to see the stuff work beforehand.

But it is what it is. My LMT M4 locks up with very little play, not enough worth it to go to the next teeth. It is just a 1-1.5MOA rifle anyway.

My Blackout is bit looser and may get lapped.

My FAL is very loose, almost worth sending that one back but I could fix it much faster myself. It is ALMOST there! If I were to shoot it as is though, I could almost guarantee a baffle or endcap strike. The play is obvious and it well enough for that to occur. The dia. of the muzzle is only big enough for the neck of 7.62 brass to just fit inside of it. No room for play with .30 cal projectiles for sure.

The 6.5G had to have a good deal removed and is now fixed. It locks up so damn tight I have to gently push the ratchet back in as they are that close. But it does not move, and that was critical for this tack driver.

Now say what you like, but that movement and play WILL cause the groups to open up, and BIG.

So what I'm gonna say next I'll get hammered for, but I used a whetstone while slowly turning the whole rifle by hand. It took 1.5 hours to do the one, but it turned out very well. I just used what I had to work with.

No lathe and no press, and the dremel would be a bad idea unless you are just a dremel artist. Too hard to control. But the whetstone did a fantastic job and was easy to control, keep square and didn't remove too much material. FWIW, the gritty coarse stone worked the best.

So there's yet another way of doing it, the absolute cheapest poor man's way I guess.

Other than this one thing, I love all the rest. Not like, love. It is a really nice can and really nice mounts with a shitty interface. Once you unfuck their interface issue, you have a damn nice setup.
 
Re: AAC 7.62 SDN-6 wiggleage?

It is specific to your mount(s)/suppressor combo. You are fitting them to mate tightly together.

I don't know how folks get away with wobbly suppressor accuracy???

Last weekend I was shooting IPSC plates at 800 with a nicely/tightly fitted M4-2000 6.8. Hit six in a row, and then this sudden POI shift....2 feet right and 1 foot high. Grabbed my suppressor and had a quarter notch wiggle....What the Hell??

Cleaned the Blackout and suppressor for about 15 mins until all was bright and shiny, applied some of that "controversial" Frog Lube, applied about 10 pounds of torque, and....click! Locked-up tight as before.

My accuracy is an order of magnitude better when locked-up tight. Plus, that damn wiggling drives my OCD-self nuts.
 
Re: AAC 7.62 SDN-6 wiggleage?

It's a non issue IMHO. 360*/51 leaves you with approx 7* of rotational play at worst. The thread pitch on the mount acme threads isn't steep enough for that 7* to make a difference. I'm guessing those that complain about the AAC "wobble" have never laid their hands on a Fisher/SEI suppressor or KAC QDSS/NT4 can. You want to start talking about wobble?

FWIW...I use my SDN6 on an 11.5" SBR in 5.56 with a Noveske barrel, a SR-25 EMC, and a Sako TRG-22. Two are Brakes and one is a Blackout flash hider. One just barely locks up over the next tooth for a movement free lock-up. The other two are 1/2 tooth short and have a slight amount of rotational "play". All three are sub-MOA rifles consistently.

If you're having large POI shifts when mounting the can as instructed by AAC (thread on...release latch...attempt to thread off until it locks in the first valley of the teeth) then you more than likely have a shit thread job on your barrel. Is the AAC 51T mount ideal? Maybe...maybe not. I've had nary an issue since getting mine.
 
Re: AAC 7.62 SDN-6 wiggleage?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: BayouRobert</div><div class="ubbcode-body">It is specific to your mount(s)/suppressor combo. You are fitting them to mate tightly together.

I don't know how folks get away with wobbly suppressor accuracy???

Last weekend I was shooting IPSC plates at 800 with a nicely/tightly fitted M4-2000 6.8. Hit six in a row, and then this sudden POI shift....2 feet right and 1 foot high. <span style="color: #FF0000">Grabbed my suppressor and had a quarter notch wiggle....What the Hell??</span>
Cleaned the Blackout and suppressor for about 15 mins until all was bright and shiny, applied some of that "controversial" Frog Lube, applied about 10 pounds of torque, and....click! Locked-up tight as before.

My accuracy is an order of magnitude better when locked-up tight. Plus, that damn wiggling drives my OCD-self nuts. </div></div>

I bet that if you zeroed your rifle with the can on...allowing the can to lock into the first "valley" of the teeth...it would be just as consistent with that "1/4 notch wiggle". Not trying to argue, but try it. You're not going to have a baffle strike from less than 1 tooth worth of play, and I'll bet your group size will remain about the same.
 
Re: AAC 7.62 SDN-6 wiggleage?

You are the man!



<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Eurodriver</div><div class="ubbcode-body">I just did this to two of my mounts. The can locks up great now and there is zero wobble. It was also very easy with the Dremel, I didn't even take the mount off the rifle and lightly (very lightly) went over the edge. More time was spent turning the rifle than actually grinding.

anglebn.jpg


donem.jpg
</div></div>
 
Re: AAC 7.62 SDN-6 wiggleage?

Mr CMS, I'll NEVER hit that IPSC plate at 800 with a loose M42000.

I made 12 of 15 CHEST hits @ 800 with a 10.5" 6.8 with it fitted-up tight, and...

my poi shits are so small now that I can remove the suppressor and continue to bang that plate (or be so close that I can see dirt fly and make a half or full moa adjust.)

The thing was USELESS to me before "fitted".

YOUR mileage may vary, and you are blessed if...
A) that wiggle doesn't drive you nuts, and
B) your rifle is a laser with it wiggling!
 
Re: AAC 7.62 SDN-6 wiggleage?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: BayouRobert</div><div class="ubbcode-body">Mr CMS, I'll NEVER hit that IPSC plate at 800 with a loose M42000.

I made 12 of 15 CHEST hits @ 800 with a 10.5" 6.8 with it fitted-up tight, and...

my poi shits are so small now that I can remove the suppressor and continue to bang that plate (or be so close that I can see dirt fly and make a half or full moa adjust.)

The thing was USELESS to me before "fitted".

YOUR mileage may vary, and you are blessed if...
A) that wiggle doesn't drive you nuts, and
B) your rifle is a laser with it wiggling!


































</div></div>

Sorry to hear. Have you tried contacting Mers at AAC? Had the threads checked for concentricity? The Surefire and AAC cans I've seen give wild grouping were both due to poor factory thread jobs. No issues after a cut/crown/and thread properly.
 
Re: AAC 7.62 SDN-6 wiggleage?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: cms81586</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: BayouRobert</div><div class="ubbcode-body">Mr CMS, I'll NEVER hit that IPSC plate at 800 with a loose M42000.

I made 12 of 15 CHEST hits @ 800 with a 10.5" 6.8 with it fitted-up tight, and...

my poi shits are so small now that I can remove the suppressor and continue to bang that plate (or be so close that I can see dirt fly and make a half or full moa adjust.)

The thing was USELESS to me before "fitted".

YOUR mileage may vary, and you are blessed if...
A) that wiggle doesn't drive you nuts, and
B) your rifle is a laser with it wiggling!</div></div>

Sorry to hear. Have you tried contacting Mers at AAC? Had the threads checked for concentricity? The Surefire and AAC cans I've seen give wild grouping were both due to poor factory thread jobs. No issues after a cut/crown/and thread properly. </div></div>

I think he already solved his issues.. in fact I think he's the one that recommended the mod..
grin.gif
 
Re: AAC 7.62 SDN-6 wiggleage?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: MadKap</div><div class="ubbcode-body">I'm really curious if AAC will go with a mount agonistic suppressor (ala saker) in the future. </div></div>

I doubt it. They have no QC over other MFG's muzzle devices and I doubt they'd go with anything other than a full welded tube and core. It will be interested to see what they do with the mounts. The redesign seems to be a product of customers not being happy with any movement their cans may have (although I think the actual percentage is pretty small).
 
Re: AAC 7.62 SDN-6 wiggleage?

I really need to do more testing with my sdn-6 too see if it really affects accuracy at all.

I can get minor wiggleage on my can, but I'm still shooting around .6moa on a remmy 700aac which seems decent to me.
 
Re: AAC 7.62 SDN-6 wiggleage?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: TexasGunTrustLawer</div><div class="ubbcode-body">And the 90 th mounts haven't shipped yet.</div></div>

As far as I know, 762-SDN6's won't work on a 91 tooth mount.
 
Re: AAC 7.62 SDN-6 wiggleage?

Considering it has been dead for four months, I'd say no.

Great way to pad up your posts so you can sell your shit faster I guess. Better hurry before the rush is over.

Wow, this is the second one I've seen just today! 30 posts in a little over one day.
 
Re: AAC 7.62 SDN-6 wiggleage?

Hey Stryker I appreciate your input. I have no intentions on padding to sell. I just don't have much other input to give as I'm pretty new to this whole game. I revived both threads as opposed to starting a new one because many people are told to use the search bar. I used to search bar. Found two threads on a topic I was concerned about and brought them back to the front for input. Not against forum rules in the slightest. I am aware of the 15 post limit for those under 100 and have stayed several posts below for fear of being banned. *edit 18 over the last two days, just double checked*

If I want to sell my shit I will do so in the same manner I have done for the last year, which isn't on here. As for you, if you want to give new members shit I suggest you find a different venue.
 
Re: AAC 7.62 SDN-6 wiggleage?

Well, I have an update......
My fitted suppressors have all gradually loosened to a quarter or a third-of-a-notch wiggle.
I think it's just inherent to the design.....bones and other things generally deform or fail in tension before compression.
Recoil forces on a relatively heavy screw-on device pull it forward, like a scope sliding forward on a 475 Linebaugh, and that damn wiggle returns.
???Suppressor should just screw-on and a collar should screw forward to meet it, keeping it in ever-adjustable compression......maybe someday we'll have a replacement mount that does that (or similar).
I kinda give-up, for now.
 
Solution for AAC 7.62 SDN-6 wiggleage

Well, I have an update......
My fitted suppressors have all gradually loosened to a quarter or a third-of-a-notch wiggle.
I think it's just inherent to the design.....bones and other things generally deform or fail in tension before compression.
Recoil forces on a relatively heavy screw-on device pull it forward, like a scope sliding forward on a 475 Linebaugh, and that damn wiggle returns.
???Suppressor should just screw-on and a collar should screw forward to meet it, keeping it in ever-adjustable compression......maybe someday we'll have a replacement mount that does that (or similar).
I kinda give-up, for now.

Well, this may sound crazy, but I think I have stumbled on a VERY simple solution to the frustrating “aac suppressor wiggleage” issue. Based on the theory behind BayouRobert’s remedy, I decided to try putting a 7/8” or 13/16”ID O-ring on my AAC blackout flash hider to take up the ‘in-between teeth’ play. When I screwed it on, the O-ring compressed, the suppressor teeth ratcheted right up and NO MORE wiggleage!
Observations after several hundreds of rounds:
-The thinner the OD on the O-ring, the better. You need to be able to compress enough so that the suppressor teeth are mating on the middle of the flash hider engagement surface, not just the front of the teeth.
-Viton O-rings work fine (temperature range) for plinking on the range and hunting. (+400 degrees)
-Silicon O-rings work well for going through several mags, tactical shooting, etc. (+450-500 degrees)
-If you are going to do a lot of mag dumping, you will have to use Kalrez O-rings (+600 degrees), but they are quite expensive…seriously. If you go “hot” for a bit, you can tighten it up a few more teeth (with a gloved hand, of course.)

I hope this info helps and is useful – have fun with it!
 
I just wanted to update this thread.

Many had privately and publicly chastised me, or at the very least expressed concern over my method shown above for tightening the suppressors to the mounts (on Arfcom and M4C). I guess it was too crude for some and others thought it would cause the suppressor to mount at an angle.

That's just not the case. As seen in this video at the 2:02 mark, AAC 51T cans have the bearing surface elsewhere on the FH. The area being grinded off is irrelavent (within reason) to concentricity.
SHOT Show 2012 - New from Advanced Armament - YouTube

At the time, I did not own a drill press, but that would be obviously be the ideal method. I was a frustrated consumer who knew that the value of his SS barrel and 53gr Superperformance ammo (at pre Sandy Hook prices, but still) were being wasted by a loose suppressor. I gambled, and I won. It has now been almost 2 years and I have several thousand rounds through two AAC suppressors using this method with no baffle strikes and a quantitative increase in accuracy (The results of my tests are outside the scope of this discussion, but I saw a consistent and measurable decrease in group size at 300 yards as well as repeatability when re-mounting the suppressor on my Rem700). Both suppressors mount solid as a rock and have done so for years. There have been no issues with the cans sticking to the flash hiders or loosening up. I own 3 AAC suppressors and without a doubt the 51T AAC M4-2000 will work if you're wanting to suppress a fighting carbine, but I will not be buying anymore. They're good cans at a great price, but despite the reassurances of rsilvers and others on the internet, I don't want a loose suppressor even if it is "acceptable".

IMG_20140103_102906_828_zpsd3c1e0d3.jpg
 
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There are a lot of nay-sayers out there Euro. I can tell you that I am having this issue again on my new .223 WHen it locks solid its solid but then all of the sudden I find myself dialing another .5 mil up or down @ 600 and its not reliable. With match grade ammo none the less. Sure enough the can came loose. Wasted a good $30 of 75 HPBT Superperformance to find that out. Going to have one of my friends who is more mechanically inclined work on the mount and report back. Paging you [MENTION=31553]matt2143[/MENTION]
 
Mr Gargoyle,
I will revisit the o-ring trick. Tried it once with an o-ring that was probably too thick/large in cross-section.
Looked and felt great/solid in lockup, but when I looked through the barrel and suppressor bores I was
horrified to find them far from concentric. It seems my too thick o-ring buckled and canted my m4-2000.
Thankfully, I looked before I shot.
Will try again with a thin silicone o-ring.
Thanks.