has anyone had any issues with their cans becoming loose on the mount after a few shots? I have an m42k, and 762sdn6. can mounts on the brake just fine, but after a shot or two there is a bit of slop between the can and mount. Is this normal, and does it affect accuracy? most of my guns are precision ARs and I am concerned about the issue. Thanks

slop is not good, fit should be tight, loose is a catastrophy waiting to happen

put some grease in your elbow, crank it down good or put some dope on the threads like pipe tape or something that will hold

I wouldnt say its extrmemly loose, just has some wiggle after shooting. I read another thread in a different suppressor forum saying they had the same issue. Just wondering if I should send in the cans or if this is something I can fix on my own. thread said to screw the can all the way down, tight on the brake and then back it off a bit and it fixes the problem. Has anyone heard of this before?

I reread your post, is this a QD mount?

If it's QD then my basic crank it down advice may not apply for a fix.

I'm still of the opinion loose is bad and could change POI randomly depending on how loose because I know rotating my 9mm can even when it's tight will change the POI depending on the rotation but it's repeatable because the can is tight.

yes, one is the brakeout mount, and the other is the 51t muzzle brake

Tighten down on the mount and then attempt to unscrew the can without depressing the lever. One tooth is not going to cause you enough play to create a problem...and POI shift is a non-issue as I've mounted my SDN-6 on my Sako TRG-22 and shot out to 1100 with it more than a few times. It's more accurate (if you can believe that since the TRG is a tack driver as-is) with the can on for me.

cms81586 wrote:Tighten down on the mount and then attempt to unscrew the can without depressing the lever. One tooth is not going to cause you enough play to create a problem...and POI shift is a non-issue as I've mounted my SDN-6 on my Sako TRG-22 and shot out to 1100 with it more than a few times. It's more accurate (if you can believe that since the TRG is a tack driver as-is) with the can on for me.

I did that and it has the same effect. It's tight when I screw it down, no wiggle, and one shot makes it loose. I tried to unscrew it without depressing the latch and it's loose upon doing so. I'll look into those other threads or call AAC

So just to clarify...you tighten it down, and then attempt to unscrew the can until it backs off and locks on the first "valley" of the teeth (without depressing the latch)? If this is what you're doing then that is correct. It has a very slight amount of play but it's nothing to worry about. One tooth is approx 7* of rotational play, which results in very little latteral play at the end of the can. It's not enough to cause a baffle strike and still proves to be very accurate (for all of my hosts anyways). If you've ever messed with a KAC QDSS-NT4 or Fisher/SEI .30 cal can they all move around a little.

Tightening it down and then shooting may result in a POI shift because it's not locked in the valley of the teeth, but instead the latch is lifted but not locked on the next tooth. You want to be consistent. Tighten, attempt to unthread without depressing latch until it locks, shoot.

CMS

cms81586 wrote:Tightening it down and then shooting may result in a POI shift because it's not locked in the valley of the teeth, but instead the latch is lifted but not locked on the next tooth.

That is what I'm thinking your issue is. It's not locking in the valley of the teeth as CMS mentioned.
There is a "fix" to make it a tighter fit to make it meet the next valley which requires some sanding of the flash hider/brake. There's a thread about it, but basically you sand (symmetrically) this area until the teeth enters the next valley. Just remember to break the suppressor free every so often so it doesn't get locked tight on the brake since there's less slop.

Ryo wrote:

cms81586 wrote:Tightening it down and then shooting may result in a POI shift because it's not locked in the valley of the teeth, but instead the latch is lifted but not locked on the next tooth.

That is what I'm thinking your issue is. It's not locking in the valley of the teeth as CMS mentioned.
There is a "fix" to make it a tighter fit to make it meet the next valley which requires some sanding of the flash hider/brake. There's a thread about it, but basically you sand (symmetrically) this area until the teeth enters the next valley. Just remember to break the suppressor free every so often so it doesn't get locked tight on the brake since there's less slop.

This is exactly why I haven't done the mod. Like I said...one tooth will not create enough "slop" to have any detrimental effects on accuracy of the rifle or function of the can, and I've never locked my can on the rifle after hundreds of rounds (not to mention I don't bother taking the can off when it's still hot...it stays on the rifle until I get back from shooting and everything is all cooled down). It's just a matter of how much it bothers you. You can't feel it moving around on the muzzle while shooting...and can't even really tell it's not as tight as a thread on can would be until you hold the barrel steady and grasp the muzzle end of the suppressor.

CMS

I haven't done it to mine either but thought of trying it on one FH lying around. .

cms81586 wrote:

Ryo wrote:

cms81586 wrote:Tightening it down and then shooting may result in a POI shift because it's not locked in the valley of the teeth, but instead the latch is lifted but not locked on the next tooth.

That is what I'm thinking your issue is. It's not locking in the valley of the teeth as CMS mentioned.
There is a "fix" to make it a tighter fit to make it meet the next valley which requires some sanding of the flash hider/brake. There's a thread about it, but basically you sand (symmetrically) this area until the teeth enters the next valley. Just remember to break the suppressor free every so often so it doesn't get locked tight on the brake since there's less slop.

This is exactly why I haven't done the mod. Like I said...one tooth will not create enough "slop" to have any detrimental effects on accuracy of the rifle or function of the can, and I've never locked my can on the rifle after hundreds of rounds (not to mention I don't bother taking the can off when it's still hot...it stays on the rifle until I get back from shooting and everything is all cooled down). It's just a matter of how much it bothers you. You can't feel it moving around on the muzzle while shooting...and can't even really tell it's not as tight as a thread on can would be until you hold the barrel steady and grasp the muzzle end of the suppressor.

CMS

I am new to the SDN-6 & on the 1st outing fired 2 boxes of 6.8. When I checked the can, was surprised to see that it loosened approximately 3 teeth.

It still jumps a tooth each mag but I haven't let it go more than one mag to see if it moves further.

Thank God for leather work gloves to allow me to tighten it back. I like the can but am disappointed in the mounting solution.

I have done the mod on 2 different mounts. One is on my 10.5" AR and the other is on my 18" AR. The can is rock solid on both mounts, even after fireing. Sand or grind is not a good term for this mod. Polish is a better term. DO NOT use any kind of power tool. Use some 320 and 400 grit wet dry sand paper and a hard backing for the paper. Both of mine polished out pretty quick.

VLODPG wrote:I am new to the SDN-6 & on the 1st outing fired 2 boxes of 6.8. When I checked the can, was surprised to see that it loosened approximately 3 teeth.

It still jumps a tooth each mag but I haven't let it go more than one mag to see if it moves further.

Thank God for leather work gloves to allow me to tighten it back. I like the can but am disappointed in the mounting solution.

Are you still having issues with your can? You may need to have your latch checked.

Hey all new here to the forums. Well i just spoke with AAC the other day. And the problem that i am having is this. When i first got my SDN6 with the 51 tooth hider it locked down tighter than a drum and continued that way for about 200 rounds then all of a sudden I could not tighten past the last tooth turn the other way and it pops one tooth and wiggles. AAC said not to worry that is what it is supposed to do. And this will also increase accuracy. I read of people polishing down the problem tooth to get a tight lock-on. They also said to never clean the unit or the connector "it never has to be cleaned" any thoughts on what was told to me. Or the idea of polishing with a dermal.

Thanks
Peter

I remember talking with you. It wont necessarily increase the accuracy, it will give a different point of impact when it is tightened and the latch is up on the teeth than when the latch is resting between teeth. Sometimes people will tighten all the way down(and not back it off to the valley of the teeth) and then within a couple rounds it loosens and the point of impact shifts, and this is why.

Tackshooter21 wrote:Hey all new here to the forums. Well i just spoke with AAC the other day. And the problem that i am having is this. When i first got my SDN6 with the 51 tooth hider it locked down tighter than a drum and continued that way for about 200 rounds then all of a sudden I could not tighten past the last tooth turn the other way and it pops one tooth and wiggles. AAC said not to worry that is what it is supposed to do. And this will also increase accuracy. I read of people polishing down the problem tooth to get a tight lock-on. They also said to never clean the unit or the connector "it never has to be cleaned" any thoughts on what was told to me. Or the idea of polishing with a dermal.

Thanks
Peter

It is NOT the tooth that you polish. It is the leading edge just before the teeth that you clean up. Also, do not use a Dremel. You really don't remove any material. You just clean it up.

Some people not the OP really make a big deal about the 51t mount system. I have never had any issues with my sdn6 and I use it on multiple guns. Once you lock it up you can twist it back and forth and feel a very slight loose feel. I have a feeling if it was made to lock up super tight you might have issues with carbon when trying to remove it.

ericlw wrote:Some people not the OP really make a big deal about the 51t mount system. I have never had any issues with my sdn6 and I use it on multiple guns. Once you lock it up you can twist it back and forth and feel a very slight loose feel. I have a feeling if it was made to lock up super tight you might have issues with carbon when trying to remove it.

I wish there was a "Like" button on here...

I just got my spr/m4 and before i shoot it i have a few questions. They were supplied with a mount but I'm using one I purchased while waiting on the stamp. The designs are slightly different for the mounts. Anyways there is a good amount of slop so much that you can hear the can wiggle if you shake the gun. With the miter system making the poi adjustable should there still be this much wiggle. I don't think it would cause a strike but this is my first can so what do I know.