Suppressors AAC 762 SDN-6 on a precision bolt rifle

[The Zebra]

As of this moment, my only 30 cal can is my SDN-6. It serves mostly for use on 8" 300BLK and 11.5" 5.56 but I also wanted to be able to suppress my .308 precision rifle. After putting some range time down with and without the can attached, I have some notes to share with others in hopes that someone else has tried their N-6 on a bolt gun. I am looking for others experiences to compare my own to.

The rifle is a Rem 700 SPS Tactical chambered in 308 Win. The loads are 175 SMK over 44.7gr of Varget in Lapua brass and a CCI BR-2 primer.

Rifle has a 200 yard zero.
Unsuppressed dopes:
6.5 moa @ 400 yards
14.25 moa @ 600
19 moa @ 700

Suppressed:
8.25 moa @ 400
16 moa @ 600
21.25 moa @ 700
26.75moa @ 800

Notes: The suppressor was spot on with the unsuppressed dopes for the first ~4 rounds. After that, the POI changed dramatically. Once the can was "hot", the POI changed anywhere from 1.75-2.25 MOA. Did the can cool down between strings to give me the .75 difference? I can't say one way or the other. The change was low at 6 o'clock. I am fully aware that a QD can is not ideal for a precision rifle but I was at least hoping for a consistant POI shift. At 800 yards, a .75 MOA variable could mean the difference of 6 inches. I will continue to do more testing when I can but I am a bit disappointed to say the least. Anyone else try a SDN-6 on a precision rifle?

 

[phxfa]

Re: AAC 762 SDN-6 on a precision bolt rifle

is the suppressor locked on the QD mount solid with no 'wiggle'? My LMT didnt shoot for shit with a 762SD on it (51t) till I tuned the break so it locked up tight

 

[The Zebra]

Re: AAC 762 SDN-6 on a precision bolt rifle

The lockup on my suppressor is very tight with all 3 mounts that I use. I do not have the "wiggle" that some others with similar cans report.

 

[Icallem]

Re: AAC 762 SDN-6 on a precision bolt rifle

I'm 9 days away from being 6 months of waiting for stamp on 2 of these.
This has me worried, but I've visited with the ginsmith about working on the brake until this locks up tight.

I'll report as soon as I can. Hopefully real soon!

 

[JSTARSZ]

Re: AAC 762 SDN-6 on a precision bolt rifle

My first question: did you rezero when you put the suppressor on and what was the poi change from on to off? If so, was it a 2 MOA difference?

 

[The Zebra]

Re: AAC 762 SDN-6 on a precision bolt rifle

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Icallem</div><div class="ubbcode-body">I'm 9 days away from being 6 months of waiting for stamp on 2 of these.
This has me worried, but I've visited with the ginsmith about working on the brake until this locks up tight.

I'll report as soon as I can. Hopefully real soon!</div></div>

I wouldn't be worried. The can works as intended on my other hosts. I didn't expect it to be a "precision rifle can" so I can't say that I've been let down. At this point, my only concern with the bolt gun is the varying POI shift between a cold can and hot can. I just want the POI shift to be repeatable no matter how many rounds have been through it.

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: JSTARSZ</div><div class="ubbcode-body">My first question: did you rezero when you put the suppressor on and what was the poi change from on to off? If so, was it a 2 MOA difference? </div></div>

Attached the suppressor after gathering all of the unsuppressed dopes. I did not re-zero with the suppressor on.

 

[Dog Doc]

Re: AAC 762 SDN-6 on a precision bolt rifle

I just got my AAC SDN-6 and have used it on my Rem 700AAC. I actually get more POI shift than you.. I am seeing a 4 moa drop at the 6:00 position. I dont have access to the range you have so 300yds is max for me, but it shot very well! Most of my scopes are mil/mil now so I just dial 1 mil over and it hits dead center.

 

[JSTARSZ]

Re: AAC 762 SDN-6 on a precision bolt rifle

I don't have an AAC SDN-6 but i have other QD mounts and I pretty much gave up on ever trying to predict long shots with them. I went to a direct thread on and a Thunderbeast 30P-1 and have not looked back. My QD's stay on SBR AR's where extreme accuracy is not a huge issue. Good luck to you in your quest as it can be frustrating with the QD mounts. Some get lucky and others are just frustrated.

 

[The Zebra]

Re: AAC 762 SDN-6 on a precision bolt rifle

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: JSTARSZ</div><div class="ubbcode-body">I don't have an AAC SDN-6 but i have other QD mounts and I pretty much gave up on ever trying to predict long shots with them. I went to a direct thread on and a Thunderbeast 30P-1 and have not looked back. My QD's stay on SBR AR's where extreme accuracy is not a huge issue. Good luck to you in your quest as it can be frustrating with the QD mounts. Some get lucky and others are just frustrated. </div></div>

I don't think I'm going to let this frustrate me. I never had the expectations for this can to be my precision rifle can. I do plan to snag a 30P-1 when I can get the scratch together for it.

 

[RFtinkerer]

Re: AAC 762 SDN-6 on a precision bolt rifle

Great, I knew I made a mistake by going to the 762-SDN-6. I'm on a wait for one right now, and I actually DO expect to use this on my precision rifle. Do you all think I could just use locktite on a dedicated muzzle brake to turn the QD into a thread mount and get repeatable POI shift? Or am I stupid for even thinking that?

 

[JSTARSZ]

Re: AAC 762 SDN-6 on a precision bolt rifle

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: RFtinkerer</div><div class="ubbcode-body">Great, I knew I made a mistake by going to the 762-SDN-6. I'm on a wait for one right now, and I actually DO expect to use this on my precision rifle. Do you all think I could just use locktite on a dedicated muzzle brake to turn the QD into a thread mount and get repeatable POI shift? Or am I stupid for even thinking that?</div></div> I think before you go off the deep end you should wait until you get it and start working with it. You may get a very predictable POI shift and it will be fine.

 

[Dog Doc]

Re: AAC 762 SDN-6 on a precision bolt rifle

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: RFtinkerer</div><div class="ubbcode-body">Great, I knew I made a mistake by going to the 762-SDN-6. I'm on a wait for one right now, and I actually DO expect to use this on my precision rifle. Do you all think I could just use locktite on a dedicated muzzle brake to turn the QD into a thread mount and get repeatable POI shift? Or am I stupid for even thinking that? </div></div>
Just so you know, I am not at all disappointed in my accuracy with the sdn-6. Actually it is very accurate! Like I said earlier this is only to 300yds so far but I was more accurate suppressed than unsuppressed. Wait and see... I felt like you until I got it and couldn't be happier.

 

[KYS]

Re: AAC 762 SDN-6 on a precision bolt rifle

You need to revaluate your bolt gun load if you are getting that much deviation in your dope. My SDn6 is on my 6XC all the time and it barely had any POI change and it has tightened up my 200 yard groups which is what I zeroed at.

 

[CTown137]

Re: AAC 762 SDN-6 on a precision bolt rifle

Since you are using the can on other rifles, including AR's in 556, what type of shifts are you getting with and without the can on those. Do you get drastic shifts when it heats up on those?

 

[The Zebra]

Re: AAC 762 SDN-6 on a precision bolt rifle

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: CTown137</div><div class="ubbcode-body">Since you are using the can on other rifles, including AR's in 556, what type of shifts are you getting with and without the can on those. Do you get drastic shifts when it heats up on those?</div></div>

Both the blackout and 556 uppers have a T-1 so its pretty hard to tell if the suppressor is giving me POI changes. I haven't benched those guns either. I've only shot those offhand and at steel. I can say that the blackout easily hits 12" steel at 300 yards using supers with or without the can so if it is changing POI, its minimal.

 

[Dog Doc]

Re: AAC 762 SDN-6 on a precision bolt rifle

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: KYS338</div><div class="ubbcode-body">You need to revaluate your bolt gun load if you are getting that much deviation in your dope. My SDn6 is on my 6XC all the time and it barely had any POI change and it has tightened up my 200 yard groups which is what I zeroed at.

</div></div>

So what is an acceptable POI shift? I was under the impression that this can be a common occurrance with any supppressor.

 

[KYS]

Re: AAC 762 SDN-6 on a precision bolt rifle

POI change at 200 yards is one thing but to have that much vertical dispersion with the can on is not right. Try some factory ammo? See if there is much change.

 

[The Zebra]

Re: AAC 762 SDN-6 on a precision bolt rifle

I honestly don't think its my load but I appreciate the advice. Before I begin the load development process again, I am going to do more testing. I will be sure to report back after I get to the range tomorrow. My plan is to shoot groups with and without the can. I also plan on getting the can "up to temp" and shooting for groups again to see if that makes any difference.

 

[remau308]

Re: AAC 762 SDN-6 on a precision bolt rifle

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: JSTARSZ</div><div class="ubbcode-body">I don't have an AAC SDN-6 but i have other QD mounts and I pretty much gave up on ever trying to predict long shots with them. I went to a direct thread on and a Thunderbeast 30P-1 and have not looked back. My QD's stay on SBR AR's where extreme accuracy is not a huge issue. Good luck to you in your quest as it can be frustrating with the QD mounts. Some get lucky and others are just frustrated. </div></div>

Have you ever shot with a Surefire? Mine has absolutely no POI shift, and I use my old dope to shoot out to 500yards so far with no shift. Some QD's may have shift, but my Surefire hasn't had any so far.

 

[jrgfox]

Re: AAC 762 SDN-6 on a precision bolt rifle

I was out a Tac Pro last month with my friend who has a new 20 inch AI MK3 and we were shooting clays at 500 without the can. Then we put on his SDN-6 can mounted on a 51 tooth adaptor and without any changes in dope were still able to hit clays at 500 yards. This was my first experience with any AAC rifle cans as all of mine are surefire. I will say i was impressed with the performance of the can as well as the lack of impact shift. I don't know if this is common performance from these or if he just got lucky with his set up and the specific can that he got. I noticed you have a longer barrel with a much thiner barrel profile than my friends AI. Im not sure how much you were shooting but the extra weight on the end of a longer barrel as the barrel heats up could explain some of that shift.

 

[KYS]

Re: AAC 762 SDN-6 on a precision bolt rifle

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: armedzebra</div><div class="ubbcode-body">I honestly don't think its my load but I appreciate the advice. Before I begin the load development process again, I am going to do more testing. I will be sure to report back after I get to the range tomorrow. My plan is to shoot groups with and without the can. I also plan on getting the can "up to temp" and shooting for groups again to see if that makes any difference. </div></div>

I didn't say change your load.... I said might be worth it to try some factory ammo to get a baseline. Then, maybe go back and redo your hand loads. Just a though.

 

[jrgfox]

Re: AAC 762 SDN-6 on a precision bolt rifle

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: armedzebra</div><div class="ubbcode-body"> My plan is to shoot groups with and without the can. I also plan on getting the can "up to temp" and shooting for groups again to see if that makes any difference. </div></div>

I think that if heat is the issue, it has more to do with the barrel sagging as it heats up with the extra weight of the can on the end of it than it does with the temp. of the can.

 

[The Gump]

Re: AAC 762 SDN-6 on a precision bolt rifle

My N6 shifts POI .3 mil on both windage and elevation repeatably on my .260.

 

[Icallem]

Re: AAC 762 SDN-6 on a precision bolt rifle

Just picked up a pair of AAC-7.62 cans. The wait is over. The 50 mile trip home lasted forever, wanting to see how they would match up on the 51 tooth adapter.

1st rifle, 20 inch, with MTU size barrel, and it locked up tight. POI off very little, but 1/2-3/4 inch between the next 4 shots. As it warmed up it started stacking them on top of each other, so I had 5 30cal holes up and down. Did that twice and by then the heat had it where It was tough to tell what was going on.

Same rifle went back this morning and it did the same on the first group. 1st shoot 1/2-3/4 inch high, then next 4 in a bughole. Direction I shoot with the sun would not let me shoot more this morning, but will try more this evenging.

2nd rifle, screwed the can on and it wiggles up-down, side-side, so I didn't even shoot with it, just called the gunsmith and he is going to turn the adapter down to where the can locks on tight.

So far I'm really happy with the first one and think it best if I don't ( I know me ) even try the second one until I give it every chance to be good.

 

[cchurchi]

Re: AAC 762 SDN-6 on a precision bolt rifle

I've run a 762-SDN-6 on my GAP crusader and my testing showed it increased my group size slightly as well as blowing a large amount of carbon past the mount which then coats the front of my barrel, which is tan and has flutes, so it's hard to get clean.

I have since ordered a TBAC, and only use the SDN on my DPMS SASS and 300BLK.

 

[shibby575]

Re: AAC 762 SDN-6 on a precision bolt rifle

With mine the POI change is about .5 moa at 100 yrds. Now that being said if I don't make sure it's tight between shots the POI goes to 2+ MOA and my groups open up to about 1.5 MOA when usually it's a .5 moa rifle. I need to tune the adapter, and hopefully it fixes the problem, if not I'm gonna send it to AAC to see WTF is wrong. If not fixed it will be quite the disappointment. Now I just need to find the time to work over the FH.

 

[The Gump]

Re: AAC 762 SDN-6 on a precision bolt rifle

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: cchurchi</div><div class="ubbcode-body">I've run a 762-SDN-6 on my GAP crusader and my testing showed it increased my group size slightly as well as blowing a large amount of carbon past the mount which then coats the front of my barrel, which is tan and has flutes, so it's hard to get clean.

I have since ordered a TBAC, and only use the SDN on my DPMS SASS and 300BLK. </div></div>

Same problem with the blow by. When I get the funds I plan to order a TBAC. Maybe a .338.

 

[peaceatwar]

Re: AAC 762 SDN-6 on a precision bolt rifle

Any updates? I am weeks from getting my can and and want to know whether I should just sell it and order a different can or give it a shot. I know I will have a better chance at recuperating funds(+ tax stamp) if I sell it new vs used.

 

[RFtinkerer]

Re: AAC 762 SDN-6 on a precision bolt rifle

Don't give up the ship, IMO. I was concerned about it before I got it, as you can see earlier in the thread. Now that I have it, mind you I haven't done any REAL testing, but initial impressions are no accuracy impact and ~1 MOA shift 6:00 on my 308 bolt. It locked up tight as well on it. Now with the AR-15 it's a different story. It was loose on the mount and I noticed decreased accuracy. Not that my AR-15 was that accurate to begin with, but it did seem worse. Also more like a 2 MOA shift, again 6:00. I will tighten up the mount by shaving the Brakeout surface and see if I can get it back to normal.

 

[RonA]

Re: AAC 762 SDN-6 on a precision bolt rifle

The SDN-6 is excellent with sub-sonic .300 Blackout,good with supersonic blackout, but doesn't do as well with .308. Seems like it's better suited to the smaller capacity case.

 

[Pappasniper]

Re: AAC 762 SDN-6 on a precision bolt rifle

I run mine on a Remmy 20 inch 5R in 308. Half inch groups. Do not sell it. I have run it on two guns. One gun is a .75 MOA gun, With or without can. Its an Heavy CL FN SPR.

Its non sense. All my AAC's shoot great even when they dont lock perfect. About one inch shift. Depending on the can and gun, no more.

 

[Pappasniper]

Re: AAC 762 SDN-6 on a precision bolt rifle

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: JSTARSZ</div><div class="ubbcode-body">My first question: did you rezero when you put the suppressor on and what was the poi change from on to off? If so, was it a 2 MOA difference? </div></div>

Very good point.

 

[chainring]

Re: AAC 762 SDN-6 on a precision bolt rifle

I tuned my mounts for my N6 for rock solid lockup before ever firing it on the bolt gun. Works nicely.

 

[Cephus91]

Re: AAC 762 SDN-6 on a precision bolt rifle

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: PappaSniper</div><div class="ubbcode-body">I run mine on a Remmy 20 inch 5R in 308. Half inch groups. Do not sell it. I have run it on two guns. One gun is a .75 MOA gun, With or without can. Its an Heavy CL FN SPR.

Its non sense. All my AAC's shoot great even when they dont lock perfect. About one inch shift. Depending on the can and gun, no more. </div></div>

This is refreshing to hear. I am waiting for my stamp on my SDN-6, and plan on using it on my 20" .308 SPS Tac (and my AR). Have been anxiously reading this post.

 

[RFtinkerer]

Re: AAC 762 SDN-6 on a precision bolt rifle

No shit there. Just got mine. Locks up tight now, but I don't want it to get bad...I'm loving it. Quiet as a 22, so my neighbors don't think I'm blasting ~3000 ft lbs down range.