Quoted:


I like the distinct difference between looking at the AAC mount as an engineer vs a single sampler.

That is, you CAN NOT look at the AAC 51T as an engineer or machinist and make the claim it's going to lock up tight every time. You just CAN NOT. It's got an obvious tolerance stacking issue that is going to mean that no matter how perfect one sample MAY lock up - there are going to be units where tolerances dictate that the can just falls just ever so short of hitting it's next tooth, so it has just shy of 7 degrees but more likely a free 5.25 degrees to rotate (7degrees between teeth, 3.5 to bottom to top, 1/2 of the next tooth that won't be held with any (sheer) tension, 3.5 + 1/2(3.5), equals 5.25). ....  I don't know what the real world average degrees tolerance comes out to, it's something less than 7 but enough to clearly feel if you rotate the can, so if I were to guess, I'd say 2º on average. That's not a GREAT DESIGN.  

It means that some cans will lock up at .0001º after the tooth which is awesome and tight! And it means other cans will lock up with enough to feel wobble. Which is bullshit. This is how the 51T MODIFICATION works... You take off material to allow it to rotate further to the lock just up on the next tooth. But this average means that some people will righteously got to war defending the AAC system as perfect - other people will pretend it doesn't matter their can wobbles - and realists who didn't get the luck of the draw will just modify their mounts to fit better to their can.... No matter what though, with excellent options like the Specwar, Saker, Surefire, there is just no reason to gimp yourself by initially buying in to this design NOW. In 2007/2008 when it came out, yea, it was the best available, now it is not.

AAC's 90T system improves this free rotation maximum by taking 1/2 the play, adding a taper for friction and to perfectly center the can every time (something else the 51T doesn't do well), and I wonder if the latch has been redesigned to further reduce any play, my guess is it has. The issue with the 90T system is there are fine external teeth which can get gunked up or damaged. My guess is the reason Surefire removed their fine external teeth was the same.

http://s9.postimg.org/ywy8r8anj/aac_degrees.png

So.... YES, some AAC 51T cans lock up awesome and that's great. Very quiet cans but have significant blowback/increased cyclic rate. Some AAC 51T cans wobble to the point accuracy is clearly effected. Why anyone would recommend a can with a known design flaw is fucking beyond me. The Specwar locks up tight but I haven't looked to see how it works exactly. The saker and surefire both pull backwards on their mounts making any rotational play nearly impossible, these are far better systems and imo a generation ahead of even the AAC 90T.

AAC makes an great product, but bullshit that the 51T mount is still a good design you should buy start buying into at this point in time.

Quoted:
I would avoid QD cans for precision shooting anyway. I have 1 thread on can for .308/300 WM and 1 QD for SBRs/ARs (300BLK and 5.56).
Works pretty well.

Quoted:

Explain why.

Quoted:
I would avoid QD cans for precision shooting anyway. I have 1 thread on can for .308/300 WM and 1 QD for SBRs/ARs (300BLK and 5.56).
Works pretty well.

Quoted:


I like the distinct difference between looking at the AAC mount as an engineer vs a single sampler.

That is, you CAN NOT look at the AAC 51T as an engineer or machinist and make the claim it's going to lock up tight every time. You just CAN NOT. It's got an obvious tolerance stacking issue that is going to mean that no matter how perfect one sample MAY lock up - there are going to be units where tolerances dictate that the can just falls just ever so short of hitting it's next tooth, so it has just shy of 7 degrees but more likely a free 5.25 degrees to rotate (7degrees between teeth, 3.5 to bottom to top, 1/2 of the next tooth that won't be held with any (sheer) tension, 3.5 + 1/2(3.5), equals 5.25). ....  I don't know what the real world average degrees tolerance comes out to, it's something less than 7 but enough to clearly feel if you rotate the can, so if I were to guess, I'd say 2º on average. That's not a GREAT DESIGN.  

It means that some cans will lock up at .0001º after the tooth which is awesome and tight! And it means other cans will lock up with enough to feel wobble. Which is bullshit. This is how the 51T MODIFICATION works... You take off material to allow it to rotate further to the lock just up on the next tooth. But this average means that some people will righteously got to war defending the AAC system as perfect - other people will pretend it doesn't matter their can wobbles - and realists who didn't get the luck of the draw will just modify their mounts to fit better to their can.... No matter what though, with excellent options like the Specwar, Saker, Surefire, there is just no reason to gimp yourself by initially buying in to this design NOW. In 2007/2008 when it came out, yea, it was the best available, now it is not.

AAC's 90T system improves this free rotation maximum by taking 1/2 the play, adding a taper for friction and to perfectly center the can every time (something else the 51T doesn't do well), and I wonder if the latch has been redesigned to further reduce any play, my guess is it has. The issue with the 90T system is there are fine external teeth which can get gunked up or damaged. My guess is the reason Surefire removed their fine external teeth was the same.

http://s9.postimg.org/ywy8r8anj/aac_degrees.png

So.... YES, some AAC 51T cans lock up awesome and that's great. Very quiet cans but have significant blowback/increased cyclic rate. Some AAC 51T cans wobble to the point accuracy is clearly effected. Why anyone would recommend a can with a known design flaw is fucking beyond me. The Specwar locks up tight but I haven't looked to see how it works exactly. The saker and surefire both pull backwards on their mounts making any rotational play nearly impossible, these are far better systems and imo a generation ahead of even the AAC 90T.

AAC makes an great product, but bullshit that the 51T mount is still a good design you should buy start buying into at this point in time.