WTK: AAC 51T ACME thread pitch once and for all!

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1968firebirdguy
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WTK: AAC 51T ACME thread pitch once and for all!

Post by 1968firebirdguy » Wed Aug 27, 2014 11:55 pm

Hey guys, hopefully one of you can help me out.

I have searched high and low but I haven't been able to find a solid be all end all answer.

what size is the ACME thread pitch on the 51T flash hider?? is it 8 tpi , 7 tpi , 7.5tpi????

any one!! my google fu seems to be lacking at the moment :-)

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john.t.little1
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Re: WTK: AAC 51T ACME thread pitch once and for all!

Post by john.t.little1 » Thu Aug 28, 2014 6:05 am

i seem to remember bender saying its close to 9.5 if i remember correctly…
"A man is known by the silence he keeps. - Oliver Herford"
"Gunpowder, treason and plot. I see no reason why gunpowder, treason
Should ever be forgot..."

1968firebirdguy
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Re: WTK: AAC 51T ACME thread pitch once and for all!

Post by 1968firebirdguy » Sun Aug 31, 2014 9:06 pm

135 views and still no solid answer?

come on guys some one has to know for sure :-)

if I had the means of measuring the threads I would figure it out myself but I don't have the the right equipment to do it correctly.

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john.t.little1
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Re: WTK: AAC 51T ACME thread pitch once and for all!

Post by john.t.little1 » Sun Aug 31, 2014 9:30 pm

Ask this guy

sizulku wrote: Hi Gunny,

Which one is perform better, using the same spacing length or different spacing length?

I build my 556 nato can based on AAC M4-2000 above. Its 2" diameter and 10" long. Nine 60-degree cones baffle. Bore is 0.252" and all spacer is 0.5".
I shot side-by-side at the range with AAC M4-2000 and unable to tell difference the sound of this can compare to AAC M4-2000 except the size and weight. I'm not happy with this result. the good thing of this can is I don't get POI shift.

Any suggestion?

Image
Image
"A man is known by the silence he keeps. - Oliver Herford"
"Gunpowder, treason and plot. I see no reason why gunpowder, treason
Should ever be forgot..."

1968firebirdguy
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Re: WTK: AAC 51T ACME thread pitch once and for all!

Post by 1968firebirdguy » Sun Aug 31, 2014 10:06 pm

John


Thanks for the reply , I did infact try asking him and I never got a response. He said he was going to check his notes and he never got back me in the post.

I may try to find one of those little fold out thread combs in ACME and take it to the flash hider I have , I have heard many different sizes from people, I know the YHM phantom threads are 8tpi and it looks really close to the AAC so I was figuring it's gotta be close to that.

Thank you again for the help

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john.t.little1
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Re: WTK: AAC 51T ACME thread pitch once and for all!

Post by john.t.little1 » Sun Aug 31, 2014 10:33 pm

You're welcome. I do believe bender knows and I seem to remember him saying it's 9.5ish
"A man is known by the silence he keeps. - Oliver Herford"
"Gunpowder, treason and plot. I see no reason why gunpowder, treason
Should ever be forgot..."

sizulku
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Re: WTK: AAC 51T ACME thread pitch once and for all!

Post by sizulku » Wed Oct 08, 2014 3:10 pm

Hi Gents.

Sorry for delays. I use metric thread number 4 as shown on the picture below.

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this is the machine
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metric thread pitch list
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my setup
Image

making aac nut
Image

result
Image

hope this help.

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john.t.little1
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Re: WTK: AAC 51T ACME thread pitch once and for all!

Post by john.t.little1 » Wed Oct 08, 2014 7:49 pm

:shock: Not worthy… thank you Sir you have done a great service for all..
"A man is known by the silence he keeps. - Oliver Herford"
"Gunpowder, treason and plot. I see no reason why gunpowder, treason
Should ever be forgot..."

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ken226
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Re: WTK: AAC 51T ACME thread pitch once and for all!

Post by ken226 » Wed Oct 08, 2014 9:45 pm

so, a 4mm pitch makes kit 6.35 tpi. I thought 9.5 would be a little odd, most manual lathes wouldn't be able to cut a 9.5 pitch i wouldnt think. I'm sure it wouldn't be a problem for a CNC.

A 4mm pitch should be doable on most machines.
02/07 FFL-SOT

Zero99z
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Re: WTK: AAC 51T ACME thread pitch once and for all!

Post by Zero99z » Thu Jan 02, 2020 6:44 pm

Sorry to hijack the thread, but if someone has the acme thread pattern for the AAC Cyclops it would be much appreciated.

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