How can I turn an A2 FSB into an adjustable gas block?

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LavaRed
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How can I turn an A2 FSB into an adjustable gas block?

Post by LavaRed » Mon Feb 24, 2014 6:27 pm

Inquiring minds need to know.
Thanks,
LavaRed
"There are no stupid questions, only stupid people". -MAJ MALFUNCTION

JFettig
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Re: How can I turn an A2 FSB into an adjustable gas block?

Post by JFettig » Mon Feb 24, 2014 8:44 pm

Not enough meat in a standard A2 gas block but ones that do have the meat, I drill and tap 6-32 thread into the port just above the barrel, its .295" forward from the shoulder and .500" from the centerline of the barrel, install set screw.

Here are some examples to look at.
http://www.rainierarms.com/?page=shop/d ... ct_id=3183
http://media.midwayusa.com/productimage ... 775354.jpg
http://blogs.militarytimes.com/gearscou ... 00x333.jpg

This one goes in from the end
http://www.midwayusa.com/product/321768 ... teel-matte

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ChimeraPrecision
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Re: How can I turn an A2 FSB into an adjustable gas block?

Post by ChimeraPrecision » Mon Feb 24, 2014 9:24 pm

I'm going to drill and tap 2 holes 90 degrees apart.

1 to obscure the orifice, and a second hole for brass set screw to lock the orifice screw down. Just like the seekins.

Ideally the gas adjustment would be toward the muzzle so you can adjust with hand guards in place
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JohnnyO
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Re: How can I turn an A2 FSB into an adjustable gas block?

Post by JohnnyO » Tue Feb 25, 2014 12:09 am

I made this one from Ti and used SLR's adjustment system

Image
Image
Image

Historian
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Re: How can I turn an A2 FSB into an adjustable gas block?

Post by Historian » Tue Feb 25, 2014 11:44 am

JohnnyO wrote:I made this one from Ti and used SLR's adjustment system

Image
Image
Image
Excellent work!

Compliments.

Thanks for showing.

May I say that your results satisfy Chuck Berry's advice: "Johnny Be-Goode"

<< http://www.youtube.com/watch?v=AEq62iQo0eU&feature=kp >>
1956 Cadillac Sedan de Ville, windows down, music blaring, real Presidents
like Ike, Kennedy, etc.

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gunny50
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Re: How can I turn an A2 FSB into an adjustable gas block?

Post by gunny50 » Wed Feb 26, 2014 7:02 am

JohnnyO wrote:I made this one from Ti and used SLR's adjustment system
Image[/url]

Johnny, are you done with the parts that attach to this nicely machined block and adapter?

Gunny

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JohnnyO
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Re: How can I turn an A2 FSB into an adjustable gas block?

Post by JohnnyO » Wed Feb 26, 2014 9:10 am

No not yet

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LavaRed
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Re: How can I turn an A2 FSB into an adjustable gas block?

Post by LavaRed » Wed Feb 26, 2014 4:16 pm

Thanks guys! The knowledge is greatly appreciated.
"There are no stupid questions, only stupid people". -MAJ MALFUNCTION

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