Adams Arms and 300blk

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[ARCHIVED THREAD] - Adams Arms and 300blk

Posted: 1/17/2015 12:34:08 AM EDT

has anyone had success getting the Adams Arms pistol length piston kits working with 300 BLK and shorter barrels? Ideally for both sub and supersonic rounds.

Posted: 1/17/2015 5:03:49 AM EDT

[#1]

AA sells complete 300blk guuns now so i'm guessing it works just fine.

Posted: 1/17/2015 11:27:53 PM EDT

[#2]

They only go down to 12.5". I was hoping for someone who has got it working down below 10".

Posted: 1/18/2015 5:48:17 PM EDT

[#3]

Quote History

Quoted:
They only go down to 12.5". I was hoping for someone who has got it working down below 10".

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PWS, maybe? There is a reason you don't see 300 BLK piston setups with pistol length gas systems -- there just isn't enough gas/pressure/dwell to drive the system with subsonic loads at pistol length gas.

Posted: 1/18/2015 11:41:18 PM EDT

[#4]

Upcoming Sig MCX features a 9" bbl and runs 300BLK subsonic.

Posted: 1/19/2015 9:49:51 AM EDT

[#5]

Quote History

Quoted:
Upcoming Sig MCX features a 9" bbl and runs 300BLK subsonic.

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It's a "short stroke" piston system, but that's where the similarities end as far as piston systems go -- it doesn't even have a regular AR15 buffer tube, buffer, or spring assembly. Read more here: Sig MCX

Like I said, you likely won't like see any of the traditional and/or conversion piston systems being able to run subsonic 300 BLK, and that's where most people shop for piston systems, mainly because they are well known quantities that are consumer friendly when it comes to pricing.

Posted: 1/20/2015 2:42:55 PM EDT

[#6]

Quote History

Quoted:

It's a "short stroke" piston system, but that's where the similarities end as far as piston systems go -- it doesn't even have a regular AR15 buffer tube, buffer, or spring assembly. Read more here: Sig MCX

Like I said, you likely won't like see any of the traditional and/or conversion piston systems being able to run subsonic 300 BLK, and that's where most people shop for piston systems, mainly because they are well known quantities that are consumer friendly when it comes to pricing.

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Quote History

Quoted:

Quoted:
Upcoming Sig MCX features a 9" bbl and runs 300BLK subsonic.

It's a "short stroke" piston system, but that's where the similarities end as far as piston systems go -- it doesn't even have a regular AR15 buffer tube, buffer, or spring assembly. Read more here: Sig MCX

Like I said, you likely won't like see any of the traditional and/or conversion piston systems being able to run subsonic 300 BLK, and that's where most people shop for piston systems, mainly because they are well known quantities that are consumer friendly when it comes to pricing.

Thanks for link to the review on TheTruthAboutGuns; a good article and the second video is a must see. " I said the better option would be adding chrome exhaust pipes to the side of the can and maxing out the powder charge."

Posted: 1/20/2015 3:32:27 PM EDT

[#7]

I've built a 10.5" with the AA XLP using the lightened carrier and it runs like a sewing machine. Currently waiting on my tax stamp so no report about subs with a can yet, but so far I couldn't be happier.

Posted: 1/20/2015 3:41:02 PM EDT

[#8]

Quote History

Quoted:
I've built a 10.5" with the AA XLP using the lightened carrier and it runs like a sewing machine. Currently waiting on my tax stamp so no report about subs with a can yet, but so far I couldn't be happier.

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If it's cycling subs without the can, then it will with the can.

Someone needs to try an 8" barrel and report back. I bet the outcome will be different.

Posted: 1/20/2015 10:56:32 PM EDT

[#9]

Quote History

Quoted:

I've built a 10.5" with the AA XLP using the lightened carrier and it runs like a sewing machine. Currently waiting on my tax stamp so no report about subs with a can yet, but so far I couldn't be happier.

http://i1327.photobucket.com/albums/u680/jhend170/Mobile%20Uploads/20140910_223710_zpsx6ijbnb6.jpg

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What barrel did you use? Any info on port size?

Posted: 1/21/2015 1:09:57 PM EDT

[#10]

are you running the AA system full open or adjusting the gas some?
and yes, + info on gas port size please.
also interested in trying to get a 8.5" piston 300blk to run subs w/ can.
and a JP silent capture spring (if anyone has tested that combo)

Posted: 1/21/2015 1:16:00 PM EDT

[#11]

Sorry, no idea on port size.. the barrel is a 10.5" Bergara so maybe you can research or contact them?

Gas setting is in the middle of the 5 with 115gr supers and no cyclic issues. Means there's plenty more gas to be had should I need it.

As for the JP they are nice and all but I grease my spring liberally and it's essentially silent, for about $90 less.

Subs will always run better with a can than without, so shouldn't be an issue.

Posted: 2/2/2015 1:43:54 AM EDT

[#12]

AA has stated somewhere that the lightened carrier is the key to their piston design working with 300 blk in shorter barrels. They sell a 9" barreled upper/pistol so I would imagine 8.5" would work fine

Posted: 2/8/2015 11:37:58 PM EDT

[#13]

If you can answer I've got a few questions.

What barrel, recoil spring and buffer did you use?

Thanks in advance.

Posted: 2/9/2015 12:56:55 AM EDT

[#14]

Quote History

Quoted:
They only go down to 12.5". I was hoping for someone who has got it working down below 10".

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I spoke with Cody at AA and was informed the have a 9 inch upper coming. They are waiting on barrels. There was an article about the 300 line release and it list the 9 inch, so i verified that it was indeed coming.