Gunsmithing Is this possible with an AR?

raider1v1

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I was thinking about this the past week or so, and I wanted to know if it was even possible. If you have a side-charge handle installed into your bolt,like this -

2008-02-06_222818_AAGrendelBuild6.jpg


and then had some kind of piece with a latch that would hold onto the knob, would it be possible to eliminate the bolt noise when shooting subsonic rounds from the AR while suppressed or would that just tear the knob off the bolt? Im taking about some kind of arm like this

371.jpg


I know it would turn it into a single shot rifle and you would have to cycle it manually and it wouldn't be practical at all, its just an idea.
 

raider1v1

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Re: Is this possible with an AR?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: _9H</div><div class="ubbcode-body">Just run a dedicated upper for this task since AR uppers are so cheap. Have the barrel maker not drill the gas hole.

This is what the do in jolly old England.

http://www.youtube.com/watch?v=QiwCSdq6ZYY </div></div>

hmm, i was kind of hoping that i would be able to retrofit the existing rifle. So the noveske switchblock does the same thing as not drilling out the gas port by shutting it off? I watched the video and the rifle was still cycling when he shut off the port..., but theres this quote from the page

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">The Switchblock has three positions; Unsuppressed, Suppressed, and OFF. The OFF position is intended for single shot operation to reduce weapon sound signature and control spent cartridge ejection. In the OFF position, no propellant gasses travel into the gas tube effectively halting the cycle of operation at the point of firing.</div></div>
 

BigBlue&Goldie

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Re: Is this possible with an AR?

Yeah, that block in particular has 3 positions; 1)Standard operation 2) Suppressed (reduces pressure to BCG allowing rifle to run cleaner and more reliably) 3)Off, which effectively cuts off the gas flow and accoplishing what you are looking for.
 

raider1v1

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Re: Is this possible with an AR?

ah, its for .750 barrels. i would have to get mine re-profiled. i think that would be good on a "purpose" built one but it would cost too much to retrofit my existing ones.
 

fast freddy

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Re: Is this possible with an AR?

paladin machine i think makes them to order, any barrel diameter, push button on/off, or 3 position. stainless or CM. and they're cheap too. think i paid about 80.00 for the last one i got.
 

jasonZ

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Re: Is this possible with an AR?

Couldn't a guy, for all extensive purposes, just install a clamp on gas block where the gas hole doesn't line up and eliminates the gas system? I'm just thinking out loud and keeping it simple cheap.
 

Jeepocabra

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Re: Is this possible with an AR?

Pretty sure jp makes an adjustable block for the larger barrels.
 

raider1v1

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Re: Is this possible with an AR?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Jeepocabra</div><div class="ubbcode-body">Pretty sure jp makes an adjustable block for the larger barrels. </div></div>

i was thinking of the one from PRI, but same idea right? coulnt you just close it all the way off? i guess the idea of a "switched" one is that you have a repeatable setting.

http://www.midwayusa.com/product/775354/...ter-steel-matte
 

9H_Cracka

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Re: Is this possible with an AR?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Raider1v1</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Jeepocabra</div><div class="ubbcode-body">Pretty sure jp makes an adjustable block for the larger barrels. </div></div>

i was thinking of the one from PRI, but same idea right? coulnt you just close it all the way off? i guess the idea of a "switched" one is that you have a repeatable setting.

http://www.midwayusa.com/product/775354/...ter-steel-matte
</div></div>

There is a difference between adjustable and selectable. The PRI is intended to be set at a specific gas level and left alone, loc titing the adjustment, as is the JP.

OP, no those rifles in the video are not functioning on their own. There is no gas system on them. They are being manually cycled as semi-auto rifles are illegal in that country.

Here is a question - so, assume you are doing as the OP intends - that is, running subsonic loads in the AR - do those loads generate enough gas to function the rifle ANYWAY?
 

Randfal

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Re: Is this possible with an AR?

yeah, turn the gas block(if its not pinned) so the hole doesn't line up.
 

Coletta

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Re: Is this possible with an AR?

Don't know if this is of concern, but poi shift often is with suppressor talk. If the gas is no longer used for cycling the bolt, then it would essentially be more efficient, which should shift poi. Also I wonder if the subsonic round could actually become a super. If it becomes supersonic, then the bolt "clack" will be the least of the noise problems. Not a problem if you are reloading though.

I know this is probably a little off topic, but it came to mind when I read this.
 

BLANKSGUNS

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Re: Is this possible with an AR?

I shut one of my AR's up for which is my night coyote gun which I run suppressed all the time. I modified the gas existing gas block, which is easily replaceable, to shut off the gas so I don't get ejection noise and blow back. Installed a Badger Ordnance Tac Latch and she is a Left handed bolt action AR now and wouldn't change it back for nothing.
IMG_1841.jpg
 

9H_Cracka

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Re: Is this possible with an AR?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Randfal</div><div class="ubbcode-body">yeah, turn the gas block(if its not pinned) so the hole doesn't line up. </div></div>

Yes, and grossly mis-align the gas tube where it meets the carrier key inside the receiver.
 

c_bass16

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    Re: Is this possible with an AR?

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: _9H</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Randfal</div><div class="ubbcode-body">yeah, turn the gas block(if its not pinned) so the hole doesn't line up. </div></div>

    Yes, and grossly mis-align the gas tube where it meets the carrier key inside the receiver. </div></div>

    Yeah, not a good idea. You'll end up wearing out the end of the gas tube and then you'll have it leak when you need it to be a good seal.

    Also, I got a PRI adjustable gas block for my 300 SAUM and even with the screw turned all the way in...it still lets enough gas squeek by to cycle perfect. I assume that is simply due to the extra pressure of the SAUM, but it was a nice surprise.

    An adjustable might not have the seal to achieve "completely OFF". If that's what you want, you may need a selectable block that truly CLOSES the hole.
     

    mobius38

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    Re: Is this possible with an AR?

    Tag as well. I like the idea of the switch block. Have a adjustable block on my OBr and it works great!
     

    bachelorjack

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    Re: Is this possible with an AR?

    Paladin push button on off gas block. This way you can change back on the fly.

    This was from 3 years ago....338 spectre build.

    dscn2957p.jpg

    dscn2961.jpg
     

    Hink

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    Re: Is this possible with an AR?

    Just for the sake of discusson, how would the AR work if one were to remove the gas tube and rotate the gas block 90, effectively blocking the gas port?

    It would obviously be a single shot, but it would negate the issues of gas tube to gas key alignment and be reversible, but at a lower cost than the switchable gas block. Changing back to semi auto would also take longer as well. Are there any other predictable downsides to this?
     

    jasonZ

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    Re: Is this possible with an AR?

    Ok, so I may not have pointed this out, but I thought it was self evident. If a person where to simply remove the tube from the gas block, or simply purchase a cheaper gas block that could be installed out of alignment with the port on the barrel, then it would be very simple to either reinstall the gas tube or simply swap the blocks out when you wish to return to normal. I apologize for that part, as it was just common sense to me. Who would leave the gas tube in when not properly aligned anyways? Sorry for the confusion and like I said it was common sense to me.