Suppressed AR troubles.

kawasakifreak77 · June 26, 2014, 03:06 AM

Okay so I got my first can (YHM Phantom) & I freaking love it! Its primary host is my blackout bolt gun & it works fantastic.

For fathers day I got dad a few trick goodies for his AR (RRA .556 16" carbine) including the QD attachment to run my can on his gun.These days he's very concerned about losing anymore hearing, so I think he'll really enjoy it.

So I take it out to sight it in (upgraded the sights) & at first the gun ran fine but it slowly started hanging up. Everything seemed to be okay until the mag ran dry (Troy 30 rounder) the bolt locked back, I topped off the mag, inserted it & go to drop the bolt & it won't go forward. I tug on the charging handle which got it to go forward mostly but I still had to use the forward assist to get the bolt in battery. Sometimes while firing, after the initial recoil of the gun, I felt that the bolt was still traveling forward, like it was lagging behind for lack of a better term.

I figured I might try different ammo & magazines & try it without the can, also. I used 5 different types of ammo (all 55 grain stuff) the Troy mag, an old Colt 20 round stick & a new Pmag 20 rounder. All combinations of ammunition & magazines exhibited the same characteristics. Bolt hesitates to go forward after locking back on a dry mag. Looking at it, it appears as if the bolt is too far back if that makes sense.

After all that, trying it without the can, it did the same thing. By this point however I figured the gun was gummed up.

From what I understand about suppressors they make more gas go into the gun. Reading up on ARs, it seems I need a heavier buffer or stronger spring, correct?

If that is the case, will it run 100% unsuppressed also?

It has to be able to do both since my dad can only run my can with me present.

Any help in this matter is greatly appreciated. I want to share the benefits of suppressed shooting with my dad.

Theohazard · June 26, 2014, 01:45 PM

I'm not exactly sure what's happening specifically in regards to your bolt. You might be having fouling issues (you should never need to use the forward assist under normal operation). You also might be having issues with the bolt release catching on the wrong part of the bolt/BCG. But whatever the exact issue, I'd be willing to bet that the problem would be fixed by a heavier buffer.

Most ARs are slightly over-gassed already. And then when you add a silencer it gets even worse. The bolt starts unlocking before the gas pressure has dropped, and this leads to ejection and over-fouling issues. Adding a heavier bolt will slightly delay the bolt unlocking, which will lead to smother functioning and a little bit less fouling.

Also, keep in mind that shooting suppressed can cause lubrication issues that wouldn't ever be a problem on an un-suppressed gun. Soon after getting my can, I had my selector lever freeze up. The reason was that the extra fouling was gumming up the spring and detent. So I took them out, cleaned them off, and lubed them up with Froglube paste and I haven't had an issue since. Froglube paste works amazingly well on suppressed ARs.

What is the current buffer weight? Basically, you use the heaviest buffer that will still allow the bolt to lock back on an empty mag while shooting unsuppressed. The proper buffer weight should allow it to function well both suppressed and unsuppressed. If this rifle has a carbine-length gas system, my guess is it would run best with an H2 buffer.

kawasakifreak77 · June 26, 2014, 05:37 PM

Thanks for all the info man! I have no idea what buffer weight this thing has but I'll look into it.

Theohazard · June 26, 2014, 07:01 PM

No prob. And to find out the buffer weight, just look at the face of the buffer that contacts the BCG; it's usually stamped there. If there's nothing there, it's probably a standard-weight carbine buffer; if it says "H" then it's slightly heavier; "H2" is a little heavier than that; and so on. My guess is you have a standard-weight buffer right now, so there won't be any markings. Though you might have an "H" buffer.

Also, there might be other issues going on that a heavier buffer doesn't fix, but this is the easiest and most obvious fix. In my experience, when someone has issues with running a suppressed AR, it's almost always an issue of having a buffer that's too light.

Sharkbite · June 26, 2014, 07:16 PM

After the buffer, since this is a 556 gun you might want to try an adj gas block. Overgassed 556 guns can benifit from this

tmorone · June 26, 2014, 07:41 PM

I had a similar issue. Went to heavybuffers.com on a recommendation from someone here and it got my gun running right. Reason to go there, over say... Spikes for an H3 is that they have even heavier tungsten filled buffers. Slowed down an overgassed/suppressed gun and made it run flawlessly. Also shoots just fine without the can.

However, your best (although more expensive) fix would be an adjustable gas block. The buffer just corrects the symptom, where the block will correct the cause.

kawasakifreak77 · June 27, 2014, 10:26 PM

I see now what you're saying there.

I scaled the buffer in my dad's gun & it came in at right under 3 ounces which from what I understand makes it a carbine buffer. Is there any reason I couldn't buy an H3 & trade the weights out one at a time until the gun would run with & without a can? Seems like the most cost efficient way to do this, versus buying one buffer & hoping it works.

June 26, 2014, 03:06 AM	#1
kawasakifreak77 Senior Member Join Date: December 16, 2007 Location: St. John, Ks. Posts: 267	Suppressed AR troubles. Okay so I got my first can (YHM Phantom) & I freaking love it! Its primary host is my blackout bolt gun & it works fantastic. For fathers day I got dad a few trick goodies for his AR (RRA .556 16" carbine) including the QD attachment to run my can on his gun.These days he's very concerned about losing anymore hearing, so I think he'll really enjoy it. So I take it out to sight it in (upgraded the sights) & at first the gun ran fine but it slowly started hanging up. Everything seemed to be okay until the mag ran dry (Troy 30 rounder) the bolt locked back, I topped off the mag, inserted it & go to drop the bolt & it won't go forward. I tug on the charging handle which got it to go forward mostly but I still had to use the forward assist to get the bolt in battery. Sometimes while firing, after the initial recoil of the gun, I felt that the bolt was still traveling forward, like it was lagging behind for lack of a better term. I figured I might try different ammo & magazines & try it without the can, also. I used 5 different types of ammo (all 55 grain stuff) the Troy mag, an old Colt 20 round stick & a new Pmag 20 rounder. All combinations of ammunition & magazines exhibited the same characteristics. Bolt hesitates to go forward after locking back on a dry mag. Looking at it, it appears as if the bolt is too far back if that makes sense. After all that, trying it without the can, it did the same thing. By this point however I figured the gun was gummed up. From what I understand about suppressors they make more gas go into the gun. Reading up on ARs, it seems I need a heavier buffer or stronger spring, correct? If that is the case, will it run 100% unsuppressed also? It has to be able to do both since my dad can only run my can with me present. Any help in this matter is greatly appreciated. I want to share the benefits of suppressed shooting with my dad. __________________ Looking for oddball ammo. Tracers, AP, whatcha got?

June 26, 2014, 01:45 PM	#2
Theohazard Senior Member Join Date: April 19, 2012 Location: Western PA Posts: 3,829	I'm not exactly sure what's happening specifically in regards to your bolt. You might be having fouling issues (you should never need to use the forward assist under normal operation). You also might be having issues with the bolt release catching on the wrong part of the bolt/BCG. But whatever the exact issue, I'd be willing to bet that the problem would be fixed by a heavier buffer. Most ARs are slightly over-gassed already. And then when you add a silencer it gets even worse. The bolt starts unlocking before the gas pressure has dropped, and this leads to ejection and over-fouling issues. Adding a heavier bolt will slightly delay the bolt unlocking, which will lead to smother functioning and a little bit less fouling. Also, keep in mind that shooting suppressed can cause lubrication issues that wouldn't ever be a problem on an un-suppressed gun. Soon after getting my can, I had my selector lever freeze up. The reason was that the extra fouling was gumming up the spring and detent. So I took them out, cleaned them off, and lubed them up with Froglube paste and I haven't had an issue since. Froglube paste works amazingly well on suppressed ARs. What is the current buffer weight? Basically, you use the heaviest buffer that will still allow the bolt to lock back on an empty mag while shooting unsuppressed. The proper buffer weight should allow it to function well both suppressed and unsuppressed. If this rifle has a carbine-length gas system, my guess is it would run best with an H2 buffer. __________________ 0331: "Accuracy by volume."

June 26, 2014, 05:37 PM	#3
kawasakifreak77 Senior Member Join Date: December 16, 2007 Location: St. John, Ks. Posts: 267	Thanks for all the info man! I have no idea what buffer weight this thing has but I'll look into it. __________________ Looking for oddball ammo. Tracers, AP, whatcha got?

June 26, 2014, 07:01 PM	#4
Theohazard Senior Member Join Date: April 19, 2012 Location: Western PA Posts: 3,829	No prob. And to find out the buffer weight, just look at the face of the buffer that contacts the BCG; it's usually stamped there. If there's nothing there, it's probably a standard-weight carbine buffer; if it says "H" then it's slightly heavier; "H2" is a little heavier than that; and so on. My guess is you have a standard-weight buffer right now, so there won't be any markings. Though you might have an "H" buffer. Also, there might be other issues going on that a heavier buffer doesn't fix, but this is the easiest and most obvious fix. In my experience, when someone has issues with running a suppressed AR, it's almost always an issue of having a buffer that's too light. __________________ 0331: "Accuracy by volume."

June 27, 2014, 10:26 PM	#7
kawasakifreak77 Senior Member Join Date: December 16, 2007 Location: St. John, Ks. Posts: 267	I see now what you're saying there. I scaled the buffer in my dad's gun & it came in at right under 3 ounces which from what I understand makes it a carbine buffer. Is there any reason I couldn't buy an H3 & trade the weights out one at a time until the gun would run with & without a can? Seems like the most cost efficient way to do this, versus buying one buffer & hoping it works. __________________ Looking for oddball ammo. Tracers, AP, whatcha got?

June 26, 2014, 07:16 PM	#5
Sharkbite Senior Member Join Date: November 4, 2013 Location: Western slope of Colorado Posts: 3,679	After the buffer, since this is a 556 gun you might want to try an adj gas block. Overgassed 556 guns can benifit from this

June 26, 2014, 07:41 PM	#6
tmorone Senior Member Join Date: October 22, 2010 Posts: 221	I had a similar issue. Went to heavybuffers.com on a recommendation from someone here and it got my gun running right. Reason to go there, over say... Spikes for an H3 is that they have even heavier tungsten filled buffers. Slowed down an overgassed/suppressed gun and made it run flawlessly. Also shoots just fine without the can. However, your best (although more expensive) fix would be an adjustable gas block. The buffer just corrects the symptom, where the block will correct the cause.