Feeding problems with .223 but not with 5.56 why?

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[ARCHIVED THREAD] - Feeding problems with .223 but not with 5.56 why?

Posted: 7/29/2012 9:27:37 AM EDT

I have a pistol that is soon to been an SBR (assuming i get approved) that shoots 5.56 just fine but as soon as I put .223 in it will not fully eject the spent case and try to feed another round. Is this because of my barrel being so short that I doesn't have enought back pressure and if so what do I need to do to fix that. It will be suppressed one day if that makes any difference on the answer. This is my first AR-15 so I was a little heartbroken when this problem happened I thought I had done something wrong.

Posted: 7/29/2012 9:49:42 AM EDT

[#1]

.223 is underpowered vs. 5.56. Sounds like it's short stroking. You can try changing out your buffer to a lighter one, or possibly try a weaker buffer spring. But when you go surpressed, you'll probably have to change it back to the configuration it's in now.

Posted: 7/29/2012 10:19:04 AM EDT

[#2]

Quoted:
.223 is underpowered vs. 5.56. Sounds like it's short stroking. You can try changing out your buffer to a lighter one, or possibly try a weaker buffer spring. But when you go surpressed, you'll probably have to change it back to the configuration it's in now.

I concur.

Posted: 7/29/2012 10:47:55 AM EDT

[#3]

So I am guessing with this gun there is no perfect world where I can run either or. Good to know thanks guys

Posted: 7/29/2012 11:59:15 AM EDT

[#4]

Saleendude07 have you tried taking an empty mag, inserting one round, chambering that round, firing it and see if the bolt is left held open? If not then I would try that.

If the bolt is NOT left held open then I believe it is short stroking and further troubleshooting would be necessary in order to isolate the specific problem.

A good weapon should fire anything. I don't care if it is 223, 5.56, Wolf, etc...

Posted: 7/29/2012 3:59:26 PM EDT

[#5]

Quoted:
Saleendude07 have you tried taking an empty mag, inserting one round, chambering that round, firing it and see if the bolt is left held open? If not then I would try that.

If the bolt is NOT left held open then I believe it is short stroking and further troubleshooting would be necessary in order to isolate the specific problem.

A good weapon should fire anything. I don't care if it is 223, 5.56, Wolf, etc...

I just did what you said. I tried it with both 5.56 and .223 and it locked the bolt back with both. Where do I need to go from here as far as troubleshooting? Does it have something to do with my gas system? Would I need to run an adjustable gas block on this type of set up?

Posted: 7/29/2012 4:50:11 PM EDT

[#6]

Quoted:

Quoted:
Saleendude07 have you tried taking an empty mag, inserting one round, chambering that round, firing it and see if the bolt is left held open? If not then I would try that.

If the bolt is NOT left held open then I believe it is short stroking and further troubleshooting would be necessary in order to isolate the specific problem.

A good weapon should fire anything. I don't care if it is 223, 5.56, Wolf, etc...

I just did what you said. I tried it with both 5.56 and .223 and it locked the bolt back with both. Where do I need to go from here as far as troubleshooting? Does it have something to do with my gas system? Would I need to run an adjustable gas block on this type of set up?

I'm not an expert at diagnosing, but it 'might' be over gassed and the action may need slowed down. I am NOT sure about that so hopefully more experienced troubleshooters chime in. There is a Troubleshooting forum here just for this. Some prefer to jump straight to getting a heavy buffer if I'm not mistaken and others do as you mentioned and use an adjustable gas block. The Syrac Ordnance adjustable gas block has a locking detent so the adjustment can never move