The Firing Line Forums

Go Back   The Firing Line Forums > The Hide > The Art of the Rifle: Semi-automatics

Reply
 
Thread Tools
Old September 14, 2012, 04:04 PM   #1
gizmo688
Senior Member
 
Join Date: May 31, 2011
Posts: 113
First Trip with New AR. Having feeding issues

I've got a 22" varmint built up that I took out for the first time today. I was shooting an assortment of 55g FMJ (100 rounds total). It shoots on target, but tends to function more as a bolt action. It seems to be short stroking, as it ejects the spent brass, but does not load another round OR lock back when firing the last shot. I also noticed via manual manipulation that there are times where the bolt just rides over the top of the round in the magazine without feeding it into the barrel.

First question: A guy at the range told me my rifle (specifically the bolt) was under-lubed. Is this a primary cause of a failure to cycle?

Second question: What is up with the bolt just riding over the rounds in the mag? I tried with multiple brand new PMags.

Specs:
Palmetto upper & Lower
22" .223 WOA varmint barrel
Rock River 2 stage trigger
BCM bolt carrier group
Vltor Emod A5 buffer/stock Kit

Edit: I forgot people like pictures...

Last edited by Brian Pfleuger; September 14, 2012 at 04:40 PM.
gizmo688 is offline  
Old September 14, 2012, 04:25 PM   #2
TheSILENTtype
Senior Member
 
Join Date: September 11, 2012
Posts: 139
this is a gun, best run WET WET.

Not shotgun wet, or a little wet..but wet wet. Lube that puppy good.

Have you done any 'spring work' with this?
__________________
THE SILENT TYPE
TheSILENTtype is offline  
Old September 14, 2012, 04:32 PM   #3
Father Time
Senior Member
 
Join Date: November 21, 2007
Posts: 632
Quote:
seems to be short stroking, as it ejects the spent brass, but does not load another round OR lock back when firing the last shot
Not a mag issue. It sounds like it is undergassed.
Father Time is offline  
Old September 14, 2012, 04:37 PM   #4
gizmo688
Senior Member
 
Join Date: May 31, 2011
Posts: 113
I just finished lubing the heck out of it with high temp bearing grease. Not sure what you mean by "spring work". I haven't messed with any factory springs, and I have spent a little time working in the charging handle/buffer, but not alot.
gizmo688 is offline  
Old September 14, 2012, 04:40 PM   #5
TheSILENTtype
Senior Member
 
Join Date: September 11, 2012
Posts: 139
ok. people messing with springs or messing them up when stripping / customizing usually results in a similar type of problem. so thats one issue narrowed down. how far are the casings ejecting?
__________________
THE SILENT TYPE
TheSILENTtype is offline  
Old September 14, 2012, 04:44 PM   #6
gizmo688
Senior Member
 
Join Date: May 31, 2011
Posts: 113
~8 ft from 3 o'clock to 5 o'clock. All the brass looks good. No extractor tearing.
gizmo688 is offline  
Old September 14, 2012, 04:46 PM   #7
TheSILENTtype
Senior Member
 
Join Date: September 11, 2012
Posts: 139
There is always the slight chance your sight tower (gas block) is off center a bit from the barrel and not letting enough gas through to operate the gas system. Aside from shooting a new rifle and not cleaning the cosmoline off it - this is the next most common cause in a new rifle.

My guess - you have fired off several full magazine as fast as possible and then left one of these cheapo rounds in the chamber unfired a little long. Some ammo has a varnish on the outside to prevent it from rusting......... when you accidentally leave an unfired round in a hot chamber it melts the varnish off the round and deposits it on the inside of the chamber. It makes your chamber sticky - and - slows down the ejection cycle process. Normal cleaning with oil does not remove the varnish - you need to clean the chamber will a steel chamber brush and mineral spirits or paint thinner.

What are you shooting out've it?
__________________
THE SILENT TYPE
TheSILENTtype is offline  
Old September 14, 2012, 04:47 PM   #8
TheSILENTtype
Senior Member
 
Join Date: September 11, 2012
Posts: 139
Edit : saw above for ammo.

Fact is your rifle has a 1:9 twist barrel and a recoil spring that is optiomized for the SS109 62gr tip ammo. That is a fact. The other fact - you are shooting 55gr old style 5.56mm ammo that was designed for a lighter spring and 1:12 twist barrel. This can be a problem for some new rifles.

2 -

' what is up with skipping over '

it will eject the spent shell but the bolt doesn't travel far back enough to pick up the next round and load it = SSing. As you suggested.

3 -

should have said this first, but in a forum surrounded by pros i kind of skipped it. however it still needs a break-in period before it will feed reliably. Break in periods vary, but I'd say about 500 rounds should suffice. After that, your gun should fire even the garbage. Until then, however, just keep it clean and well lubed.
__________________
THE SILENT TYPE
TheSILENTtype is offline  
Old September 14, 2012, 04:51 PM   #9
Powderman
Senior Member
 
Join Date: September 7, 2001
Location: Washington State
Posts: 2,160
Sir, looking at the picture you provided, I might have the solution.

someone has mated a carbine buffer and tube with a rifle top end.

The result is the dreaded "carfle"--a combination rifle and carbine that doesn't do either job well.

To isolate the problem, switch out your buffer, tube and stock with a normal sized stock meant for the full sized rifle. I'm willing to bet that your problem will resolve itself.

Then--if this does work for you--if you want the best stock for your rifle as it is configured, I recommend the Magpul PRS stock.

So...let us know how it works out for you.
__________________
Hiding in plain sight...
Powderman is offline  
Old September 14, 2012, 04:53 PM   #10
gizmo688
Senior Member
 
Join Date: May 31, 2011
Posts: 113
I'm hesitant to believe that the gas block isnt aligned correctly, but then again I'm new to this. The barrel had an indent for the gas block screw to fit into. It seemed pretty much right on.

Ammo - Remington 55g MC and American Eagle 55g FMJ. Both performed equally. These 100 rounds were the first ever shot out of the rifle, and I was doing 100yd target shooting after sighting it in. They were all slow methodical shots.
gizmo688 is offline  
Old September 14, 2012, 04:56 PM   #11
gizmo688
Senior Member
 
Join Date: May 31, 2011
Posts: 113
Barrel is 1:7

From what I'm reading, I just need to lube better and shoot heavier loads?
gizmo688 is offline  
Old September 14, 2012, 04:57 PM   #12
TheSILENTtype
Senior Member
 
Join Date: September 11, 2012
Posts: 139
honestly bro, i am combing research and opinions of a pal in the next window.

i personally would opt to focus on opinions by the guys more farmiliar with this firearm. my responses were courtesy of research from GlacierWolf, who builds these as match guns.
__________________
THE SILENT TYPE
TheSILENTtype is offline  
Old September 14, 2012, 05:03 PM   #13
gizmo688
Senior Member
 
Join Date: May 31, 2011
Posts: 113
Quote:
someone has mated a carbine buffer and tube with a rifle top end.

The result is the dreaded "carfle"--a combination rifle and carbine that doesn't do either job well.
Brownells site: "By using a longer receiver extension, A2 action spring, and heavier buffer, the A5 system is ideally suited for rifle length and mid-length gas systems"

Well someone is mistaken. Just not sure who it is lol
gizmo688 is offline  
Old September 14, 2012, 10:04 PM   #14
impalacustom
Senior Member
 
Join Date: January 26, 2009
Posts: 469
Powderman is dead on. That buffer is too heavy for whatever gas system that WOA is using. Put an H2 buffer in and you probably won't have any more problems. The reason they put a heavier buffer in the A5 extension is because they are using a rifle length spring and there is less tension at rest in the longer extension than there is with a carbine length spring in the carbine extension.

Other possibilities are bad gas rings, loose gas key, or partially blocked port. Being the carrier is a BCM, I'd highly doubt the key isn't done right or the gas rings are bad being new.

You don't have to have an AR sloppy wet to have one run good, that is complete crap.

Last edited by impalacustom; September 14, 2012 at 10:13 PM.
impalacustom is offline  
Old September 15, 2012, 07:24 AM   #15
Sport45
Senior Member
 
Join Date: May 25, 1999
Location: Too close to Houston
Posts: 4,069
Quote:
Originally Posted by gizmo688
it ejects the spent brass, but does not load another round OR lock back when firing the last shot. I also noticed via manual manipulation that there are times where the bolt just rides over the top of the round in the magazine without feeding it into the barrel.
Is the magazine seated fully?
__________________
Proud member of the NRA and Texas State Rifle Association. Registered and active voter.
Sport45 is offline  
Old September 15, 2012, 08:44 AM   #16
moxie
Senior Member
 
Join Date: October 17, 2006
Location: TX
Posts: 513
And, any AR should run 55gr. Might not be the most accurate in a given gun, but it should run 100%.
__________________
If you want to shoot...shoot...don't talk! Tuco

USAF Munitions 1969-1992
RVN 1972-1973
moxie is offline  
Old September 15, 2012, 09:28 AM   #17
ky hunter
Senior Member
 
Join Date: February 12, 2010
Posts: 124
Nice looking rifle how do you like that trigger I bet it shoots good. I bet if you change buffer spring to H 2 use white lithium spray grease on the bolt & Carrier + slide rails on upper it will shoot anything you put in the mag.
Have fun be safe and keep us posted.
ky hunter is offline  
Old September 15, 2012, 11:37 AM   #18
DPris
Senior Member
 
Join Date: August 19, 2004
Posts: 4,677
And I would not lube an AR with GREASE.
Use a standard OIL lube.
Denis
DPris is offline  
Old September 15, 2012, 12:04 PM   #19
gizmo688
Senior Member
 
Join Date: May 31, 2011
Posts: 113
impalacustom - I've going to put a few rounds through sloppy wet. If it still fails, I'll try an h2. Thanks.

Sport45 - yes. The mag release is in the intended slot on the magazine.

Ky hunter - I'm hoping the trigger needs some breaking in. It feels a little rough at the point of firing. My only other rifles are a heavily used Marlin 60 and a Garand (obviously also heavily used), so I'm used to a well worn trigger system.

DPris - why's that? I feel like grease sticks to the components better than oil. I use it in my 1911(slide only) and Garand with no problems. I realize that also means carbon and grime stick better to, but I don't mind the tradeoff.

Edit: Impala - Just doing some research and my Vltor kit appears to have come with a 5.3 oz buffer. Are you saying I should try a 4.6 oz buffer?

Last edited by gizmo688; September 15, 2012 at 12:12 PM.
gizmo688 is offline  
Old September 15, 2012, 12:08 PM   #20
TheSILENTtype
Senior Member
 
Join Date: September 11, 2012
Posts: 139
it may not NEED to be run 'sloppy' wet, i agree. However, running is sloppy wet should make it MORE proactive at any rate. It should also fire covered in sand, water, sawdust or any other disgusting forms of nonsense that are not ideal... give it a shot. I don't think at this point lube alone is going to help but hey, at least you get to shoot for a while haha
__________________
THE SILENT TYPE
TheSILENTtype is offline  
Old September 15, 2012, 03:12 PM   #21
gizmo688
Senior Member
 
Join Date: May 31, 2011
Posts: 113
Looks like she only plays well when wet. Just put 30 rounds through. With the exception of the first 5, everything performed flawlessly. Heres a picture of a misfeed issue that only happened for 2 of the first 5. I'm guessing they were just a result of a newly cleaned and greased rifle.
gizmo688 is offline  
Old September 15, 2012, 05:26 PM   #22
DPris
Senior Member
 
Join Date: August 19, 2004
Posts: 4,677
The AR, unlike the Garand & others, was not intended to be used with grease.
Use oil, as I said.
Denis
DPris is offline  
Old September 15, 2012, 06:25 PM   #23
Mobuck
Senior Member
 
Join Date: February 2, 2010
Posts: 2,287
OH, PALEASE GIVE US A BREAK!
The idea that a rifle upper won't funtion correctly on a carbine lower is absolutely bogus. I can swap any of 4 different barrel lengths onto either a carbine stocked lower or an A2 stocked lower and run 55-69 grain bulleted ammo as good as any.
I will assume this is/was a newly assembled upper??? If so, it should have been dripping to begin with and sputtering and smoking with every shot.
As for lube, I use CLP on the BCG, red wheel bearing grease on the cam pin&bearing surfaces of the BCG/bolt lugs, and Remlube on the trigger/hammer pins.
Mobuck is offline  
Old September 15, 2012, 08:07 PM   #24
DPris
Senior Member
 
Join Date: August 19, 2004
Posts: 4,677
And, you ARE keeping your chamber dry, right?
Denis
DPris is offline  
Old September 15, 2012, 08:19 PM   #25
gizmo688
Senior Member
 
Join Date: May 31, 2011
Posts: 113
Quote:
And, you ARE keeping your chamber dry, right? Denis
As in, am I greasing the chamber? Heck no.
gizmo688 is offline  
Reply

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 06:11 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
This site and contents, including all posts, Copyright © 1998-2014 S.W.A.T. Magazine
Copyright Complaints: Please direct DMCA Takedown Notices to the registered agent: thefiringline.com
Contact Us
Page generated in 0.17623 seconds with 7 queries