SW99 2 Posted March 27, 2012 So I took my brand new AR out for a small test drive today. I only put 40 rounds through it. I ran into 2 problems: First problem was, I would get 2-3-4 rounds out with no issues then a round would chamber (bolt fully closed) but when I went to go pull the trigger nothing would happen. I would have to pull the charging handle to eject the unfired round in the chamber and chamber the next round, then it would be fine. This happened a few times with both mags throughout the session. Second problem, when ever I would shoot the last round in the mag the bolt would catch open as it should, but the charging handle would stay in the closed position. When you shoot the last round and the bolt catches open isn't the charging handle supposed to also be fully open? The ammo I used was 5.56mm (62) FMJ M855 Penetrator (green tips) 20 rounds of this (This box cost me $11, as i bought it last week and brought it with me today) I also used 20 rounds of something else (forgot to save the box) I do know it was 5.56 for sure not .223 as the person behind the counter asked if i could shoot 5.53 ammo and thats what she game me. It was in a brown box and cost $9. (this box i purchased today) Here are the specs on my upper: Stag-15 Model 2H Pre-Ban Caliber....5.56 Nato Chamber Upper......Forged and Mil Spec. Sights..... Flip Up Rear/Front Post Barrel.....16" Chrome Lined 1/9 Twist Break......A2 Flash Hider Anyone have any ideas as to whats going on? Is it the ammo I'm using? If so what should I be using? I know you can shoot .223 rounds in a 5.56 chamber (but not the other way around) should I be using .223 instead? Other than the above it shot great. at 23 yards out slightly 4 o'clock of center mass. Im looking to get it on a 100yrd outdoor range soon and will see how it is at at range. Thanks for all the help!! Quote Share this post Link to post Share on other sites
bbk 188 Posted March 27, 2012 First problem was, I would get 2-3-4 rounds out with no issues then a round would chamber (bolt fully closed) but when I went to go pull the trigger nothing would happen. I would have to pull the charging handle to eject the unfired round in the chamber and chamber the next round, then it would be fine. This happened a few times with both mags throughout the session. This sounds like a possible ammunition problem (bad primers), though possibly something wrong with your AR. Internally, make sure you didn't lubricate the firing pin. I'm one of those who believe that wetter the bolt, the better-- but you never want to lubricate the firing pin as that can cause a build up of gunk/carbon, which can result in your issue of FTF (failure to fire). Another possibility is just a bad firing pin, though this seems pretty rare from my experience. Second problem, when ever I would shoot the last round in the mag the bolt would catch open as it should, but the charging handle would stay in the closed position. When you shoot the last round and the bolt catches open isn't the charging handle supposed to also be fully open? No, the charging handle for ARs are non-reciprocating. In short, it means that unlike systems that have reciprocating charging handles (AKs for example), the charging handle is stationary throughout the firing process. In fact, the charging handle should be closed unless you are specifically doing something with it (similar to how, IMO, the dust cover should be closed unless you're firing). Quote Share this post Link to post Share on other sites
MarkWVU02 47 Posted March 27, 2012 Charging handle wont lock back. It stays in place. Let me think about the ammo problem and get back to you. Quote Share this post Link to post Share on other sites
Vlad G 345 Posted March 27, 2012 1) What do you men that gun wouldn't fire? Would the trigger move? Did the hammer drop inside the gun? Did the trigger reset after the previous shot? 2) Hell no, the charging handle shouldn't lock back or it would hit you in the face. The charging handle ONLY moves when you manipulate it, all the rest of the time it sits happily inside the upper receiver or all AR shooters would be missing teeth. The bolt locks back, a new magazine in inserted and the bolt release button pressed. Quote Share this post Link to post Share on other sites
bbk 188 Posted March 27, 2012 Follow up question to your first question. When you pulled the trigger, what happened? Did the trigger feel mushy or was there a definite *click*? Were there imprints of the firing pin (even if slight) on the casing of the unfired round? Quote Share this post Link to post Share on other sites
Sigman 41 Posted March 27, 2012 On the rounds that didn't fire. Are you sure the bolt was fully closed? If so, did you check for light primer strikes? Did this happen with both boxes of ammo? On the last shot, the bolt remains open, but the charging handle remains closed. Quote Share this post Link to post Share on other sites
SW99 2 Posted March 27, 2012 Thanks for the answer on the Charging handle, after thinking about it, it makes sense. lol As for the first problem. The round would chamber like i said above but when i went to pull the trigger it wouldn't do anything, no movement at all, almost like it was being blocked as if the safety was on. After pulling the chugging handle and the round in the changed ejected, it would then chamber a new round and it would work fine again for a few rounds. Hope this helps. Thanks again!! Quote Share this post Link to post Share on other sites
Vlad G 345 Posted March 27, 2012 1) make sure you left the trigger reset. The AR trigger likes to move back forward for some distance before being ready to fire. 2) if you let go FULLY of the trigger and you press it again and it does not move, the odds are one of three things have happened: a) The hammer did not engage the sear and moved forward with the bolt b) Your disconnector might be confused c) your safety is getting moved around. All of those conditions indicate a possible problem with the trigger group, have someone who knows what they are doing look at it. Quote Share this post Link to post Share on other sites
SW99 2 Posted March 27, 2012 Thanks for the help so far! I just pulled the BCG and cleaned and lubed in the recommend spots (dried and cleaned firing pin). Im going to try to go again on thursday to see if that helped and to pay closer attention to the things you mentioned Vlad. The ammo can be ruled out? Quote Share this post Link to post Share on other sites
intercooler 41 Posted March 27, 2012 Ah... First off, there are no "preban" legal uppers in nj. You are risking serious consequences by your ignorance. Get a pinned comp on that upper before you do anything. If it has a bayonet lug, you must remove it ASAP! Quote Share this post Link to post Share on other sites
lunker 274 Posted March 27, 2012 On a completely separate note... I noticed you emphasize that you have a pre-ban upper that mentions an A2 Flash Hider. I assume that this is a mistake or is kept somewhere other than New Jersey. Our fine state does not recognize the distinction between pre-ban and post-ban. Basically, if you own a pre-ban configuration and did not register it as an assault weapon back in 1990, you became a felon when NJ instituted its assault weapon law. Hell, even New York recognizes pre-ban guns as legal. we suck. 1 Quote Share this post Link to post Share on other sites
MarkWVU02 47 Posted March 27, 2012 I'd check the disconnecter and the hammer and trigger springs. My buddy had a reversed trigger spring and he'd get double taps and times when the trigger wouldn't reset. Once fixed he hadn't had a problem. It's really easy to reverse a spring or put one in where it looks fine but isn't. I would say my first inclination is that there's something wrong with the hammer and disconnecter not engaging. Let us know if you solve the problem and if you can post some picks looking down into the trigger group. Quote Share this post Link to post Share on other sites
alowerlevel 77 Posted March 27, 2012 Ah... First off, there are no "preban" legal uppers in nj. You are risking serious consequences by your ignorance. Get a pinned comp on that upper before you do anything. If it has a bayonet lug, you must remove it ASAP! On a completely separate note... I noticed you emphasize that you have a pre-ban upper that mentions an A2 Flash Hider. I assume that this is a mistake or is kept somewhere other than New Jersey. Our fine state does not recognize the distinction between pre-ban and post-ban. Basically, if you own a pre-ban configuration and did not register it as an assault weapon back in 1990, you became a felon when NJ instituted its assault weapon law. Hell, even New York recognizes pre-ban guns as legal. we suck. Guys, if you have looked at his build thread http://njgunforums.c...er-get-old-lol/ you can see that hes got a brake and the bayo lug cut off. He probably just copied the info from Stags site and forgot to add that its jersey legal. Quote Share this post Link to post Share on other sites
Vlad G 345 Posted March 27, 2012 The ammo can be ruled out? You can't really rule anything out until you figure out what is actually wrong, it just smart debugging, but that said I can't think of a situation where the ammo would be the issue. If you had severely underpowered ammo or a gas flow problem and the gun short stroked or didn't feed the next round I would consider it, but I can't think of a set of circumstances under which the gun has bolt has enough rear movement to eject the spent case a feed a new one and NOT reset the trigger. If the trigger bits don't move, the hammer doesn't all, the firing pin doesn't hit the ammo so the quality of the ammo is not even relevant. My GUESS is that there is something wrong with your trigger group or there is something else going on you haven't told us about yet. Like maybe your thumb is moving the safety around a bit? EDIT: actually I CAN think of an ammo problem, namely if you are blowing out primers and they primers have made their way into your lower. Visually inspect your trigger group and make sure there are no primers stuck in there, there shouldn't be any brass bits in there. Quote Share this post Link to post Share on other sites
SW99 2 Posted March 27, 2012 Guys, if you have looked at his build thread http://njgunforums.c...er-get-old-lol/ you can see that hes got a brake and the bayo lug cut off. He probably just copied the info from Stags site and forgot to add that its jersey legal. Thanks alowerlevel. I did copy and paste it from the site. My entire AR is NJ spec, specifically ordered it that way, stock and all so I didn't have to worry about being out of NJ spec (not that they would have shipped it to me) and pinning anything. Sorry for the confusion above. Quote Share this post Link to post Share on other sites
SW99 2 Posted March 27, 2012 I'd check the disconnecter and the hammer and trigger springs. My buddy had a reversed trigger spring and he'd get double taps and times when the trigger wouldn't reset. Once fixed he hadn't had a problem. It's really easy to reverse a spring or put one in where it looks fine but isn't. I would say my first inclination is that there's something wrong with the hammer and disconnecter not engaging. Let us know if you solve the problem and if you can post some picks looking down into the trigger group. http://gallery.me.com/vvacca#100214 You can't really rule anything out until you figure out what is actually wrong, it just smart debugging, but that said I can't think of a situation where the ammo would be the issue. If you had severely underpowered ammo or a gas flow problem and the gun short stroked or didn't feed the next round I would consider it, but I can't think of a set of circumstances under which the gun has bolt has enough rear movement to eject the spent case a feed a new one and NOT reset the trigger. If the trigger bits don't move, the hammer doesn't all, the firing pin doesn't hit the ammo so the quality of the ammo is not even relevant. My GUESS is that there is something wrong with your trigger group or there is something else going on you haven't told us about yet. Like maybe your thumb is moving the safety around a bit? EDIT: actually I CAN think of an ammo problem, namely if you are blowing out primers and they primers have made their way into your lower. Visually inspect your trigger group and make sure there are no primers stuck in there, there shouldn't be any brass bits in there. My rifle is setup for a righty shooter, but I shoot long guns lefty so my thumb can't be hitting the safety. Quote Share this post Link to post Share on other sites
Vlad G 345 Posted March 27, 2012 Can you get a clearer close of the disconnector hook? Quote Share this post Link to post Share on other sites
MarkWVU02 47 Posted March 27, 2012 Awesome great pics. Just what I wanted. I'll get home around 6 and compare them to my AR. I'll let you know once I check. Quote Share this post Link to post Share on other sites
raz-0 1,259 Posted March 27, 2012 Looking at your pictures, My best guess is that you have MINIMAL disconnector engagement. It also looks like your disconnector is not square on the left/port/driver's side, yet your hammer pics indicate where that is where what engagement you have is happening. When the right state of recoil/vibration/shooter happens, you might be failing to disconnect, but lucky enough to not have the rifle double. Quote Share this post Link to post Share on other sites
PK90 3,573 Posted March 27, 2012 Hammer spring is installed wrong Disregard Quote Share this post Link to post Share on other sites
SW99 2 Posted March 27, 2012 I'll get some more pictures up in an hour or so. The rounds are clambering fine, trigger just seems to lock up after 2-3, 5 shots, then I clear it, and it's fine again for a few more rounds. Quote Share this post Link to post Share on other sites
MarkWVU02 47 Posted March 27, 2012 Try removing the upper and pulling the trigger (making sure to stop the hammer with your finger before it hits the lower or slide release) then reset it. Do it a few times and see if there's ever a time when it fails to reset. I really have a feeling it's the hammer and disconnecter not working together. Quote Share this post Link to post Share on other sites
Vlad G 345 Posted March 27, 2012 Try removing the upper and pulling the trigger (making sure to stop the hammer with your finger before it hits the lower or slide release) then reset it. Do it a few times and see if there's ever a time when it fails to reset. I really have a feeling it's the hammer and disconnecter not working together. And when you do that test, recock the hammer BEFORE you release the trigger, because when the gun does it the odds are you trigger is still back. Quote Share this post Link to post Share on other sites
MarkWVU02 47 Posted March 27, 2012 And when you do that test, recock the hammer BEFORE you release the trigger, because when the gun does it the odds are you trigger is still back. Good call forgot to mention that. Quote Share this post Link to post Share on other sites
SW99 2 Posted March 27, 2012 More pics http://gallery.me.com/vvacca#100222 Quote Share this post Link to post Share on other sites
Vlad G 345 Posted March 27, 2012 Ok I can't tell for sure but I think the last picture confirms what me and raz-0 were worried about, it look like your disconnector is not even, like it has a bevel on the left/port/driver side. From the scratches on your hammer it also looks like it does not engage squarely. If you can take out the disconnector and take some pictures of it by itself on a some sheet of white paper I might be able to see better. Edited to add: the whole disconnector looks to be very rough and poorly finished, though that could be a trick of the light but it looks crummy in multiple pictures. Which brand disconnector is that? Quote Share this post Link to post Share on other sites
SW99 2 Posted March 27, 2012 Ok I can't tell for sure but I think the last picture confirms what me and raz-0 were worried about, it look like your disconnector is not even, like it has a bevel on the left/port/driver side. From the scratches on your hammer it also looks like it does not engage squarely. If you can take out the disconnector and take some pictures of it by itself on a some sheet of white paper I might be able to see better. Edited to add: the whole disconnector looks to be very rough and poorly finished, though that could be a trick of the light but it looks crummy in multiple pictures. Which brand disconnector is that? Is a DSA (dsarms.com). So i did the test in this video (at minute 10:50) which is what you guys were saying to do. When i push the hammer back (still holding the trigger) and let go of the trigger slowly like the guy says in the video, sometimes its getting stuck, and not popping back up slightly like it shows in the video. (at 11:20 in the video) so it seems like this is my problem? Quote Share this post Link to post Share on other sites
SW99 2 Posted March 27, 2012 PM Sent PM returned! Quote Share this post Link to post Share on other sites
alowerlevel 77 Posted March 27, 2012 Yep, sounds like the disconnector isnt releasing the hammer all the time like it should. I would take it apart and look for burrs or anything else that looks out of place on the hammer and disconnector. Quote Share this post Link to post Share on other sites