Brand new AR-15, Having Issues

[Battaglia1911]

So I took my brand new MP 15 to the range today. I loaded a pre ban mag with pmc and started shooting. The first few rounds were fine, then on the next round I pulled the trigger and nothing happened. I cleared that round, chambered the next and it fired a few times, then the same issue. I thought it might the mags so I tried a friend's 20 rounder and ran into the same issue after firing a few shots. This was the first time firing this rifle, and I did clean it before hand. Seeing as I'm new to owning this rifle I'm wondering if anyone had any ideas what the issue could be?

 

[Gammon]

Just a guess, but the bolt might not be going completely into battery. This would result in a light hit on the primer. Another possibility could be a defective firing pin, but I think a tight fit on the new gun is more likely. Hand cycle the bolt and see if it hesitates upon going into battery. I would also disassemble the bolt carrier group, clean it and lube generously.

 

[noddaduma]

Lube BCG as above. Could also be that your rifle didn't like either mag. You may want to try a newer mag like a Magpul or something.

 

[Another_David]

clean and lube then:

 

[fencer]

Lube that sucker like a Ptown queen

 

[Battaglia1911]

Thanks everyone for the tips, I'll do what was recommended then test her out when I get a chance.

Sent from my HTC One using Tapatalk 2

 

[Artifact]

Did you try different ammo?

 

[Battaglia1911]

Did you try different ammo?

Yea tried different ammo and different mags. That same ammo worked fine in my friends mp 15t. One thing I didn't do was try a factory ten rounder because I didn't bring them with me.

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[bdb]

I was having a fair number of duds which I now attribute to a light strike. I was also having my trigger pin walking it's way out after 50 rounds or so. After some research I found out that the hammer spring was in wrong, basically backwards. ar15.com had some threads on it being a fairly common issue with us noobs building AR's as the spring looks mostly right and passes all the function tests. It still fires fine but the spring legs don't lock the trigger pin since the spring is backwards. I did notice there is now more tension on the hammer than when the spring was backwards. My hope is my light strike issues go away now that I have fixed it and noticeably more tension on the hammer spring. It may be of no help to you but thought I would pass it along.

 

[Battaglia1911]

I was having a fair number of duds which I now attribute to a light strike. I was also having my trigger pin walking it's way out after 50 rounds or so. After some research I found out that the hammer spring was in wrong, basically backwards. ar15.com had some threads on it being a fairly common issue with us noobs building AR's as the spring looks mostly right and passes all the function tests. It still fires fine but the spring legs don't lock the trigger pin since the spring is backwards. I did notice there is now more tension on the hammer than when the spring was backwards. My hope is my light strike issues go away now that I have fixed it and noticeably more tension on the hammer spring. It may be of no help to you but thought I would pass it along.

Though I didn't build this particular AR, I will keep this in mind once I build my own. Thanks.

 

[mac1911]

1. Always clean a new firearm. Most manufactures apply a protective substance for rust and corrosion. It is far from lube.

Tech Notes there is a ton of info here from malfunction diagnostics to cleaning,lube and ammo tips.