New 9mm AR problems...Suggestions?

[ryee30]

Hi,

I just went to the range with my new 9mm AR. Needless to say, the experience was a bit disapointing.

The first 5 rounds were good, then I started to experience stovepipes, failure to feed. Sometimes both at the same time.

I'm using the 32 rd C-Products mags that I pinned for 10 rd. I was extra careful to make sure that the pin did not interfere with the spring. This is my main suspect, but I'm not sure. When racking the bolt, the spring also feels WAY more stiff than my standard AR.

My build consists of:

DDLES lower
VLTOR upper
RRA 9mm buffer
standard AR buffer spring
Spikes 9mm buffer stop
RRA 9mm barrel
Spikes 9mm bolt

Any suggestions? I've love to try Metalform mags, but don't know where to find them in CA.

[Dirtbiker]

Pick up some UZI mag kits and mod them to work in your rifle. All they need is a mag release cut out added to them (plus limited to 10 rounds)

[jchen76@gmail.com]

Do you a 9mm magwell adapter or dedicated 9mm lower?

If dedicated, it's probably magazine issue.

If you have magewell adapter, may have to adjust ever so slightly and test.

[tacticalcity]

Also could be you not putting enough shoulder into it. The rifle needs to have a firm support behind it so that when the bolt comes back to load the next round the rifle is not moving back with it. So lean into it and tighten up those shoulder/chest muscles so you have a nice solid foundation preventing it from recoiling back too much.

After you confirm it is not you, not the adapter, not the magazines, look into making sure you have the correct springs and correct buffer for the type of ammo you are using. if those are incorrect they can mess up the timing and result in the problems you are having.

Just so you know, this is normal learning curve stuff. You'll get her ironed out.

[ryee30]

I will keep the shoulder/chest in mind next time I go.

As far as the recoil setup goes, I have the RRA 9mm buffer, a Spike's buffer spacer.

Is there a different spring I should use?

[crazychinaman]

Doess your bolt have the cut out for the hammer or Are using a 9mm hammer.? Also try plastic /poly pro mags,They work great in mine.Also what kind of ammo.It does not like hollow points that have flat tip and weak ammo.

[ryee30]

I have the 9mm bolt from Spike's that is suppose to use the standard AR hammer.

No hollow points, just standard Remington 9mm 115 grain.

[bwiese]

Try 147gr - "Uzi black tip".

I had all sorts of problems with my Colt 9mm AR upper when I was using WWB and PMC 115gr ammo. A bit anemic.

Once I ran the hotter ammo - and this included 124gr as well - the gun ran fine.

[shark92651]

What kind of hammer are you using? Is your RRA bolt carrier ramped? I just completed my DDLES build last week and it is running flawlessly using cheap 115gr 9mm bulk ammo and riveted metalform mags. My BCG is a ramped Spikes, a RRA 9mm buffer (no buffer stop though).

[challenger]

You're using a Spikes buffer spacer are you using a rifle length stock? If not pull the spacer out and rack it again, might be better.

[ryee30]

@shark92651 - I have a Spikes bolt carrier and it is ramped. I also have a Spikes nickel plated hammer.

@challenger - I'm using using the spacer with the carbine length buffer tube. Which I thought was what I needed to do in order to not break my bolt catch.

I wonder if it will be better with a lighter standard AR buffer?

[Zombieguns]

I use the same Cproduct mags in my RRA/Doublestar 9mm carbine for the FTF it could be that the mag is not seated all th way they have a hard time seating on a closed bolt, and on the stove pipeing is the buffer spring new or used from 223 rifle? If new could need breaking in or you can run hotter loads in it to break it in quiker, I run .147gr lead cast flat point subsonics in mine and they run flawless in my carbine or try .124gr rounds in it should run well, these are just things to try hope they help.

[challenger]

The spacer is intended for an A1/A2 buffer tube and a carbine buffer. I'm pretty sure that's the problem. http://www.spikestactical.com/new/z/...cer-p-709.html

[ryee30]

I'm actually using this spacer: http://www.spikestactical.com/new/z/...9mm-p-174.html

[Don the savage]

9mm ARs are ammo sensitive, what are you shooting? As bwiese said low power ammo is the devil Bobby bouche.