1st off I'm NO gunsmith! The AR 9 9MM a friend & I put together on Christmas is giving me issues with 'misfired' cartridges. 1st outing last Saturday, I fired a total of about 200 rounds. The 1st 90 rounds (50 rounds Magtec 115gr fmj & then 40 rounds of Aguilla 124gr fmj) functioned flawlessly. The next 110 rounds (60 rounds of same Aguilla 124gr fmj & 50 rounds of Federal 115gr fmj) had 12 rounds that did not go boom! Appears to be much lighter strikes on the misfired. Reloaded all the misfired into the mag again, & again, no boom. Fed those into my Sig p938 & every single one fired perfectly. I originally believed the filthy firing Magtech may have gummed up things causing these issues. Took the pistol home & preformed a good cleaning. Went back out today with a clean gun and Federal ammo. 1st 2 shot were good, 3rd round went click only, didn't fire. Out of 80 rounds, 12 didn't fire. Refilled mag with those 12, 4 did go off the 2nd time around, the other 8 did not. Had a box of Tula steel case 115gr fmj( which I don't like to use) & figured I'd try, just to have another brand/batch for comparison. Out of 15 rounds loaded of the Tula, only 4 fired. 11 did not. I am thinking it's an ammo or debris issue. I've checked FP protrusion with & without FP spring. Also checked FP spring was collapsing properly & not buckling or binding. So, what else should I look at? Hammer/trigger spring? Headspace/chamber depth? Thanks in advance for any advice & suggestions.
AR 9 pistol light strikes, sporadic
- Thread starter LonewolfMcquade
- Start date
The 3 setting on Black strip on the right fired fine, notice the deeper primer strikes. The 2 on the left, lighter strikes, did not go off.
Bcg
Dusty Stevens
Shiner
Looks like headspace to me. Put one that had the light strike in the chamber and measure how far it sticks out compared to one thats been fired
Is it more possible that I am a complete dumba$$? I just took side by side pics with my ar15....
The "problem child" is on the left, the properly ASSEMBLED AR15 is on the right! I'm just a wee bit embarrassed at the moment.... the hammer spring is upside down in the pistol on the left.
Dusty Stevens
Shiner
Everybody makes mistakes. Glad you figured it out easily enough!!
Don't they recommend a different hammer for 9mm vs a regular AR?
Thanks. Plain stupidity on my part for not double checking my own work. The hammer has double the tension & hitting force now! Bill Engval comes to mind...
My Sharps receiver. is designed to be put together with a mil spec hammer. & a 9mm BCG
Not a dumba$$, very smartA$$. You found, diagnose and repaired the problem.
True, but I'll still be checking my work boots in the morning to make sure they're on the right feet...
Since You had a dumbass moment, Ill Just say it cause every dumbass blames every ar problem on it, Its probably overgassed, nevermind its recoil operated and something propbably got put together wrong, spend lots of money on fancy ass springs and buffers and gas blocks, then go flip your hammer spring around.
FYI I just fixed this same problem for someone that had his gun/parts kit put together by an "expert". Told him he needed to change out his buffer spring it was too weak and is overgassed. Also put a damn O ring under the extractor.
Glad you figured it out.
FYI I just fixed this same problem for someone that had his gun/parts kit put together by an "expert". Told him he needed to change out his buffer spring it was too weak and is overgassed. Also put a damn O ring under the extractor.
Glad you figured it out.
Generally, you use mil-spec springs on a 9mm AR and I have gone a little lighter on mine. The buffer and spring need to be changed to cycle properly. Lots of fun and inexpensive to shoot. Everybody should have at least one AR in 9mm!
skeeljc
Gold $$ Contributor
9mm AR's are known for beating triggers to death. There are not many triggers that will survive long term in a 9mm AR. HyperFire is one that does.
I shoot Steel Challenge with my AR-9. I run 124 grain Berry's plated bullets at 980 fps out of a 16" barrel. Some guys slow them down more than that. Factory 9mm ammo will come out of a 16" barrel at 1200 fps to 1400 fps.
I shoot Steel Challenge with my AR-9. I run 124 grain Berry's plated bullets at 980 fps out of a 16" barrel. Some guys slow them down more than that. Factory 9mm ammo will come out of a 16" barrel at 1200 fps to 1400 fps.
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Fast14riot
Gold $$ Contributor
9mm AR's are known for beating triggers to death. There are not many triggers that will survive long term in a 9mm AR. HyperFire is one that does.
I shoot Steel Challenge with my AR-9. I run 124 grain Berry's plated bullets at 980 fps out of a 16" barrel. Some guys slow them down more than that. Factory 9mm ammo will come out of a 16" barrel at 1200 fps to 1400 fps.
Ooo, that looks like fun! Details on your build, please... I need a 9mm AR in my life!
skeeljc
Gold $$ Contributor
PSA 9mm Dedicated Lower - Colt Pattern (SMG mags)
Aero Precision Slick Side Upper (converted to LH active charger)
Faxon 16" barrel - 9mm
PSA G-9 Hybrid Bolt
Blitzkrieg Hydraulic Buffer with JP AR-15 carbine recoil spring
Taccom Carbon Fiber Handguard
Hyperfire 24C Competition Trigger
Yankee Hill Machine Flash Hider
Sanders Armory Tactical Stock
C-More Red Dot
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