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11/3/2014 9:48:49 PM EDT
So my newly built upper will run fine with Tula 115gr, and ZQI 123gr. However, I am having light primer strikes and failure to fire with Winchester white box 115gr.
It is very weird that the cheap ammo works. I ran the WWB through my glock and did not have any issue there. I started with a 2 stage KAC trigger had the issues and switched to a single stage milspec CMMG (I think). Still had the same issues so changed back to the KAC.

Relevant Parts used.
JP bolt
Green mountain barrel
Slash heavy buffer and wolf spring
DDLES glock lower- BHO does not work even after bending tab down- hope the fix for this happens soon!
KAC 2 stage trigger

I have inspected and cleaned and will try some more types of ammo later in the week. I am rather stumped. I did email JP and have not heard back from them yet...

Any ideas?
Thanks for your reply!
11/4/2014 8:44:44 AM EDT
[#1]
I have a DDLES Glock lower, JP bolt, Slash heavy buffer & spring, Mas Defense 8 in barrel with a ALG-ACT trigger and it works perfectly. I'm running an Octane 45 suppressor use 135 and 147 gr loads. I tried it with factory 115 when I first tested it and it worked fine with that too.
11/4/2014 8:48:14 AM EDT
[#2]
My thoughts are it is either ammo related (primer seated too deeply in the brass), to much spring tension in the firing pin return spring or possibly the hammer not being heavy enough....

Thanks for the reply batman. I may have to try one more trigger and if no improvement then send the bolt out to be looked at...
11/4/2014 10:34:52 AM EDT
[#3]
Try swapping out for a milspec trigger group with full power springs and go from there. With builds, you want to start with a baseline and change from there to ensure reliability.
11/4/2014 7:09:33 PM EDT
[#4]
Mil spec trigger was tried already.
Talked with JP enterprises and have some ideas to try at the next range trip. Customer service was excellent and they will look at the bolt and upper if I do not get it figured out.

They did say they use reduced power hammer springs in their complete 9mm builds and have not had any issues. It could be a chamber issue or an extractor issue.
Will update.

Thanks!
11/7/2014 12:10:33 AM EDT
[#5]
1. Check chamber depth.
2. Try a new bolt.
11/7/2014 8:58:08 PM EDT
[#6]
Worked flawlessly yesterday!
KAC 2 stage back in.
Cleaned and well lubed.
Different box of WWB and 6 other brands.
Cycled all 7 different brands without issue.

BHO still does not work but I'm confident a fix is on the way...

Only thing that changed is a few dry fire sessions and a cleaning session...needless to say I'm very pleased.
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