I've finally gotten around to finishing my Matrix 7.62 from last years GB. During a function check I noticed the bcg isn't going into full battery. Upon pulling the trigger the bcg moves roughly 1/4" forward. Also if I cycle the bcg while still compressing the trigger (to simulate live fire) the bcg will not reset the trigger. However, cycling the bcg with finger off the trigger will charge the rifle. I've also seen the trigger go dead just from the buffer putting pressure on the carrier. Remove the buffer/ spring and trigger functions. This happened a few times.
The rifle is setup with correct Armalite A pattern LPK, standard mil. spec. trigger, Armalite bcg and 18" Armalite barrel (was 20" originally) with Armalite GB and tube. Using a standard carbine stock with carbine spring and buffer.
Here she be
What has been tried so far:
1. Removed the carbine stock and replaced with Ar10 A2 rifle setup
2. Put my Armalite upper on the Matrix lower: Same bcg 1/4" movement.
3. Removed mil. spec. trigger and replaced with a Timney
4. Removed the barrel assembly and re-installed.
5. Removed the bolt and checked carrier operation: same movement
What I have noticed:
1. Front pin fits very tight, stupidly tight.
2. Finish on the new charging handle is getting jacked up. Not smoothly operating.
3. There is a gouge in the cam pin cutout of the upper receiver (see pic).
4. There's more of a gap between the charging handle and the front of the receiver than on the Armalite (see pic).
5. There's a new mark on bottom of the bcg below the firing pin (the first spot to contact the hammer upon cycling).
It should be mentioned this is not a new barrel or bcg. These were part of a working setup from my Armalite before boredom said needlessly waste cash and change some stuff.
Definitely need help from those smarter than I. I'll be seeing a buddy Tuesday. His Matrix is 100% functional so I plan on a mix and match session. Because both uppers exhibited the same issues I'm leaning towards something going on with the lower. Unfortunately I can put my Armalite upper on the Matrix but not the Matrix on the Armalite due to different size bolt catches (Ar10B pattern).
The rifle is setup with correct Armalite A pattern LPK, standard mil. spec. trigger, Armalite bcg and 18" Armalite barrel (was 20" originally) with Armalite GB and tube. Using a standard carbine stock with carbine spring and buffer.
Here she be
What has been tried so far:
1. Removed the carbine stock and replaced with Ar10 A2 rifle setup
2. Put my Armalite upper on the Matrix lower: Same bcg 1/4" movement.
3. Removed mil. spec. trigger and replaced with a Timney
4. Removed the barrel assembly and re-installed.
5. Removed the bolt and checked carrier operation: same movement
What I have noticed:
1. Front pin fits very tight, stupidly tight.
2. Finish on the new charging handle is getting jacked up. Not smoothly operating.
3. There is a gouge in the cam pin cutout of the upper receiver (see pic).
4. There's more of a gap between the charging handle and the front of the receiver than on the Armalite (see pic).
5. There's a new mark on bottom of the bcg below the firing pin (the first spot to contact the hammer upon cycling).
It should be mentioned this is not a new barrel or bcg. These were part of a working setup from my Armalite before boredom said needlessly waste cash and change some stuff.
Definitely need help from those smarter than I. I'll be seeing a buddy Tuesday. His Matrix is 100% functional so I plan on a mix and match session. Because both uppers exhibited the same issues I'm leaning towards something going on with the lower. Unfortunately I can put my Armalite upper on the Matrix but not the Matrix on the Armalite due to different size bolt catches (Ar10B pattern).
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