PinaKaleada
CGN Regular
- Location
- South of most
Isn’t it normal for the cam pin to take a chunk out of the side of the cam box before it “stabalizes”?
Modern Sporter builds Q&A
- Thread starter alberta tactical rifle
- Start date
Isn’t it normal for the cam pin to take a chunk out of the side of the cam box before it “stabalizes”?
Yes, cam pin wear on the upper is 100% normal.
XperienceDUDE
CGN Regular
- Location
- Eastern Canada
Finally got around to filing down the rear adjustment screw housing on my TriggerTech adjustable and with the KNS takedown pin it works 100% no issues getting the upper and lower to mate now. I filed down the adjustment screw housing so it was almost flush with the rest of the trigger body, and I kept the adjustment screw out (no issues there either when firing).
Took it out to the range today as well for the first time. Pleasantly surprised I didn't have any gas block issues or have to make any adjustments to it.
Is there still rattling between the upper and lower using the KNS Rear takedown pin ?
Finally got around to filing down the rear adjustment screw housing on my TriggerTech adjustable and with the KNS takedown pin it works 100% no issues getting the upper and lower to mate now. I filed down the adjustment screw housing so it was almost flush with the rest of the trigger body, and I kept the adjustment screw out (no issues there either when firing).
Took it out to the range today as well for the first time. Pleasantly surprised I didn't have any gas block issues or have to make any adjustments to it.
Great looking setup.
On my other AR-15s it didn't.
- Location
- Saskatchewan
Honestly I’m not sure what the issue was. But ATRS has confirmed the FA uppers and second run of SS next spring will have the “standard” openings as apprised to the oversized openings on the first run of SS uppers.
Since I’ve only held one slick side that was already assembled I can’t say I saw any issues.
Last edited:
- Location
- Red Deer, Alberta
I had the rear pin modification done to my MS lower. $50 at ATRS. It now uses a normal rear pin and my Geissele High Speed National Match fit without any modifications. Call Shaun at ATRS, he dealt with my lower, he'll sort you out.
XperienceDUDE
CGN Regular
- Location
- Eastern Canada
Tell us more about that mod please
- Location
- Red Deer, Alberta
hook on upper as it left ATRS, no modifications.
Contact Shaun at ATRS, he'll explain what needs to be done.
Attachments
You would have to mill the front of your lower receiver to do that.
onetwentyish
CGN Ultra frequent flyer
- Location
- East Central AB (AKA Northern Texas)
Negative with a BCG installed. The Modern series has more material on the lower and less length on the upper where the 2 meet at the rear. You will notice an 1/8 - 1/4" of the BCG protrudes from the rear of the upper when split, this means the upper can not hinge open on the front pivot pin with the BCG istalled as the rear of the BCG would still be inside the lower.
- Location
- Red Deer, Alberta
I have not fired a round out of it, as I got called back to work earlier than expected. And I'm on a boat in middle of the ocean now for another 3 weeks. It passed dry fire function testing fine. I had this exact barrel, BCG & trigger in my Maccabee SLR previously and it functioned fine. I do not see how it could have issues in the MS.
I'm having an extremely difficult time getting mine to cycle. Rifle length gas, carbine buffer (2.9oz) and carbine tube, Superlative Arms adjustable gas block. It's acting like it's undergassed no matter what I set the gas block to, I've made sure the port on it is aligned with the barrel port.
Is there anyone with this combination that's had success?
Is there anyone with this combination that's had success?
You might have to pin gauge the barrel gas port, I don't recall the size but I'm sure Google can get you that.
Also if you take the gas block off again you should see the black ring around the port and whether it was centered.
Maybe check the gas tube length.
Did you check the gas block adjustment when it was off the barrel to see if it opened all the way? I haven't used that particular gas block, just Odin adjustable.
Is it ejecting at all? Sending the bolt back at all?
What barrel?
What BCG?
Also if you take the gas block off again you should see the black ring around the port and whether it was centered.
Maybe check the gas tube length.
Did you check the gas block adjustment when it was off the barrel to see if it opened all the way? I haven't used that particular gas block, just Odin adjustable.
Is it ejecting at all? Sending the bolt back at all?
What barrel?
What BCG?
The superlative arms gas blocks need to be set up just right. Make sure you follow the instructions to the word. I had a hard time setting mine up until I read the instructions and re read it everytime I adjusted it. I thought it was fully on and it was closed right of and made me panic the first few shots as they wouldnt cycle at all.
