So I had some parts laying around....
...So I decided to do my first AR9.
First few mags had failures to eject, 1 or 2 about every ten rounds. Ejector position was reasonable, but found the IDL bolt had no insert or o-ring on the extractor. Replaced the extractor spring with a BCM and added the insert, and so far so good! Needs some more rounds to call it absolutely reliable, but a great start!
Recoil feels really good, no worse than a 5.56, and better than my apparently over gassed midlength 16".
So far using 17 and 27 round Magpul, and 31 round SGM mags, no issues on that front.
Lower:
SBR'd Anderson, all milspec
Stern AD9 adapter and flared magwell
KAK mini milspec buffer tube & "micro" buffer (1 Tungsten weight, about 3.3oz)
2 of Blowback9's pinewood derby tungsten weights, about 6oz total
C3Junkie flat wire spring, trimmed until I got bolt lock back
Chopped B5 Bravo stock
DAC ULCG grip
Upper:
AO Precision milspec receiver
Ballistic Advantage 5.5" barrel
KAK flash can
NBS (? I think, cheap one from AR15discounts) 7" handguard
IDL bolt
Milspec charging handle
B5 vert grip and Magpul mlok inserts
Cheap Truglo dot and Amazon "Unity" riser.
These have been on a number of ARs, and are usually placeholders for something better. They just keep ticking, so this might be their permanent home 😆