OSA - 17 Design Lowers - Completed Builds Thread

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thor447

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Ok, first build complete! Will be taking it to the range tomorrow evening to test it out.

PCC - 9mm
17D billet lower
9mm billet upper (bought locally from another OSA member)
Stern Defense Barrel - 16.1" 1:10
Bolt - SD BU9 NiB ECHO
Stern Defense Mag Adapter - MAG-AD9
CMC 3.5lb single stage flat trigger with anti-walk pin set
Comp - SD CB9 MOD1
Buffer - H3
Buffer Spring - Wolff carbine spring
Hogue grip and stock
Vltor buffer tube
Sig Romeo 5 red dot

My one concern on this build was the amount of bolt travel past the bolt stop. I've heard of PCC's breaking the bolt stop because that bolt gets a running start then smashes into the stop, breaking it. I put a stack of quarters in the buffer tube and shortened the amount of bolt travel so it only goes about 1/4" past the bolt stop. When test firing tomorrow I might need to adjust the spacer length to get it dialed in. For now though, she's assembled.

f1.JPG


f2.JPG


f3.JPG


I got so excited I took the pictures before cleaning it after assembly!
 
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undeg01

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Tell us about that bad boy...
It is a 17 Design lower but pre-OSA group buy.

Barrel is 10” chambered in 223 Wylde. DPMS LPK with JP enhanced spring kit and polished trigger. Burris TAC-30. Running a Thunderbeast suppressor. I can remove the suppressor and fold it to fit in a standard backpack.
 

okierider

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Picked up my lowers and have one assembled. But now I am waiting on some trigger springs. Forgot that I had installed some MCarbo springs to get the 4lb trigger on the Grendel build so have them headed this way!!
 
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