Need help with Sun Devil SD308

[C172 Heavy]

Long, long ago. In the before time............

I bought a stripped Sun Devil SD308 (AR308) set. This was back in October of 2016. I'm just getting around to build it up and have run into a problem. I'm using one of the CDNN AR308 LPKs. The front pivot pin is mostly wrong. It's too long on the head side, too short on the tail side, and the detent does not lock into the "closed" side detent hole. The takedown pin is mostly ok but the "tail" side is just a hair long and hangs up on the upper receiver takedown stud.

Anybody have any idea what brand of takedown/pivot pins to use? I can make the takedown one work with some filing. With a lathe I could get the pivot one to work but it'd just be easier to find the right pins. Sun Devil went out of business so I can't reach out to them. Hopefully someone here built an SD308 and knows how to fix this issue. Thanks.

 

[Winmagbill]

It was the best of times, it was the worst of times. Specifically 13 years ago..

Sun Devil MFG has begun production of DPMS pattern 308 AR receivers.

Here is a quote directly from Sun Devil MFG

We are machining the .308 lowers now. We should have the uppers ready to machine in 60 to 90 days. The MSRP is $249.95 for the lower. They look very similar to our AR15 receivers. They are DPMS compatible and they also have the tension screw.

 

[Abbey]

I had some issues with SD15 receivers being out of spec back in the day. I even took them in to the shop and their pin gauge didn't go. The owner was pretty pissed that his machinist gauged them in front of me after he just got done telling me that my parts kit must have been out of spec.

So my issue was basically tolerance stacking. I forget which part I was having trouble with but they gave me a few extra pins (maybe DPMS?) that fit in their out of tolerance lower. So you may just need to try a couple different brands of parts.

 

[C172 Heavy]

I think the LPK I got was a leftover from Bushmaster. I'm just going to try and source some pins and hope for the best.

 

[BigNate]

I know that I'm late to the party - but - if you can throw a set of calipers on it and see what dimensions are that would help? I bought a pivot and takedown pin from S2 Tactical (43rd Ave and Bell) a few weeks ago for my Aero M5 build. The pivot pin was too short (well - it worked - but it didn't protrude out of the far side of the lower - so I had to use a tool to pop it. I ordered the "correct" length pivot length pin from Aero and pulled the other one out.

So - you might find what you need at S2 (they sold me a few other parts that saved me waiting for things to ship) and / or - if the one that I pulled will work for you I'm happy to get it to you.

 

[C172 Heavy]

BigNate. I need a pin with a shank length of 1.5" and the detent dimple needs to be .110" from the shoulder.

 

[BigNate]

Here's the pin...



I think I had misread your post previously. I read it as 1.10" to the dimple. I'd bet that if I put calipers back on it when I get home, it is 0.110 to the edge of the detent cut...