Not sure if anybody else is moving forward with this project, but I have a minor update. I’ve been holding off on sending my upper for a cut/thread until I had the chokes in hand. They were ordered back on 2/24 with an Availability of “Estimated to ship within 7-16 days”. On 3/9 I got an Update email that said “New estimated ship date of Saturday March 21”. Haven’t heard anything else and sent them an email earlier this week asking for status. No response, but I checked order status online and sometime in the last 2-3 days it’s been updated to and estimated ship date of 4/15/20.
I went back to the thread on AR15 to get the guy’s name that did a pretty detailed write-up. It was Edward Avila...who happens to be the founder of AR15 if you didn’t know. I’d read in another thread that Ed Sr died within the last week or so (no idea if it’s Covid-19 related), but I don’t know if the person posting was Sr or Jr. Either way, the account hasn’t been online since early March.
However, I looked through the write-up and pics and it was mentioned the chokes index off the muzzle instead of the shoulder, which make a little sense. You wouldn’t want a gap between the muzzle and the inner lip of the choke. The factory flash hider appears to be the exact length so that it hits the muzzle and shoulder at the same time.
Here was a pic of the inside of the choke:
And then this pic showed that the choke doesn’t quite come down to the shoulder:
So, I figured if I had the barrel rethreaded to the factory thread length, it would let me use the flash hider or the chokes. If I waited longer and had it thread to be a perfect length for the chokes, the flash hider would hit the shoulder before it hit the muzzle and I’d have a little gap inside that sounds like a bad idea.
If that’s the case, why wait. Just boxed up the upper and created a packing slip. I’ll drop it off tomorrow and ECCO should have it midweek. Hopefully it’s a 1-2 week wait and then I’ll have it back and put it all back together...assuming reassembling the piston upper is as straightforward as disassembling it was.