I've been working on the same project...an accurate AR180B suitable for varmints. I have no interest in a commie-fighting rifle, just an accurate varmint gun. Out of the box, mine wasn't. Mind you, the 12 pound trigger pull didn't help. That was the first thing I fixed. I took it down to 4 lbs without buying any aftermarket parts. I might go that route yet.
Then I sawed the rear sight off, milled it flat and made a rail that I screwed down on top of the upper. I mounted a scope (solid and low) on that and then started working on handloads.
I found it liked Hornady 60gr V-Max the best, shooting 5 rd groups of around 1.5" (too often they were larger) when I crossed my fingers just right. But it wasn't consistent. I shot a bunch of coyotes, including three in a row at 200 yards with that load and then the hinge broke.
Wolverine Supplies replaced the lower quicker than I could say "mangy coyote" and I was back in business. But I didn't want to break another hinge so I made a recoil lug from a piece of aluminum bar stock, attaching it to the bottom rear of the upper and "glassed" it into a convenient depression in the lower, right above the pistol grip. It's invisible from the outside and really solidifies the mating of the upper and lower. I've put 200 rds through it since then and it has improved accuracy and consistency. If it will improve longevity remains to be seen, but I believe the lug will do that.
However, it still isn't a sub MOA gun. My best 5 shot group after the lug installation is 1 1/8". I never came close to that before. However, it's still not there. If I could get CONSISTENT groups of that size I'd be happy. I've shot several more coyotes with it since doing that work, including a one shot kill on a fox at over 280 lasered yards.
I haven't done enough range work to be convinced of its consistency yet. That's important to me. It needs to be able to hold point of impact and shoot well every time I take it out and shoot it on paper. In the past it has had good days and bad days.
Random Comments:
- For my purposes I really, really like the light weight of the 180B and I much prefer the AR-like handling over the Ruger Mini-14.
- The gun is under-built, especially the hinge.
- With all the work I've done to mine, I think I'm now getting close to what I want in a semi-auto varmint rifle. That means it's light in weight and accurate enough for bigger varmints, like coyotes. It's not accurate enough for gophers, but I don't use it for that.
- If you have to pay to get this kind of work done, the gun might not be for you.
- how many shots are those sub 1" groups you've heard about based on...3?
I've had sub 1/2 inch 3 shot groups with mine, but the other 2 made for a
4inch group. Personally, I don't think three shot groups are worth a pinch of coyote poop.
- If someone has an honest to God, box-stock, five shot group, consistent sub MOA AR180B, they are incredibly lucky. I wish it was me.
-Is mine for sale? No way. I think it has potential and I'm not done with it yet. I just might rebarrel with a quality barrel before I'm done.
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