Sarco list the 308 hammer as different from the 223 hammer. Gun parts list the same hammer for semi auto 308 and 223 Galil's but they list different hammer springs. What could be different about the hammer spring? Time to look at a parts blow-up pic.
A 308 Galil build but on an ORF receiver.
Building a .308 Galil on an ORF receiver - UZI Talk Forums
Upsides on this build: I should have a decent barrel, tightly chambered and headspaced. 1.6mm receiver with the rails tweaked so the bolt carrier has minimal clearance. Hadar stock with a forward anchor under the front trunnion and fully-floated barrel.
Downsides: no side-mount scope bracket possible with Hadar stock. No rear tang to mount a Beryl rail to. No access to the sides to use one of the Chinese "spider" scope mounts. So I need to mount the scope to the top cover or use an RSB and mount the scope to that, like you did. Technically the top cover mount is bad, but it seems to work for the various "Hunter" rifles, and the original Hadars, for that matter.
You mentioned reducing the clearance between the bolt and the carrier to keep it lined up with the bore. I will be looking into that; I guess the first thing to do is make sure the bolt carrier's centerline is the same as the barrel centerline.
Most of the Hunters use screws to anchor their top covers - the screw patterns seemed to vary according to whether they were Finnish, Israeli, or Chinese. Two tabs hanging down at the back and screws going sideways into the receiver was popular with the Finns. Some Chinese rifles had one rear screw on a flange, attaching the cover to the top tang. Other Chinese Hunters had a screw on the front left, going into the RSB. Someone did one with two small screws going into a special rear spring holder; I'm not sure if that was factory or aftermarket. The Hadar didn't use any screws, probably because you'd have to remove the receiver from the stock to get to them. Which isn't an absolute deal-breaker for me, though it'd make cleaning into more work.
I have to make the rear trunnion from scratch since it has to match the angle milled onto the back of the Galil receiver. No big deal there. I have this vague idea of making it taller to provide space to mount a Beryl style rail. I'll probably try just the plain latch-anchored top cover first, though.
Hm, you might be able to increase preload with a standard spring by building up the area of the hammer where the spring touches it. Tou couldn't get a lot by doing that, but it'd be easy to do.
From what he talked about on how he modified the hammer, it sounds like the rear of the bolt sat further back in the .308. He said he took a quarter inch off the front. I think I've read about some guys moving the hammer pin back on conversions.
I found this picture by some lucky b***** who has two Hadar IIs. It's way better than the pictures I took of my stock - you can get a better idea of how sculpted it is. Note the sling swivels, and how the right side is cut away for wrist clearance around the pistol grip. The stock doesn't look nearly so blocky in real life, and it's way more comfortable than it appears.
I also found a picture of a Micro Galil. I think the front sight block/gas block unit is the same between it and the Hadar.
Also take a look at the bolt carrier - I had thought the Hadars used the 45 degree handles, but it looks like they used a stairstep handle. The step to raise it to clear the stock, and sticking out the side instead of up so you wouldn't bump the scope if you had the optional top cover with the scope mount.
Ah! *@&!&!! I just noticed the picture was from "jetskrtal" - one of those is stocks is the one I own now!
Apparently Google doesn't index Uzitalk; that thread doesn't ever come up when I search for Hadar stuff, anyway.
I found another picture, again better than the ones I took. This one shows the "cast" of the Hadar stock well. The centerline of the buttpad is slightly to the left of the centerline of the barrel. Not all rifles have cast; it has gone in and out of fashion over the years.
I may have my Hadar stock back now. My wife saw a picture of a Super Vepr stock, and she now wants one of those instead.
Looking around, it looks like most of the full-stocked Super Veprs have been converted to folding stocks and pistol grips. You'd think the wood stocks would be a glut on the market, but I haven't found any, other than one on Gunbroker the seller withdrew before the end of bidding.
Looks like the Super Vepr has a screw going up from the bottom into the front trunnion like the Hadar, plus another one at or near the gas block. There doesn't look like enough room for a buttstock screw like the Hadar, so I'm guessing the pistol grip screw does all the work in the back.