Still saving money for the HMG flat and weldment kit...hopefully by the time I can save it up they still have some. If not, well...I have made dies before.

Anyway, what I want out of my L kit is a "DMR" style rifle. Think Cetme L meets PSG-1. We'll see if I actually make it happen or if I just build a standard L, but here is the "desirable" list.

-18" free-floating barrel
-Integral bipod
-Birdcage style flash hider/muzzle device
-Removable optic
-Good iron sights
-400yd effective shot range
-6.8SPC chambering

Here's the "obstacle list".

-It's roller delayed.
-Front sight base is pinned to barrel
-Handguard pinned to FSB
-Sights sit very tall on receiver
-.223 is boring, but cheap and barrels are readily available.
-6.8SPC is neat, but fluted chamber barrels are only made from the purest unobtanium.

Now, I don't get to go shoot as often as I'd like these days-I maintain my range membership but maybe 10 days a year do I get to actually go shoot. My range has a 385yd limit, that's the longest target frame distance-and it's uphill. I *love* being able to go out and tag the 4" bell at 385 with most of my rifles.

So, since I don't have the receiver bits yet, but I already stripped down the old receiver bits following the HMG instructions, I thought I'd look at the free-floating barrel issue. This is the steel handguard liner, cocking tube, and front sight base all layed out together in roughly the positions they will be in:



and the disassembled view: (We prefer to not use the term "exploded view" when dealing with firearms, gas appliances, or auto engines...)



The steel handguard liner didn't want to lay still for the photo. Drill bit helped.

I am thinking maybe weld or pin the cocking tube to the front sight base, and bore the barrel ring slightly larger or turn the barrel slightly smaller (probably turn the barrel!) to provide for the free-float feature. The cocking tube is a substantial bit of steel, but I think it will need some help from the handguard-maybe a pin through at the bottom of the front trunnion? (I'd have to weld an extension block to the front trunnion to hold the pin, but that's nothing too difficult.

Another thing is the 922r parts count-would anyone else be interested in some forearms, pistol grips, and maybe buttstocks? I am planning to have a go at molding some, to get my US parts count up. I prefer to stay under the "10" imported parts by at least two. Also, the PSG-1 is wildly different in those areas, so why shouldn't mine be? Even if all I do is mold them in some color other than dirty green...Personally I like the duracoat #80 "HK Blue/Grey" color...

As for the barrel, there's no way like the right way to cut chamber flutes. My test Method #1 was a plastic chamber mold plug, with grooves carved in to lay a brass wire, an o-ring seal on the freebore area to protect the rifling, and a bit of plastic tubing to provide a "flow-through" style flush and electrochemical machining should be the way to go. The only issue is, my test piece didn't cut the flute deep enough-I haven't provided a way to "advance" the brass wire "cutter" to keep cutting. Finish was excellent, but the depth of the cut was only 0.008". I am afraid that unless I can keep the gap to a controlled size the flute width will be hard to control. Method #2 of cutting the flutes was to paint the chamber, and then scrape out the flute area to bare steel again. Once the 12 flutes were scraped down to bare steel, a cotton plug was used as the electrode, and a steady stream of electrolyte was used to keep the plug wet and cooled. I was able to etch the flutes to 0.01" deep before undercutting started to become very evident. Maybe rough in with the etching method, then finish up with files? Not sure.

Anyone else play with the electrochemical method to cut the flutes?