"Long Action" Semi-Auto Rifles - What's the consensus?

I really like my NEMO Omen and it will join me on an elk hunt this fall/winter. It's doesn't join me on my typical backcountry hunts here in Idaho, where weight is the primary motivation. It's an oz is lbs issue when packing it in. It's still well under 16lbs configured, but I'm not humping it 30 miles, at altitude, in the frank church. It's accurate, soft shooting for it's caliber and has been 100% reliable.

Why...because I can, and frankly got tired of the fuds telling me I shouldn't be using a weapon like that to hunt with. Fast forward and I've been in the field taking game with an FN SCAR 17S, and AR chambered in 6 ARC and now the Omen.

Side note for OP. A good number of NEMO Omen rifles enter the foreign military sales arena, go overseas to other friendly nations, to dissuade/control bad guy populations. They are no doubt better suited for that and competition where timed follow up shots matter. They are a bit niche in the US buyers market due to cost but scratch an itch for a long action shooter that has to jump to a .50BMG if they want to get into a reliable well supported platform. As others have stated, many rifles on the market targeting hunters but not many in large frame AR community that have been selling, supported and still going strong years later.

NEMO Omen circa 2013
NEMO Omen Unicorn.jpg
 
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I am interested to hear the situation where a follow-up shot is needed, from a 300 Winchester Magnum, and a bolt-action speed follow-up shot is too slow.
At a Rifle Dynamics Match at Blue Steel range in NM, I believe in 2017 Falkor had a demo rifle on the line before the match. The rep got behind the 300 WM and shot approximately 2" group at 300 yards in about 3 seconds. They offered me and my buddy the opportunity to shoot it. I got behind the rifle with bipod and rear bag and replicated the Falkor reps string of fire and accuracy. Then my buddy did the same thing with the same rifle. The Falkor rifle isn't a joke.
 
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Not an expert by any means but based on what I am learning (you probably already know all this...) one of the major challenges with these rifles, especially with high-recoil calibers like .300 WM, is managing that recoil. Semi-autos are more likely to have more pronounced muzzle rise and less stable follow-up shots compared to bolt-actions. Manufacturers are addressing or at least trying to address this with heavier and more advanced muzzle brakes, which significantly reduce recoil, but I would imagine that it still takes some practice to control follow-up shots effectively at long distances. I have a vested interest since I am basically trying to use my new HK 762A4 for a similar application....currently a safe queen.
When shooting a Falkor 300 WM with 190 Fed Match there was very little recoil.
 
I really like my NEMO Omen and it will join me on an elk hunt this fall/winter. It's doesn't join me on my typical backcountry hunts here in Idaho, where weight is the primary motivation. It's an oz is lbs issue when packing it in. It's still well under 16lbs configured, but I'm not humping it 30 miles, at altitude, in the frank church. It's accurate, soft shooting for it's caliber and has been 100% reliable.

Why...because I can, and frankly got tired of the fuds telling me I shouldn't be using a weapon like that to hunt with. Fast forward and I've been in the field taking game with an FN SCAR 17S, and AR chambered in 6 ARC and now the Omen.

Side note for OP. A good number of NEMO Omen rifles enter the foreign military sales arena, go overseas to other friendly nations, to dissuade/control bad guy populations. They are no doubt better suited for that and competition where timed follow up shots matter. They are a bit niche in the US buyers market due to cost but scratch an itch for a long action shooter that has to jump to a .50BMG if they want to get into a reliable well supported platform. As others have stated, many rifles on the market targeting hunters but not many in large frame AR community that have been selling, supported and still going strong years later.

NEMO Omen circa 2013
View attachment 8643708
Does the Nemo Omen tear up brass?
 
I've had no issues with base, pocket primer or rim on my factory loads. If you hand roll them, and they are hot, you'll start to see the typical pressure signs associated with those cases regardless of what you're feeding them in.
What velocities are you getting with factory ammo?
 
How far away was your furthest kill with the 6 ARC?
Late season Nebraska hunt harvested two white tail does. Longest shot was at 187 yards. Link to thread below.


I'll have to search through my field book to see what velocities I'm getting out of the NEMO. I'm shooting a Recon now, 18" barrel, so no doubt I'm loosing a little velocity out of the magnum cartridge. That rifle is much easier to maneuver, and carry, at that length, especially suppressed. Side note that I'm using a HUXWRX 762 flow and it has performed flawlessly on all my gas guns. Probably a little louder than a typical baffled can but the flow-through reduces increased bolt carrier group velocities seen with other suppressors and some gas guns are known to be very finicky when suppressed.
 
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Reliability, cycling, etc., really depends on the builder attention to detail and, of course, quality parts. Fit and finish details - tolerances, truing, lapping, gas adjustment, recoil weights, etc., are important.
 
Yeah. As far as GLFA goes...the chamber in my 308 looks pretty rough. Im having a tough time with stuck cases and torn rims
 

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Yeah. As far as GLFA goes...the chamber in my 308 looks pretty rough. Im having a tough time with stuck cases and torn rims
Oof…those are chamber pics?

Did you install an AGB on yours yet?

I’m pouring the coals to my 300 Win Mag, but I’ve put an AGB on mine.

How big is the gas port on yours yet 308 barrel?

Thanks
 
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Yeah, those are chamber pics...Nope, no agb yet. Have one on hand though. Ive been loading "regular bolt action" loads. Next im going to try the "service rifle" loads and see if that works.
 
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