Semi auto .308 recommendation

[Trent]

I'd put my FN-AR up against *any* AR10 (even an expensive Les Baer custom), any day of the week, at any range up to and including 800 yards, from either prone or bench, in 5, 10, and 20 shot groups.

I agree it's a fugly rifle. But these babies shoot.

On a related note, surprised no one has brought up Springfield M1A. They have some "tacticool" stuff out there on the aftermarket for them. And I hear they can shoot good, too.

 

[Driftertank]

My PTR-91F, originally purchased for $1175, after a good bit of modification. lol

The HK design is fairly modular, and lots of different variants were produced, many of which have interchangeable parts. As an example, mine has a PSG-1 recoil buffer and a 21E cocking lever. Different FCG's are available, stocks (obviously), handguards (mine's an A3 style, aftermarket), and internal parts.


The groups in the pic were shot at 100yd with Hornady Steel Match 155gr and the smaller group measures 1.75". I'm currently preparing a lot of brass to start experimenting with handloads and hope to get them down cloer to 1". There will be pics...

 

[Snag]

EDIT: He is already considering an AR-10 but is looking for other options.

I'd be torn between an AR-10 and an M1A. If money wasn't a concern I'd look at a SCAR 17s.

 

[theautobahn]

If money wasn't a concern I'd look at a SCAR 17s.

I've personally never shot one, but of all the people I know who have shot SCARs (including the gentleman in question), only one actually liked it (and it wasn't him).

If there wasn't an availability problem, he actually wants an RFB. Which confuses me because they're even less "modular" than the HK's and clones.

 

[helotaxi]

I'd put my FN-AR up against *any* AR10 (even an expensive Les Baer custom), any day of the week, at any range up to and including 800 yards, from either prone or bench, in 5, 10, and 20 shot groups.

Hmmm...Les Baer guarantees a 1/2 MOA rifle. All I've hear about the FN-AR places it in the 1.5 MOA category with the rare example being a 1 MOA rifle.

 

[Ryanxia]

Some good options, I'll let him know if Autobahn hasn't hijacked my thread

 

[DesertFox]

Quote:
Originally Posted by Trent View Post
I'd put my FN-AR up against *any* AR10 (even an expensive Les Baer custom), any day of the week, at any range up to and including 800 yards, from either prone or bench, in 5, 10, and 20 shot groups.
Hmmm...Les Baer guarantees a 1/2 MOA rifle. All I've hear about the FN-AR places it in the 1.5 MOA category with the rare example being a 1 MOA rifle.

I'd have to agree. The FNAR is excellent in the accuracy department and it wins out by a hair over my AR-10. I bought both cause I couldn't decide which. And I already had the M-14 covered...

Too bad there isn't a modular "last shot bolt hold open" HK option. Fatal design flaw to an otherwise fine battle rifle.

FAL is a total winner too - best battle rifle IMOHO, however it won't do accuracy like the FNAR or AR-10.

If camo is your thing, there is the Winchester SXAR, which is an FNAR minus 2 small rails, fluting wearing Mossy Oak Brush pajamas.

 

[TexAg]

I have an SX-AR and it shoots 1MOA, though I have not yet shot Federal Gold Medal Match out of it (I bought a box yesterday finally). It is a super comfortable gun to shoot and I've had no trouble hiking and hunting with it.

 

[Trent]

TheAutoBahn - I have a SCAR17S and love it, so now you know two.

HeloTaxi - I said *MY* FN AR. Because I've seen how my specimen shoots with my handloads. I wouldn't taken an off the rack FN-AR unless I'm given time to work up a load for it.

 

[skywalkrNCSU]

TheAutoBahn - I have a SCAR17S and love it, so now you know two.

HeloTaxi - I said *MY* FN AR. Because I've seen how my specimen shoots with my handloads. I wouldn't taken an off the rack FN-AR unless I'm given time to work up a load for it.

So what kind of groups are you shooting?

 

[theautobahn]

TheAutoBahn - I have a SCAR17S and love it, so now you know two.

Touche' - And I should qualify my statement - it's not that most of these people didn't like them, just that they preferred the ACR and/or regular AR's to the SCAR.

 

[Trent]

Touche' - And I should qualify my statement - it's not that most of these people didn't like them, just that they preferred the ACR and/or regular AR's to the SCAR.

They're CLEAN. I mean, spotless clean. I put 150 rounds of dirty Malasian surplus out of mine earlier this summer, following on the heels of a weekend when I put 150 rounds out of my G3.

The differences in filth were like watching "hoarders" vs. "martha stewart fine living". G3 was crudded to hell and gone (like it always is), while the FN SCAR17S was spotless on the inside. It looked like I had JUST cleaned the thing. I got a TINY amount of carbon on my finger when I ran it across the bolt face. But that was it.

The G3 looked like the inside of a coal furnace.

So what kind of groups are you shooting?

10 shot groups @ 300 yards. 180 grain Sierra Matchkings on Varget. Nosler brass, sorted for weight, neck turned, primer pocket uniformed. Neck sized with air-gauged redding competition collet die, bullets seated with redding competition seating dies. Every charge hand weighed to .1 grain (I don't have a .01 scale yet.. they're damned expensive). Bullets seated .01 off the lands.

I've got the group size down to 1.5", at a velocity 125fps below listed max load in Sierra V edition. Ramp it up any higher the groups open up slightly.

Might be why factory match ammunition wasn't doing so well, *my* rifle likes it just a little mellower.

 

[valnar]

If you want the cleanliness of pistons (vs D.I.) and like the basic AR10/15 type of setup, look into the PWS MK216 as an alternative to the SCAR.

 

[helotaxi]

(I don't have a .01 scale yet.. they're damned expensive).

Yeah, and pretty much pointless unless you just want something to brag about.

 

[Trent]

Yeah, and pretty much pointless unless you just want something to brag about.

Depends on what you're doing with it. I actually had a lengthy conversation with a guy at Krieger barrels about this very topic at one point - I was skeptical, and still am to a large degree. It just doesn't seem to be worth the extra effort.

If I ever had access to one, I'd try identically prepped brass side by side, weighed out to .1 and .01, and fire them through a chrono, just to see if there's any noticeable difference in the measured standard deviation on a 10 shot sample string of each.

If you plot the ballistics out, a 5 fps spread on velocity vs. a 15 or 30 fps spread on velocity range leads to some pretty substantial differences downrange. With every function on a trajectory curve being a nonlinear equation, based on velocity, any velocity differences in initial projectile speed play out profoundly as the round goes down range.

But we're getting in to ballistics and handloading, and way off topic. So I'll shut up.

 

[Ryanxia]

Thanks for all the suggestions, I gave him the list of guns to check into, I believe he's leaning towards a FN-FAL.

Now I'VE got some ideas on a few of those that looked pretty tempting.

 

[Gtimothy]

Another vote for the FAL

 

[helotaxi]

Depends on what you're doing with it. I actually had a lengthy conversation with a guy at Krieger barrels about this very topic at one point - I was skeptical, and still am to a large degree. It just doesn't seem to be worth the extra effort.

If I ever had access to one, I'd try identically prepped brass side by side, weighed out to .1 and .01, and fire them through a chrono, just to see if there's any noticeable difference in the measured standard deviation on a 10 shot sample string of each.

If you plot the ballistics out, a 5 fps spread on velocity vs. a 15 or 30 fps spread on velocity range leads to some pretty substantial differences downrange. With every function on a trajectory curve being a nonlinear equation, based on velocity, any velocity differences in initial projectile speed play out profoundly as the round goes down range.

But we're getting in to ballistics and handloading, and way off topic. So I'll shut up.

If it took measuring powder down to the fraction of a kernel to get low single digit max spreads, then it would be worth it. But even long range competition shooters have realized that a stable load will hold under 10fps max spread with powder weights in the +/- 0.1 or even 0.2gn range. Even if the charges were weighed out exactly, it won't burn exactly the same every time and that difference in burn is what dictates the velocity spread. Slight differences in neck tension, bullet shape, bore fouling, surface areas of the individual kernels of powder and how the kernels are arranged in the case all play a bigger role in the velocity spread than a fraction of a percent of charge weight will.

Some people get extremely anal about such things as powder weight being as exact as possible because they believe it helps. If they believe that it helps it does, but the assistance is purely psychological. I just ran a few numbers from a .308 load I was shooting yesterday (Silver State Armory 168gn OTM using the Sierra Matchking, just shy of 2600fps and extreme spread for the 5 rounds I chrono'd of 8fps with 3 running the exact same 2583fps). At 1000yds, the difference in drift between 10 and 11 mph x-wind made a bigger difference than 25fps variation in velocity. Place emphasis where it is due. Single digit extreme spreads are more than adequate.

To the topic at hand, a semi-auto would not be my choice for long range work. The longer lock time places a greater emphasis on shooter technique and makes it more difficult to shoot consistently. The longer range exaggerates shooter error. This is where the AR-10 has an advantage. It's lock time is already good and by installing a faster trigger like a Geissele Hi-speed you will have the lowest lock time available in a semi-auto. The most accurate rifle is no good if the shooter can't realize that accuracy because his interface with the rifle is lacking.

 

[barnbwt]

I believe he's leaning towards a FN-FAL

He must've realized fun is more important than accuracy

TCB

 

[Trent]

Helotaxi - I agree with what you wrote. By far, the largest contributor to velocity spread that I've found through trial and error is highly accurate neck tension. It easily trumped every other variable I messed with - sorting cases by weight /volume, flash hole uniforming, primer pocket uniforming, and so on. Neck tension (along with proper OAL and relationship of bullet to lands) determines the rate the bullet begins it's trip, in interior ballistics, that's the cat's pajamas.

In a 308 load with 42 gr of Varget, a .1 gr difference is .2380% difference; plus or minus .05 (since .1 scales round off) is only .1190% difference. *IF* this were to translate directly to FPS at the muzzle - which I seriously *doubt* due to the number of variables involved - that's 3 fps (considering a 2600fps exit velocity).

3fps would equate to 1.5fps spread (maximum), and probably much less than that on a standard deviation with a good barrel with single point cut rifling.

Such is how the conversation I had with the "expert" at Krieger went.. but he was still dead set on justifying his use of a .01 scale.

Now, even 1fps will introduce a small, but measurable effect that is amplified as range progresses - but that margin of error introduced is negligible compared to the shooter and his ability to read the environment and hold the sights steady.

 

[helotaxi]

And that 1fps is impossible to do away with anyway .

I'm guessing the Kreiger guy was a benchrest shooter. They're the only group I've met that is that adamant that the silly lengths that they go to not only matter but are ESSENTIAL!

 

[Trent]

helotaxi - yes, that group is more religiously zealous over their processes and particulars than entire boards full of Glock, FiveSeven, 1911, and AR-15 enthusiasts combined would be.