Precision Carbies?

[Pat Tarrant]

My limited experience is with personally owned guns an funds are limited, so for now, I'm sticking with 5.56. I built a Mk12 inspire gun (Centurion Mk12 barrel, carbon fiber handguard, Surefire brake, etc.). However, I found the weight to really be unacceptable for a 5.56 gun that I do. Intend to just shoot from the bench. I've been thinking about going to a shorter, lighter barrel, around 16" ((thinking BCM stainless 16" barrel or similar setups) and scaling back on optics from my current 3-12 to a 1-6.

I know the 16" with low power variable or optics are gaining a lot of traction, especially in the competition circles, but what does everyone think of these setups for defense (or duty) use? Seems that they have enough optics to make good shots out past 400 yards and velocities shouldn't be this far off from 18" barrels.

Thoughts? Experiences?

 

[tylerw02]

Actually compared a pair of BCM SS 410s on velocity over the weekend. 16" was 40 FPS slower than 18" with 75s throw the same suppressor on both and they were even on velocity at 2690 FPS. I must say that my chrono typically runs 30ish FPS slower than Ballistic's numbers based on truing.

I cannot comment on them about duty use. For shooting courses/training, I find I prefer 16" to 18". I've found 16" middy rifles run better for me than 18" middy or rifle. The 16" seems to handle better and there is no accuracy or velocity penalty in my experience. I'm sure that could change with different loads, however.
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[tylerw02]

The KMR helps cut down weight. I prefer a 2.5-10x optic. I'm anxious to try a 1-6x or 1-8x but I would put that on a 14.5" carbine rather than a precision. I like the magnification for my eyes.
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[regdudedrtyjob]

I like my set-up, but if I had a mulligan, it would be different. I'm debating whether or not a BCM BFH barrel would have been a better choice than the Standard Barrel for accuracy. I would have a hard time not going the KMR route, but I still like the Centurion C4 I have now. For glass, I would save up and go with the Nightforce 2.5x10 like I originally wanted. Lastly, my ALG QMS trigger is good, but to squeeze some more accuracy I would go with the ACT or an SSA/SSA-E.

Getting back to your question of this set-up for duty/defensive use? Duty, absolutely, but not as the one and only optic/RDS allowed. Too much of a force multiplier, better target acquisition at range, intel gathering (barricaded standoff), and target identification. Defensive purposes I see as inside the home/bedroom/trailer home/whatever, so personally I would want something simple, bright, and dependable. Basically a T-1.

 

[son of liberty]

My pet load I loose 50fps going from 20 inch to 16 inch. With suppressor on my 20 its 26 inches , with it on my 16 its 22 inches, that dont seem like a whole lot but with the rifle slung up across my chest it puts the muzzle above or below my knee depending. I am running a high power scope on both with RTS and or RDS as back up, sure the strait up RDS carbine is a bit faster according to my times, but the broad range of scoped carbine seems to be working well for me.

 

[Pat Tarrant]

Great info. I have a 14.5" mostly BCM gun with a T1 thAt is my primary cqb gun, but I'd like something that could still run up close and be handy, and it looks like 16" guns give up little to no velocity, but are lighter and more handy.

Due to budgets, I'm really looking at the Vortex 2.5-10 ffp scope that I can get for a third of a Nightforce. My other options are Leupolds VX-6 1-6 with their CMR-2 reticle (more close range oriented) and my current Bushnell Elite Tactical 3-10 with a non-illuminated G2 reticle. It's the heaviest, but has decent glass, the most magnification, and I already have it. Each has advantages, though, and the Vortex I think is my front runner unless I can really find a NF for cheap.

 

[tylerw02]

I'm running the Vortex on a 16". I'm 20 FPS slower than an 18" with the same 75 gr load.


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[FailureDrill]

Intend to just shoot from the bench.

I'm curious why rifle weight would be an issue if this is your goal?

Seems like your current setup and optic would be perfect for that.

 

[Pat Tarrant]

You're right, it would be. However, I failed in being clear in my original post. I HAD been intending on shooting from fixed positions, but the more I thought of it, the more I wanted something shorter and lighter (no more than 11 pounds fully loaded). With a shorter lighter gun I could use it to backup my other carbine plus have it light enough to take into the field, which isn't part of my job, but I'd like to be able to keep it maneuverable with solid engagement ranges to about 500 to 600 yards.

 

[Pat Tarrant]

So, after a bit of research and considerations, I'm thinking of the following:
16" BCM SS barrel (I kin of wAnt the ionbond variant)
15" KMR handguard
Vltor upper with current LWRCI bcg
Not sure if I want to keep my PRS stock or go with a carbine stock
Lower carried over is a Noveske with a Geissele flat trigger
2.5-10x32 Vortex (lower cost holdover scope until I can get something like NF)
Larue or Bobro cantilever mount

There are a couple barrels I'm considering with the BCM holding the lead for its acceptable accuracy and ability to stand up to hard use. Other options include:
Rainier Ultra Match
Ballistic Advantage Hanson barrel
Northtec defense is supposed to have very good barrels at reasonable prices but I'd be a test case.
I'm a little hesitant to go with a Wylde chamber, as this would have a steady diet of 5.56 rounds but if the consensus is that it's safe and more accurate, I'll be more comfortable with them.

 

[son of liberty]

My last 2 builds used ODIN works barrels, Stainless Mcgowan blanks, hand lapped, 1 MOA guarantied, Wylde chambered. They dont offer a bunch of profiles , but I have seen no to negligible POI shift due to heat in there rather typical profile.

 

[Andy Beefcastle]

Okay, here's the thing- are you using the rifle professionally?
Are you doing regular multi-day training with the rifle?
If the answer to both of those is "no", then consider the reality of what you are looking for. If this is for a SHTF rifle, be realistic about when the weight will really be a hinderance.

If you really want a light precision setup, get a Proof Research carbon fiber barrel, and then put on a BCM KMR magnesium handguard. That will pretty much make your rifle as light as it possibly could be.

I built a 16" carbine using a WOA stainless steel barrel for my brother for a compact coyote rifle for when he goes tromping around in the woods while scouting prior to deer season. The rifle is sub-moa accurate. The rifle would have no problem being a defense rifle, as I built it using quality parts.

That said, 400yds for a non-military/LE personal defense rifle is pushing the limits of probability. However, working in the hypethetical, If I needed a 400yd rifle, I would much rather be working with a 6.8SPC or something heavier, like .308.

 

[Pat Tarrant]

Thanks, Andy. For me, personally, I will not be using this rifle professionally in any conceivable course of events. It will be for personal use, possible home defense (backup to my primary 14.5" home defense rifle), possible class work (again, backing up my primary) and seeing if I have any aptitude for longer range shooting, out to 500-ish yards. Part of my original intent of the thread was my personal use. Part of it was for others who may have use for a lighter weight 5.56 gun professionally, that is also able to reach out to longer distances.

Personally, I've sold off almost all of my previous 18" gun (I kept the Noveske Gen 2 lower, DD parts kit and Geiselle trigger), and bought a 16" BCM 410 Stainless KMR15 upper, and am waiting on a 2.5-10x32 Vortex PST. The gun is much lighter than my 18" gun was, and without the optic or bipod, it's maybe a touch lighter than my 14.5" BCM BFH with an Apex handguard. As I'm still waiting on the optic, I haven't had the oportunity to see what this gun can do, but others have had success with it, and I know the 410 SS should last a little longer than the 416 SS that i previously had. Keeping it at 16" and light lets me use it in more roles than the big heavy 18" could have been, in my case.

 

[ptrlcop]

Distance/= precision.

There are plenty of scenarios where someone would want to be able to be able to shoot with precision that don't involve distance.