Building a Precision Rig

[toolboxluis00200]

Most of my carbines are general use oriented. 14.5 - 16" guns that are used for training, plinking, loaning, ect. I've never really built a 5.56 gun with strictly precision in mind. In fact when I think about it, my .308 builds are not really precision oriented either.

Anyhow, when I received my Rainier Arms Mod2 Billet Set, I set out to start building an accurate 18" blaster. So far here's the upper:

Rainier Arms Mod2 Billet Upper
Rainier Arms Ultramatch 18" SPR Barrel (Rifle Gas)
Rainier Arms Match NiB BCG
Rainier Arms Gen2 FORCE Rail 15"
Rainier Arms Raptor
Geissele Super Gas Block Pinned







Played around with the muzzle devices between the RAC and Epsilon. I think I want to go with a brake on a 18" possibly a suppressor mount. We'll see.

More to come as this progresses.

holy cow that looks killer

[Slippers]

Rainier certainly has some really nice looking billet receivers these days. The new force rail is also pretty spiffy. It has to be super light with the huge cutouts.

[mustangfreek]

Wheres the pics of the lower......

What stock your planning on using?

[UWone77]

Wheres the pics of the lower......

What stock your planning on using?

We're slowly packing for a December move, so I'll get a picture in when I can of the lower.

I'm going to use a Magpul PRS for the stock.

[SINNER]

Although I am speaking about the .308 version those Rainier Ultra-match barrels are some of the nicest made barrels I have seen. The chamber is a work of art.

I really need to up my photography game to post any pics around here. LOL

That upper is a work of art.

[Stickman]

Looks Good!

[UWone77]

I can't decide whether to go with an entirely new optic, or just cannibalize an existing upper for the optic. Can never have enough optics, but then again, $$$

[Ride4frnt]

I can't decide whether to go with an entirely new optic, or just cannibalize an existing upper for the optic. Can never have enough optics, but then again, $$$

Those pesky $$$ will get ya.

[Ordnance]

Something I could shoot a mile with reliably.

There is no such thing as reliable at a mile. And most supersonic rounds do not go transonic shortly after 500yds, for instance most 308's you're looking at 1k+yds depending on your barrel length and load. Hell, I've taken my SPR with an 18" BBL and factory 77SMKS out to 900+ even though they were going transonic at around 800+ but it doesn't matter because the round remained stable and bucked the wind better.

Even so if that is your goal then you'll want to look at a magnum cartridge and a bolt since it can handle higher pressures. Your best best would also be a magnum cartridge with a nice gain twist barrel and a heavier pill in something like a 7mm Rem Mag, 6.5CM SAUM, 300WM, or 338 Lapua/Norma/Edge since they're designed for better performance beyond 1K+. The 6.5 Grendel is a great round, but beyond 1K+ its performance will not stand up to the wind as reliably as a heavy.

[Ordnance]

We're slowly packing for a December move, so I'll get a picture in when I can of the lower.

I'm going to use a Magpul PRS for the stock.

You don't necessarily need the PRS if you're building out a small frame. I have a UBR on my SPR with a ADM mount and I get a perfect cheek weld. On larger frame AR's because of their design it often requires a higher comb, but on he small frame it isn't necessary most of the time.

[UWone77]

You don't necessarily need the PRS if you're building out a small frame. I have a UBR on my SPR with a ADM mount and I get a perfect cheek weld. On larger frame AR's because of their design it often requires a higher comb, but on he small frame it isn't necessary most of the time.

Oh but it is necessary.

I have an extra PRS collecting dust. vs I'd have to go buy a UBR.

[Ride4frnt]

Oh but it is necessary.

I have an extra PRS collecting dust. vs I'd have to go buy a UBR.

Ha! That's why my 18" has a A2 stock and not a PRS. I will say the A2 stock grew on me a lot more than I thought it would. Still needs replaced.

[Ordnance]

Oh but it is necessary.

I have an extra PRS collecting dust. vs I'd have to go buy a UBR.

LMAO... Good point!

[UWone77]

Thought I'd update some of my build threads.

Haven't put my PRS on, and waiting on my trigger, and a BAD 45 degree selector to come back into stock. Most of my projects will be taking a backburner for the rest of the year as I'm packing up to move.

[DutyUse]

Have you used the Rainer extended mag much? Thoughts?