New build; starting with the upper.

[Former11B]

I haven't gotten all the pieces yet, but I got enough to start!

I have been a Rainier fan for a long time, so I started with:

Upper: Rainier Forged Mil-Spec
BCG: Rainier Precision Match Grade Nitrided BCG
Charging Handle: Avalanche Mod 2 CH (not pictured; it was a pre-order that will ship soon).
Rail: Fortis 14" REV 2.0 M-Lok
Barrel: Keeping it under wraps for a reason, but it's definitely Rainier . Will be using a Griffin Armament muzzle device for a Recce 5.
Gas Tube: Lantac Black Nitrided; Intermediate length
Bipod: Harris w/ Odin M-Lok mount
Scope: Sightron S-Tac 4-20x50mm w/ MOA-2 reticle. Found a deal with it almost 50% off and it has better glass than a friend's Sightron SIII, and it seems more crisp than my Vortex HST 4-16x44

I'm going to be using a lower I already have temporarily; it'll have all the usual suspects...Magpul, SOPMOD, Geissele, etc. I'll likely end up getting a Rainier lower unless another nice one happens to come my way in the meantime.

My goal is to build a very precise, very accurate AR, lighter than your typical SPR, more reach than your typical Recce, but could easily do the job of both.

[alamo5000]

Barrel: Keeping it under wraps for a reason, but it's definitely Rainier . Will be using a Griffin Armament muzzle device for a Recce 5.

Secrets amongst friends???!!! *GASP!*

So what grain weight of bullet are you aiming to use for this?

[Former11B]

Secrets amongst friends???!!! *GASP!*

So what grain weight of bullet are you aiming to use for this?

When I know more, I'll post more

But I'm looking at running 69s or 77s; I have Tipped Match Kings to load in both weights.

[alamo5000]

When I know more, I'll post more

But I'm looking at running 69s or 77s; I have Tipped Match Kings to load in both weights.

So we are looking at a 1:8 or 1:7...

My goal is to build a very precise, very accurate AR, lighter than your typical SPR, more reach than your typical Recce, but could easily do the job of both.

I am using a Rainier barrel on my regular rifle and it checks all those boxes except maybe the "lighter than your typical SPR" (I have no clue how much an SPR weighs).

My barrel is a Rainier Select. UW recommended it when I was doing my first ever build and there is nothing at all to complain about there.

I can tap the targets out to 800 yards with 69 grain SMK. On my long range that I use the 700 yard plate is actually more difficult. An 18" square at 700 yards in the wind is a real bitch sometimes. Plus the placement of that plate is right where it opens up to cross winds but I can do it regularly in the right conditions. On some days that plate is difficult to hit.

On the short end at 100 yards the best group I ever did was about 1/2 MOA at 100 yards for all 10 shots. I don't know the official way to measure groups though. (do you measure from the outside edge of the hole or the center line?) Either way I could cover up all 10 holes with a dime. (.7 inches)

I honestly haven't shot a group (at all) since then...I just wanted to see what it could do at the time. Now I'm not even bothering to weigh my cases or getting super precise powder charges. Accuracy suffers but it's good enough.

Anyway it's definitely possible to do what you're after performance wise. I couldn't be more pleased with mine. I am still trying to figure out the most efficient and effective way to throw the most precise charge in history every time

[Jerry R]

I don't know the official way to measure groups though. (do you measure from the outside edge of the hole or the center line?)

I measure from the outside edge of the two widest shots, and then subtract one (actual) bullet diameter of the round being shot. That gives the center-to-center group size. C-t-C is what most post - it's smaller

[SINNER]

Maybe that's why I can't get those 1/4 MOA groups. I've always measured the largest point of the group. Outside edges of the two holes furthest out.

[Former11B]

So we are looking at a 1:8 or 1:7...

1:7.7

I am using a Rainier barrel on my regular rifle and it checks all those boxes except maybe the "lighter than your typical SPR" (I have no clue how much an SPR weighs).

My barrel is a Rainier Select. UW recommended it when I was doing my first ever build and there is nothing at all to complain about there.

I can tap the targets out to 800 yards with 69 grain SMK. On my long range that I use the 700 yard plate is actually more difficult. An 18" square at 700 yards in the wind is a real bitch sometimes. Plus the placement of that plate is right where it opens up to cross winds but I can do it regularly in the right conditions. On some days that plate is difficult to hit.

On the short end at 100 yards the best group I ever did was about 1/2 MOA at 100 yards for all 10 shots. I don't know the official way to measure groups though. (do you measure from the outside edge of the hole or the center line?) Either way I could cover up all 10 holes with a dime. (.7 inches)

I honestly haven't shot a group (at all) since then...I just wanted to see what it could do at the time. Now I'm not even bothering to weigh my cases or getting super precise powder charges. Accuracy suffers but it's good enough.

Anyway it's definitely possible to do what you're after performance wise. I couldn't be more pleased with mine. I am still trying to figure out the most efficient and effective way to throw the most precise charge in history every time

I have pretty much some of everything from Rainier, barrel wise. I have a Select barrel (before they were all MEDCON), Match/SPR, and Ultramatch (mod 1).

I've spent time working loads and chasing groups, and shooting targets at distances....I have a couple go-to loads in 69gr and 77gr that work well.

[UWone77]

Now that's it's going out to you, feel free to post what you're using.

[BoilerUp]

Maybe that's why I can't get those 1/4 MOA groups. I've always measured the largest point of the group. Outside edges of the two holes furthest out.

Yeah, that math makes 1/4MOA out of a .308 literally impossible.

[Former11B]

Letting the cat out of the bag.





I'm going to be testing a Rainier Arms Ultramatch Mod 2 16" .223 Wylde, intermediate gas barrel

https://www.rainierarms.com/barrels/...-page-product1

I chose the fluted model because it's 3oz lighter than the non-fluted version and 10oz lighter than the 18" Ultramatch Mod 2. I thought it was significant enough reduction in weight of a difference with only a slight decrease in velocity due to length that it was worth the shot

I'm looking at getting a Rainier forged lower to complete this; I like the ambi billet lowers but I want the simplicity of the forged lower. I'll get another B5 Bravo/SOPMOD and something from Geissele or CMC to top it off.


I'll be loading up some ammo soon to test

[Jerry R]

Nice ! Following this with great interest.

[Pyzik]

Great looking build so far!

Funny you mention that barrel.... I may or may not be swapping out my BA SPR barrel with an 18" fluted RA mod 2.

[Former11B]

Great looking build so far!

Funny you mention that barrel.... I may or may not be swapping out my BA SPR barrel with an 18" fluted RA mod 2.

I'll have my 16" by Friday. I hope to be shooting it Saturday!

I've been prepping brass like crazy; I should have a bunch of test ammo loaded in the next couple nights so I can build the rifle Friday and shoot this weekend

Any reason for the 18" ? The fluting helps; the 18" barrel is 6oz lighter than the non fluted version.

[UWone77]

I'll have my 16" by Friday. I hope to be shooting it Saturday!

I've been prepping brass like crazy; I should have a bunch of test ammo loaded in the next couple nights so I can build the rifle Friday and shoot this weekend

Any reason for the 18" ?

Dude this what I like to hear! Can't wait to see the results man.

Next time we need to get you a .308 barrel

[Pyzik]

I'll have my 16" by Friday. I hope to be shooting it Saturday!

I've been prepping brass like crazy; I should have a bunch of test ammo loaded in the next couple nights so I can build the rifle Friday and shoot this weekend

Any reason for the 18" ? The fluting helps; the 18" barrel is 6oz lighter than the non fluted version.

Just for the little extra oomph and to have something different than 16".

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