AR Varmit Rifle Build ?'s

[boatbum101]

Considering building an AR Varmit Rifle
Would like advise & parts recommendations etc . Lets start with upper / lower receivers . Been told that only 3 companies actually make these either Aero ,LMT or CMT regardless of stampings on parts . I believe forged will be good enough & is much cheaper than billet machined . Since extended strings of fire are norm for varmit rig a stainless barrel would be best . I'm seriously considering Shilen with a headspaced bolt . For what I can get this for would only buy a Hart or Kreiger contoured blank . I know there's cheaper options , but some of those are either excellent or not so good ( IE Wilson , Douglas etc ) . I've had both on other service rifles & IMHO the Wilson's are hit & miss , Douglas interiors are kinda rough & foul quickly . Bolt carrier group I believe as long as its Milspec will be suitable . So many on the market , different coatings etc. etc. . I'm also considering either the JP Enterprises single stage trigger or the RRA NM 2 stage . Geissele are fine but costs a lot more . I also like JP's free float tubes & adjustable gas block . Upper either A3 or 4 flat top as rifle will be scoped . Barrel 20 to 24” straight taper bull 1 in 8” twist . Rest of parts again if Milspec should give good service . Sorry , caliber will be 223 Wyled type chambering . Stock / buffer assembly rifle length A2 type . Since I've never built one & haven't touched an AR in 45 yrs I'm in need of advise . So many options available plus I don't know who makes quality parts it's almost sensory overload . Feel free to comment as that's what I'm looking for .

 

[msinc]

I can tell you what I did with mine...I used a White Oak Armament 26" barrel. It's stainless and uses a longer gas tube. I got a side charge Mega billet upper with the Young Manufacturing bolt and carrier to match it. My last one was an American Spirit Arms side charge upper and it was fine but I like the Mega billet side charge with the YM bolt. Ranier Arms has them. I have used the adjustable Jard trigger and it is great once you get it set. The rifle I have now has the two stage Rock River trigger and it is first rate, no complaints. I used the Magpul PRS stock and a Rock River lower. Pretty much everything else is Mil-spec but the actual buffer. I got an Enodine from Brownell's...I cant really tell its there so you might want to save and put the $90.00 or so towards something else.
As far as barrels go...I have a borescope and barrel a lot of actions. I always have a look at every barrel that comes in to the shop. I will say form what I see, Douglas and Shilen are on a par. They shoot fine but you will see tool marks in the barrel. Lilja and Pac-nor are two that I have had good luck with and you will not see tooling marks. Of the cut barrels they are all good and all appear about the same through the scope. All of them require a bit of a break in and they will copper up a little until you get a few rounds down the pipe. I have only had one, an Obermeyer 5R that never did stop copper fouling but if I keep it clean it shoots lights out. Maybe one day it will stop. Best of luck and watch out, there are a lot of gimmicks out there for the Ar platform.

 

[F75gunslinger]

I've got an E.R. Shaw barrel on mine...shoots far better than I ever will. I will also suggest a high rise upper, since you plan on scoping it. It will allow you to use lower risers for the scope. i also suggest a billet upper and lower. They're more expensive, but I believe will last longer over time.

 

[jepp2]

I finished one recently. I went with the Krieger barrel and couldn't be happier. Excellent quality bore and the gas port is in the groove. Very smooth. One reason for picking Krieger was I wanted a 1 in 12 twist. The Speer HP's were coming apart from my 1 in 8 twist. I also had it chambered in 223 since I didn't see the need for 5.56 loads. Just looking for the best accuracy.

I prefer the M16 carrier for the added weight. I went with BCM upper and BCG. I used a Double Star handguard, as I was wanting to same some $. I used a JP modular on an SPR build and while it was nice, it wasn't worth the extra $140 to me.

For trigger I am using my RRA lower with a Timney trigger. I use RRA 2 stage and it isn't nearly as smooth as the Timney.

 

[tomcatt51]

I finished one recently. I went with the Krieger barrel and couldn't be happier. Excellent quality bore and the gas port is in the groove. Very smooth. One reason for picking Krieger was I wanted a 1 in 12 twist. The Speer HP's were coming apart from my 1 in 8 twist.

Bingo, twist is a BIG issue. If you're really building a varmint rifle the faster twists are too fast for the usual 50 and 55 grain varmint bullets.

I used to shoot prairie dogs with an AR-15. I went thru a number of barrels including a 1 in 14 24" bull (.920") Krieger. I ended up with an Olympic Arms 16" 1 in 9 stainless fluted. .920" then .750" after the gas block. It was just more convenient. With the 16" 1 in 9 I could shoot 55 gr bullets. The twist was too fast for 50s even with the lower velocities from the 16". It would shoot 1/2" 5 shot 100 M groups any time you threw the gun down on the bench. 2" 500 M groups. 55 gr Nosler Ballistic tips. Went thru 3 barrels to get one that shot that well and held point of impact as it heated.

The Krieger barrel was the absolute best shooter. 1/4" 100M 10 shot groups with 50 gr Nosler Ballistic tips. It was just long and heavy and really inconvenient.

I found no practical advantage with a longer than 16" barrel on prairie dogs. Out to 600 yds the 55 gr Ballistic tips would turn them inside out with no problem.

 

[boatbum101]

We don't have prairie dogs down here . We do have tons of coyotes & lots of hogs ( which are considered pests here ) . I was originally thinking a faster twist for heavier bullets but I need to do more research . I consider 223 a little light for hogs , but head shots with heavier bullets would work . Most times I use a pistol for the hogs . Krieger , Lilja , Hart & Pacnor are probably the best but are costly & I was trying to keep costs down . Thanks for the info gentleman , you've given me some things to ponder .

 

[MichiganScott]

The advantage of a longer barrel is increased velocity. The advantage of a heavy barrel is that it will absorb more heat during rapid fire and not burn the throat out as fast. For coyote and hogs, there is no need to go longer than 18" in a regular weight barrel.

FWIW, a 55 or 62gr Barnes bullet should give all the penetration needed on hogs, as would a 60gr. Partition.

 

[Doubless]

Don't rule out BHW for barrels. For my money, the rest of the "parts" options with the exception of the fire control group are " a horse apiece" as Midwesterners are known to say...

And it is a shame you are sold on a 223, in my estimation. You don't mention whether or not you are a handloader, but if you are, I would encourage you to look closely at the 6 X 45. BHW did the barrel on mine, and it has been less than MOA with anything I have fed it. Brass is standard .223/5.56 run through the sizer die where it is re-sized and necked up to accept .243" projectiles. Trim length, etc., remain the same as for the .223.

And unless I was just burning to build my own, for what you are trying to do I think I would just see if a Stag Arms 6H is still available. It is a 24" stainless match barrel, but mine is so darned accurate it is boring. Everything I put in the mag goes into one ragged .5" hole at 100...

 

[boatbum101]

Oh yes I reload & have for many years . Shot service rifle in my younger days & still shoot Bullseye . I've also other hunting rifles that could serve the same purpose . The attraction to me is / was the AR platform can be put together cheaper & easier than a bolt gun & if done right sub moa performance is quite possible . 223 is also more economical than the other calibers I've got . Rock River , Fulton Armory & many others build rifles that'd do fine , but why pay $ 1200 to 1400 for one . To me it's more fun with a gun & ammo you built yourself .

 

[MrG5122]

I built one with a Wilson 1:8 22" bull. Spikes bcg. Geissele SDE. It shot very well with the heavier bullets. For whatever reason it loved the cheap American Eagle 50gr polymer tips.

 

[vipermd]

I have an unfired, pre ban, Olympic Arms Ultramatch, SUM,20", I also have a DPMS Lo Pro Classic, 16" Bull, with a Geissle SDE planned. I am looking at 400 yd max for yotes. I was looking at BBTI and 16"-18" was 100 fps, will I get that much more out of the OA @ 400 or will the Lo pro give me enough. I can sell the OA and buy S&W 24 and 624! Suggestions? Be Safe,