Jump to content
308AR.com Community
  • Visit Aero Precision
  • Visit Brownells
  • Visit EuroOptic
  • Visit Site
  • Visit Beachin Tactical
  • Visit Rainier Arms
  • Visit Ballistic Advantage
  • Visit Palmetto State Armory
  • Visit Cabelas
  • Visit Sportsmans Guide

Yet Another Build Thread - My First Large Frame AR


supertux1

Recommended Posts

 

I am building my first large frame AR for shits and giggles and money is no object.  

Philosophy of Use / Design Considerations:

  1. Long-range precision semi-automatic paper puncher, range toy.
    1. Let's be honest, %99 of the time the rifle is going to be used at one of the ranges near me or on private land ringing steel. 100 yards - 1000 yards.
    2. I think it would be a fun hobby for me to hone my marksmanship skills with a rifle that will always shoot better than me, going for tight groups, tack driving etc...
    3. Bullet design and ballistics fascinate me, I want to develop the most consistent custom hand loads and what not.  
  2. Hunting Deer
    1. I have friends with land who like to hunt, and I've been invited a few times, but I'm not doing that with an AR-15.
  3. SHTF Sniper Rifle 
    1. I like the idea of being able to engage multiple targets quickly at various distances beyond the effective range of an AR-15.
    2. I like the idea of being able to swap the upper between 6.5 Creedmoor and .308 if ammo resupply every becomes a problem.
    3. I don't want to carry two rifles, one for hunting and one for self-defense.  

Lower:

AP M5. The lower is going to be set up as a rifle build with features that enhance the fit to my body and accuracy, such as the MagPul PRS, two-stage trigger and a grip with a palm rest. 

I have long arms and long bony hands with a long neck and long face, so adjustability is important. I shoot with a squeeze bag under the stock or the palm.

Nothing fancy with the LPK. The buffer system is going to be a JP Silent Captured Spring with heavy tungsten weights because I eventually want to run a can. 

Plus I don't like the 'sproing!' sound of traditional springs and buffers. ?

(After my usual NICS delay, this is mostly completed as pictured, waiting for a few more parts.)

Upper:

AP M5. I am leaning towards 6.5 Creedmoor. I love the external ballistics properties of these bullets, even if it doesn't have the same terminal punch as .308. 

Remember, my first PoU is range use. I may buy a basic .308 upper for hunting/SHTF, but that's a secondary consideration.

For the 6.5 barrel, I am looking at two options and will decide on one shortly:

  1. The first is a Proof Research carbon fiber wrapped barrel 22"
  2.  JP 22" barrel with the heat sinks.

Both are rifle + 2" length gas systems which should minimize premature BCG unlocking/movement when suppressed. Both will be fitted with a JP adjustable gas block and JP's Rapid Configuration tubular handguard. I might put 45 degree offset BUIS on the rail and maybe a low hand grip and that's it. 

BCG is a JP VMOS system with the heavy tungsten weights and JP High Pressure Enhanced Bolt head spaced to the barrel. (I'm not doing the tungsten firing pin.)

Muzzle treatment will probably just be a flash hider or minimal brake/comp until the can gets out of ATF jail.

I'm not going with a full brake because I like the guys who sit next to me on my range and they like me and I want to keep it that way.

(With 6.5 and the JP heavy parts, recoil isn't going to be an issue anyway.)

For a bipod, I will probably use some $20 detachable bargain special. IMHO bipods keep the rifle from falling over when you're cleaning it / not shooting from it. (I use a bag.)

Optics:

I am most experienced with mildot reticles, ranging with mildot, and mildot turrets, so I am thinking of either the Burris or Bushnell scopes with the Horus reticles. 

Something in the range of 4-20x50, FFP. I like the idea of zeroing for 100 yards and then never touching the turrets ever again. 

Optic rings from either the scope manufacturer, JP or Geissele.

Well that's it for now. I'll update as the build goes. Here's a picture of progress so far and some tools.

IMG_1443.JPG

Link to comment
Share on other sites

  • Replies 87
  • Created
  • Last Reply

Top Posters In This Topic

6 minutes ago, 98Z5V said:

You certainly didn't piss around with the trigger, stock or the charging handle - excellent parts.  Have you set the trigger up yet?

I watched Bill's videos and read the instructions and set it up the way he says, but I haven't measured the pull on it.

I can tell you that the first stage is very light and smooth and the second stage breaks with hardly any force at all.

Seems like just a few ounces and breaks like a glass rod.

I am reluctant to pull it too much because of smashing into the lower / my thumb, it's got some force! 

Link to comment
Share on other sites

If money is no object, don't cheap out on the bipod. Magpul has a nice one coming out this summer for $110. Also, the palm shelf will likely do nothing except get in the way of any position other than prone, I learned this the hard way. This is only my humble opinion though, take it for what it's worth.

Link to comment
Share on other sites

3 minutes ago, Matt.Cross said:

If money is no object, don't cheap out on the bipod. Magpul has a nice one coming out this summer for $110. Also, the palm shelf will likely do nothing except get in the way of any position other than prone, I learned this the hard way. This is only my humble opinion though, take it for what it's worth.

Good to know! I was thinking of maybe the Atlas but I will wait for the MagPul one if it's half the price. Money isn't a problem but only if it's paying for quality. ? (So the charging handle -- yeah I know haha, I got it and the trigger when Brownell's had %25 of Geissele parts plus another %10 off overall code -- I couldn't resist! )

At the range, I shoot from tables, some wooden, some concrete and don't like how the bipod jumps around, it's kind of hard to load the bipod when there isn't anything on the bench for it too. I get better groups from my Weibad sandbag or range pack when I have to shoot from a hard surface. At long range we shoot prone on the dirt and the bipods work well when dug in there. 

Link to comment
Share on other sites

Just now, 98Z5V said:

What kind of distances have you shot at previously?

300 yards with 5.56 

800 yards with .308 

We don't have very many public 'long ranges' here beyond 300 yards (like 2 maybe) but I may be getting a private membership to one that is 1200 yards.  (On the waiting list.)

 

 

Link to comment
Share on other sites

Yeah, there's not much in WI, at all. Lodi is the only thing I could find. 

300 yards with a 5.56 is iron sights, man.  That's not even a challenge.  800 yards with a .308 is different. What kind of a .308 was it, and where the hell did you find the space to shoot it in WI?

Link to comment
Share on other sites

1 hour ago, 98Z5V said:

Yeah, there's not much in WI, at all. Lodi is the only thing I could find. 

300 yards with a 5.56 is iron sights, man.  That's not even a challenge.  800 yards with a .308 is different. What kind of a .308 was it, and where the hell did you find the space to shoot it in WI?

Yes, iron sights. I don't really count 5.56 a real long-range precision projectile but some guys have a lot of fun accuratizing their AR-15's and what not. It is certainly a good caliber for the ranges around here. I'd rather spend the money building a large frame rifle that can shoot more ballistically efficient rounds and is more appropriate for hunting which I'm just getting into. 

There is a 600yd range in Columbus, but that's a club and I've only ever shot there as a guest. They're really strict about the use of their long range (nothing less than .308 and training is required) and it isn't always open. They want RSO supervised long-range shooting, which is understandable.

The one in Lodi is Winnequah Gun Club and they are the private fancy one with the 1200 yard range. I'm hoping to get in there with a referral from a service member. I was doing ballistic calculations with 6.5 CM ELD bullets and 1400 yards came up as the max supersonic range so that would be perfect. (Members also get a discount on Vortex optics which I'm told is more than the price of the membership. So we'll see. There's a waiting list.)

A little further away is McMillan Sports Center which offers a 300 yard public range, but they want $30 a day or $400 a year membership to shoot there. A little steep and far away but currently the best medium-ish range option for most folks unaffiliated with a club. I've shot my AR there and I'm getting bored. 

Not too far away, the DNR is building a brand new fancy 100, 50 and 25 yard public range which is supposed to open this summer after they fix the damage recent rains did to the berms. That'll be great for scope sight-in and zeroing and coppering up a brand new barrel, tuning the gas system, 100 yard trick shots, one ragged hole etc... There is also the Dane County Law Enforcement Training range which is 100 yards and open to the public on weekends for $10. 

The 800 yard shooting I've done is on an acquaintance's farm up north, private land, no benches, just dirt. Usually, we lay on the ground or in the bed of a truck and shoot at random junk, steel etc... I do that a few times a year and get use a borrowed Remmington 700. I've been hunting with that too, so now I'm basically hooked on the bigger calibers. ?

 

 

Link to comment
Share on other sites

35 minutes ago, supertux1 said:

A little further away is McMillan Sports Center which offers a 300 yard public range, but they want $30 a day or $400 a year membership to shoot there.

I shoot there 3-4 times a year

Link to comment
Share on other sites

 

23 hours ago, supertux1 said:

 

I am building my first large frame AR for shits and giggles and money is no object.  

Philosophy of Use / Design Considerations:

  1. Long-range precision semi-automatic paper puncher, range toy.
    1. This would most likely be a heavy-bull contour, and minimally 22". Not your lightest option.
    2. The best precision would be a pulled 416-R stainless barrel. Also not know for it's longevity of life.
  2. Hunting Deer
    1. Unless you're a tree/stand "hunter", you are going to hate any >10 pound rifle.
    2. Most hunting barrels are light contour and <20", which is the polar opposite of the previous barrel.
  3. SHTF Sniper Rifle 
    1. This option is completely opposite of both previous options.
    2. Neither of the previous options would be advised for sustained strings of fire. You will either burn out the soft rifling of the 416R barrel, or you will heat the lightweight barrel beyond it's ability to maintain accuracy.
    3. A combat barrel is generally made from 4140 or 4150 CMV and then chrome lined or nitride treated. It requires a girth that is acceptable for portability, but still sturdy enough to maintain accuracy.

You gotta pick ONE brother. You can't have it all in one upper.

Honestly... The Faxon 16" or 18" Gunner barrels are more barrel than what 99.9% of the shooters will ever surpass in ability. I personally wasted $$$ on a PROOF CF wrapped barrel, and if I could go back I's slap myself I would.

Build the 22" heavy 6.5cr... Then build the lighter 16" .308win. While they each have a task, I'll bet dollars to dimes you shoot the 16 incher 100x more than the big fat paper killer.

Link to comment
Share on other sites

31 minutes ago, Robocop1051 said:

 

You gotta pick ONE brother. You can't have it all in one upper.

Honestly... The Faxon 16" or 18" Gunner barrels are more barrel than what 99.9% of the shooters will ever surpass in ability. I personally wasted $$$ on a PROOF CF wrapped barrel, and if I could go back I's slap myself I would.

Build the 22" heavy 6.5cr... Then build the lighter 16" .308win. While they each have a task, I'll bet dollars to dimes you shoot the 16 incher 100x more than the big fat paper killer.

3

Yeah - I hear you, the order there is listed as more of like a priority list, not a list of must-haves -- such a rifle doesn't exist, so there is always a compromise somewhere.

That being said, if there's a part that works with all three uses, or does one well and another case acceptable, then it gets consideration over a part that works with only one or two, even if it is a bit expensive. Buy once, cry once. 

The Proof CF barrel has my attention because it purports to have all the same internal ballistics (or better) than a traditional heavy steel barrel while only having %60 of the weight or something like that. That fits the bill for 'precision' on the range, but also maybe not a pain in the ass to lug around for 'animate' targets... What didn't you like about it, besides the price?

I am definitely going to take your advice and build a shorter barreled .308 upper after this build is done.

(It may work out that I have an extra upper anyway, due to my first one being stolen from the mail. Grr...)

 

Link to comment
Share on other sites

31 minutes ago, supertux1 said:

 

(It may work out that I have an extra upper anyway, due to my first one being stolen from the mail. Grr...)

Probably one of those dirty granola eaters from up there in Madison.......

Link to comment
Share on other sites

This group has a sense of humor by the way. What you want is the "Unicorn" of AR's. A rifle is like a boat, a series of compromises to make it do a number of things. A short light hunting rifle and a thousand yard paper puncher are at different ends of the spectrum. And I won't even bother with the SHTF scenario. Think two rifles each that can do one well or one that MAY be adequate at both.

Link to comment
Share on other sites

Yeah you guys are hilarious!

Arrived today:

JP HP Enhanced Bolt 

JP Heavy VMOS 

JP Heavy Silent Capture Spring

Extra steel weights and springs to tune.

After talking with the fine folks at Proof they recommend the Superlative Arms adjustable gas block and the head spacing with that bolt won’t be an issue. 

PMag, Upper and LPK will be here tomorrow. 

I’m starting to think this is going to turn out like a JP-LRP07, but with a better trigger and barrel. 

 

Link to comment
Share on other sites

23 minutes ago, supertux1 said:

After talking with the fine folks at Proof they recommend the Superlative Arms adjustable gas block

Any reason given as to why? I found the bleed of function on this block to be inadequate for the 308, never could adjust far enough to not have lock back as the manufacturer instructs making it a standard restrictive style block with a super long adjustment screw.

Link to comment
Share on other sites

50 minutes ago, washguy said:

Hmmmmm.... complicated $hit play.....What say you 98Z?   :laffs:   Wash

I think it goes somthing like don’t complicate shit with complicated shit

 

They didn’t sell you the under coating too did they???

Link to comment
Share on other sites

5 hours ago, jtallen83 said:

Any reason given as to why? I found the bleed of function on this block to be inadequate for the 308, never could adjust far enough to not have lock back as the manufacturer instructs making it a standard restrictive style block with a super long adjustment screw.

I asked them a lot of details about suppressed applications with their camgas length, what is known to work with their barrel. Proof said that a lot of their guys used that specific one on their personal setups. Got back to me quickly and answered a lot of my questions.

Good to know that it might not work for all 308 applications, but hopefully I can address any cycling issues with the wide variety of springs and weights. 

 

 

 

 

 

 

Link to comment
Share on other sites

5 hours ago, supertux1 said:

Good to know that it might not work for all 308 applications, but hopefully I can address any cycling issues with the wide variety of springs and weights. 

Works fine using the restrictive side of the block, just not the by-pass mode which is what the big selling point is. On restrictive mode it is really no different than others on the market.

Also when on bypass with a suppressor it blasts the can with a jet of hot gas, no big deal unless you worry about can finish or you run a cover on the can.

Edited by jtallen83
Link to comment
Share on other sites

The whole idea of venting gas from yet another location on the AR makes no sense to me. Ideally, you'd have as much gas as possible going towards the muzzle, with just enough going to the BCG to cycle. What's with just dumping hot gas forward of the optics/sight system when there's no need?

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...