I'm not the guru, but can tell ar15 and ar10 different lower receiver. And they maybe mil spec materials, but not a complete unit in . I E each manufacturer kinda does their own thing

 

for an ar10 the receivers are not all the same. There are at least 2 I know of ,and maybe more. Think the most common is dpms gen 1. if you buy a complete gun all should work fine, if you buy parts or sub assy be very careful.

 

Yes 2 flavors of receivers: Armalite pattern and DPMS pattern. A 16 inch barrel is good for 200-300 yrds tops. If you want to reach out to 600-1000 you are into a 20-24 inch barrel with a free floated barrel and a 1-10 inch twist rate. I'm sure accessories are available for either pattern but it is personal preference. Also, I would go with the pattern that has cheaper magazines. Chamber in 308 Win and you can still shoot 7.62 X 51

 

Don't have time or expertise of every question. However, I will give my opinion, since I also am searching for what you are after. Yes, ar-10 and ar-15 lowers are completely different.

I too dispise these short barrel lengths on AR's. What I'm going to do is order a complete ar-10 lower from Aero with Mag Pul gen 3 prs stock. Next, I'm going to replace the trigger with a drop in Trigger Tech 3.5 pound trigger. While this arrives, I'm going to order an upper in 308 with 26 inch barrel from D-Tech in northern MN. This guy uses Shilen blanks and will make any upper you want.

Just letting you know there's better options out there than the limited factory offerings.

 

Is a bolt with dual extractors a good idea, or a fix in search of a problem on .308 AR-10s?

Edited ejectors to extractors, my goof.

 

Is a bolt with dual ejectors a good idea, or a fix in search of a problem on .308 AR-10s?

Stick with proven Mil Spec parts----simple yet works and easy to replace and find. Most issues we found using the AR in high power matches was that a weak extractor spring was the cause of extraction issues. Use a heavy duty extractor spring and support spring buffer\o-ring and it will work fine. Keep extra new extractor springs handy as these are throw away when they get weak.

 

Don’t know about an AR, but bolt gun, .308, 16” brl with good optic, and good bullet. You can ring steel at 500 yards all day long. I know a guy with a. Remington 700, 16” brl, shoots 155g Amax out to 700 yards consistently.

 

My son should be on this forum for this post thread. He builds AR's from the ground up and does a great job!
Properly loaded, and in a well tuned firearm, a .308 can reach a long long way. Military snipers are proof of that for decades.
I agree that the longer barrel is better. 20" minimum. I hate the short barrels....
LR10 is the DPMS style lower - AR10 Armalite - cannot mix uppers / lowers of the 2 different designs. I prefer the DPMS lower. Unfortunately with DPMS shuttered by Cerebus, they are no longer making their fine product. However, there are some excellent sources out there building uppers that match DPMS lowers. Ex: ar15part.com
I believe - and I could be wrong - but both lowers were mil-spec but DPMS seemed to have the upper edge with different guys who I shoot with.
AR10/LR10's - I have never considered them to be "light" and easy to carry......
Most aftermarket parts are very standard and interchangeable. You should be able to use most any trigger group but some manufacturers do use proprietary components.
I have switched out a number of charging handles until I found one I liked - until I found one I liked better - It's kind of that way with the AR 15 or 10!!
Single ejector works well enough for me.
Depending on what you are planning on using for sights you may want to be sure to avoid a high rise upper. I could never get comfortable with the high rise upper.
From what I've read, the 6.5 Creedmoor is a hot straight accurate round. Has an outstanding B.C. It gets a lot of positive press. I have a buddy who shoots one and thinks it's the cat's meow. Me on the other hand have had years of experience with the .308 / 7.62x51. as a hunting round and target round. His AR is in 6.5 Creedmoor and mine's in .308. Great confidence in what it can do. While the .308 is not the latest glitz and glamor in the rifle world, it gets the job done. I'd stay with the .308. Others would disagree.

Good luck with your project - pictures when it's done would be fun!

 

I have a DPMS LR308 with a 16" barrel that I'm very fond of. Consistent hits out to 300 yds are not a problem with it. I've not tried it out any further than that, but I'm pretty sure it would be effective farther than that. I think it's just about perfect for carrying around in the woods. the longer barrels are too heavy for my old bones to pack very far. I also have another upper with a 22" 6.5 Creedmoor barrel. I like the round, and the recoil is slightly less than .308, but neither is too harsh. since I'm not a really long range shooter, the Creedmoor offers no advantage over the .308 for me.

 

(as this is also for my "SHTF Long Arms Collection") (quote)_
.308win./7,62x51 over any more older, newer or better caliber, because you could find .308 ammo anywhere, obtain a .308 from 30-06, 270, etc., if badly needed,
and a 150 fmj makes a neat hole in a iron horseshoe at 100 mts., with or without scope, thrashing away all the support frame where the horseshoe was nailed. (recycled L.C. 7,62 nato case

)_

 

(as this is also for my "SHTF Long Arms Collection") (quote)_
.308win./7,62x51 over any more older, newer or better caliber, because you could find .308 ammo anywhere, obtain a .308 from 30-06, 270, etc., if badly needed,
and a 150 fmj makes a neat hole in a iron horseshoe at 100 mts., with or without scope, thrashing away all the support frame where the horseshoe was nailed. (recycled L.C. 7,62 nato case

)_

AMAOF that is one of my main requirements for my SHTF Long Gun Collection. Be of a long tried and true as well as VERY popular and easy to find calibers that there will be a lot ofabandoned/ laying around/to be found/stolen/whatever in case of a "Total SHTF -D-Day/Democrat Takeover/Coup Scenario". And be some of the least expensive rds for "the bang for the bucks" so I can better afford buying a lot now too. I need me a new .22LR rifle too it seems. Should have kept the 2 old semi auto Rems I'd had since 12.....

As long as it's been produced and used I figure there'll be a lot of .308 WIN everywhere...those new/odd/wildcat calibers might get used up more quickly, besides they are more expensive too.

.22LR/5.56x45mm/30-30/45-70/ 7.62x39&51mm .303/.308/30.06/9mm/45acp and a few others are MOST popular and will be the best cals to own in a SHTF scenario IMO, because of availablity. But when those are gone the oddball cals will be next, IF you have a firearm to chamber them in.

 

Victor said to be 7lb 11 ounces, 16 inch barrel. Have a standard model barrel 22 inch M1A fitted into an surplus GI original style walnut stock with a GI sling weighs exactly 8 pounds, it also weighs this with the Springfield synthetic factory stock, the listed weight in the catalog is off. Spend a little time shimming the gas block and unitizing the gas cylinder, with selected ammunition or handloads should have a under 2 MOA rifle, mine are at about 1.25 moa, most issue/surplus fmj kinda sucks more like 3 inches. Anyway, this gives you the range, weight and accuracy you are looking for. Moving into the loaded and match models weight gets out of hand fast. Humped an XM21 with Art scope as a rock solid young infantry soldier, with no issues. These days I pick up my XM21 clone, heavy bugger, wondered how in the world did I ever humped this thing.

 

Just sold my Lr-308 AP4. Free float 16” carbine. Sub moa shooter, great rifle.
Short barrels are more accurate than long barrels. Velocity loss is a slight issue. Got about 2600fps. 150 gr hornady sst grouping .75” at 100yds at 2600fps will have no issues at all reaching 600yds or more.
6.5 creedmor is a nice round. Sub 500 yds a .308 will do anything it can do and more.
Most .308 ars will accept standard ar-15 stocks, triggers, hammers, grips.

 

Going from a 16 in barrel to a 20 in barrel will pick up about 100 fps with the 308 Winchester, IME.

For 500 yards, the 308 will be fine, provided you get the accuracy you want. I would check around and see what the match shooters are using for a barrel. Then get an upper built.

It is hard to build an all around rifle, but an 16 in AR in 308 with a good barrel and a high quality 1x-8x scope comes close, IMHO.

 

When you get into the higher end of barrels they are pretty much all excellent. Hart, Barnett, Shilen, Douglas Premium grade, Krieger, Criterion, Saturn, etc

 

Wouldn't trade my DPMS LR-308 for anything. I did lighten it up a bit with a free floated hand guard. Only have shot game and paper targets out to 100 yards with sub-moa accuracy--no range in my area that goes out beyond that. These rifles have a rep for outstanding accuracy up close and also--"out there aways". Many Youtube vids have been published on Oracle LR-308 accuracy and reliability. Remington recently shuttered DPMS due to Big Rs overall financial troubles. A pity since ARs are selling very well in my locale.

 

the way to find out out how far it will shoot is to try it, do you have a 1000 yd range to shoot at.
If that post a few days ago about the guy shooting 45-70 to 1900 yards is true, a 308 will shoot 500 yards all day long and 800-1000 with a bunch of practice
there used to be a warning on boxes of 22 ammo that said they will travel a mile

 

If you can live with a longer barrel you will get significant gain in velocity and less muzzle blast. A 16" barrel in .308/7.62mm NATO wastes powder in the form of muzzle blast and a fireball of unburned (wasted) powder. The 16" is sexy, but in MHO not practical. When the bullet uncorks at the muzzle the longer the barrel the lower the pressure and blast.

My 16" choice would be a 5.56mm..

Gene Stoner designed the .223 case based on being almost directly proportionate to the .30M1 (30/06) which is also proportionate to the .50BMG . The .222R is also proportionate to the .308/.7.62 NATO. Some say that those proportions are what made the 2 cartridges inherently accurate.

The gun should be designed around the cartridge and vice-versa.

JMHO 2 cents

AC

 

AR10 rifles were designed for 300-400yd ranges. The 7.62 NATO will travel or shoot much further. They are shot in 600 & 1000yd matches. I forget what sights on 7.62 MGs were marked.

 

Vietnam era M60's sights went up to 1,100 (feet/meters?)

The current M240's sight goes to 800 meters.

AC

 

I can’t even remember what m60 sight went to. I think I saw a picture of a 7.62MG that sight was marked to 1500meters. No doubt they will travel that far but not hold practical accuracy even for a beaten zone with a MG. Europeans were generous with back sight ranges. I think some of the C96 mausers were marked to 1000meters, nice shooting for a pistol even with stock attached.
In Korean War they used both 1919 Brn 30/06 and M2 50s for indirect fire at extreme end of their range. I don’t remember details it may have been a one time thing. Pulled the fat out of the fire at time when Chinese were doing human wave attacks. It was mentioned in training on MGs by instructors that were Korean vets, but I think it is documented too.

 

I remember reading somewhere that the 16" barreled AR 10's were accurate out to about 600 yards. But that was for target shooting, not hunting. I was looking for information at the time because I had purchased a 16" barreled AR 10 in 308. Not sure how effective a 308 round would be on game out to 600 yards. But I wouldn't shoot game out at that range, at least not out of my 16" barreled AR 10. The advantage, IMO, with the 16" barrel, is lighter weight and more maneuverability, especially in thick brush. I think both calibers are good, but I would pick the 308 due to its availability anywhere and everywhere. I am of the opinion that the 308 is a more versatile caliber. Been around for a long time. But either caliber will be a good choice whatever you choose.

 

Yes--When I go hunting I always use either a 308Win or a 30-06 rifle because you can always find those 2 calibers in the local small sporting goods stores. If you take something exotic like a 450 Bushmaster or a 444 Marlin and your ammo gets lost in shipment you are toast.

 

Alot of good feed back, for a SHTF only the most popular/common/military calibers like 308 are the only way to go, both to buy current ammo at good prices for stock piling, as well as a good trade item to have when things get tight. Have used the 308 for 46 years in both the military and civilian world. The M60, M240 and M14 have a 22 inch barrel for a reason, and my opinion is a barrel length of less than 20 inches is less than ideal in this caliber. Regarding stock piling, most commercial 308 hunting loads are at least reasonably accurate, and probably what you really want a lot of. Often standard factory 150gr soft point loads can be bought cheap after hunting season from the major supply houses offering some kind of coupon usually Federal. Current and somewhat aged military 7.62 FMJ rates from horrible to very good, most are mediocre. Wise to shop around and collect a box of many different FMJs and shoot for accuracy, stocking up on what works, wise to chronograph to. Picked up some Swiss surplus FMJ that was very accurate, but slow as pond water at 2500 fps out of a 22 inch barrel. I run handloaded 150gr FMJs and softpoints with a very similar BC using the same powder charge so there is no need for different dope, finding a balanced pair of loads like this takes a little work. Most folks like 168gr pills or heavier because they tend to offer better performance at extended ranges, but I use 150 gr pointed boat tails FMJ or soft points cuz I've slung so many of them out of a M60, M1A and hunting rifles, I know exactly how they behave and where they are going to go, with the idea of very good accuracy to 600 yards.

 

The 308 ar/ar10 I built has a 16” barrel and is lethal out to 500m with the right load. There are 2 main patterns, DPMS and Armalite.

DPMS pattern parts are much more commonly available. The difference lies in thread pattern of upper extension, barrel chamber differences and rail height (nowadays dpms high is getting to be the standard)

Any AR pattern trigger group will fit in a modern AR10/308 ar. Geissele will work great

I read on this thread that a 16” 308 barrel is only effective to 200-300 meters<img src="http://www.marlinowners.com/forum/images/smilies/huh.gif" border="0" alt="" title="Huh?" class="inlineimg" /> What lol. That is untrue.

6.5 vs 308 can bog you down for days deciding what to get. I personally prefer 308 due to ammo availability and cost. 6.5 is better at longer distances for target shooting. 6.5 can still be effective on animals, but IMO not the best for large game.
The trick to getting a perfectly tuned 308 ar is to get an adjustable gas block and correct buffer tube. I have found that on my 16” mid length barrel an A5 buffer tube with A5 buffer is perfect t and has resulted in 100% reliability through hundreds of rounds.

Lots of info can be found about this online, but what I’m telling you above has been learned by me from putting together multiple perfectly functioning AR10 rifles

 

The 308 ar/ar10 I built has a 16” barrel and is lethal out to 500m with the right load. There are 2 main patterns, DPMS and Armalite.

DPMS pattern parts are much more commonly available. The difference lies in thread pattern of upper extension, barrel chamber differences and rail height (nowadays dpms high is getting to be the standard)

Any AR pattern trigger group will fit in a modern AR10/308 ar. Geissele will work great

I read on this thread that a 16” 308 barrel is only effective to 200-300 meters<img src="https://www.marlinowners.com/forum/images/smilies/huh.gif" border="0" alt="" title="Huh?" class="inlineimg" /> What lol. That is untrue.

6.5 vs 308 can bog you down for days deciding what to get. I personally prefer 308 due to ammo availability and cost. 6.5 is better at longer distances for target shooting. 6.5 can still be effective on animals, but IMO not the best for large game.
The trick to getting a perfectly tuned 308 ar is to get an adjustable gas block and correct buffer tube. I have found that on my 16” mid length barrel an A5 buffer tube with A5 buffer is perfect t and has resulted in 100% reliability through hundreds of rounds.

Lots of info can be found about this online, but what I’m telling you above has been learned by me from putting together multiple perfectly functioning AR10 rifles

After I aquire this AR-10/.308 Win, I am considering a 9mm or .45acp Ar pistol, maybe an AR in 6.5 Creedmore AR too.

 

My Ruger SR762 has a 16" bbl and will easily shoot out to 400 yards. Though where I hunt the max range is about 200 yards. It is a 1 MOA rifle.

 

But they SR762 (x51) been discontinued by Ruger. FWIW it was gonna be my first choice in .308Win.

 

500 yds no problem, PM me I probably can hook you up with a good inexpensive trigger...

 

The 16" barrel will be real loud, but it will do the job well past 500 yards, as others have said. The .308 will give you a much longer barrel life than a 6.5 CM. This rifle is designed to be a light weight battle rifle or hunting rifle, at a price you can afford, and at a weight you can carry all day. Sounds like a good addition to anybodies gun collection. It will not consistently shoot apples off a fence post at 500 yards, but neither will a $2,000 dollar M1A. For a rifle like this, I would go with the .308 all day long.