Preferred barrel weight for "all-around" AR

[Racewin]

If you had just one AR to "do everything," which would you choose? Assumptions...16" length, good quality, nitrided 4150.

 

[Suck My Glock]

The AR system is already lightweight, so I don't mind suffering a little bit of a weight penalty for a thicker barrel.

However, a stiffer barrel can be lightweight if it is fluted.

That's why all my builds in the last 20 years have used fluted barrels.

The challenge, however, has been to find a STRAIGHT fluted barrel with all the other features I want. So many people have gone nuts with fancy-pants spiral fluting or diamond fluting, or some manufacturers only flute forward of the handguard.

I'm always on the lookout for a straight-fluted, 1/9 twist, nitride finish, with a Wylde chamber. I can find that rather easily in years past with 1/7 or even 1/8 twist, but it seems no one likes 1/9 anymore. Or,...for some stupid whacky reason, manufacturers cut flutes on the barrels now AFTER nitriding the barrel, to give it that supposedly sexy 2-tone look,...completely destroying the all-weather protection nitride provides.

And fluting promotes quicker cooling as well, by creating more surface area for heat to radiate off from.

 

[That Guy]

The AR system is already lightweight, so I don't mind suffering a little bit of a weight penalty for a thicker barrel.

However, a stiffer barrel can be lightweight if it is fluted.

That's why all my builds in the last 20 years have used fluted barrels.

The challenge, however, has been to find a STRAIGHT fluted barrel with all the other features I want. So many people have gone nuts with fancy-pants spiral fluting or diamond fluting, or some manufacturers only flute forward of the handguard.

I'm always on the lookout for a straight-fluted, 1/9 twist, nitride finish, with a Wylde chamber. I can find that rather easily in years past with 1/7 or even 1/8 twist, but it seems no one likes 1/9 anymore. Or,...for some stupid whacky reason, manufacturers cut flutes on the barrels now AFTER nitriding the barrel, to give it that supposedly sexy 2-tone look,...completely destroying the all-weather protection nitride provides.

And fluting promotes quicker cooling as well, by creating more surface area for heat to radiate off from.

“ The challenge, however, has been to find a STRAIGHT fluted barrel with all the other features I want. So many people have gone nuts with fancy-pants spiral fluting or diamond fluting, or some manufacturers only flute forward of the handguard.”

Cuz’ if’n you aim to sell gun stuff to professionals you’ll only make pennies (if that) from them, but if’n you target the gun media and amateurs you’ll make dollars,

 

[Suck My Glock]

Cuz’ if’n you aim to sell gun stuff to professionals you’ll only make pennies (if that) from them, but if’n you target the gun media and amateurs you’ll make dollars,

Yep,...that nail just got its head bashed in.

 

[Old Jeff H]

I'm always on the lookout for a straight-fluted, 1/9 twist, nitride finish, with a Wylde chamber. I can find that rather easily in years past with 1/7 or even 1/8 twist, but it seems no one likes 1/9 anymore.

Curious about the preference for 1/9. I've (perhaps incorrectly) been thinking for years that a 1/8 is the most versatile. Do you mostly shoot lighter stuff?

 

[Suck My Glock]

I'm always on the lookout for a straight-fluted, 1/9 twist, nitride finish, with a Wylde chamber. I can find that rather easily in years past with 1/7 or even 1/8 twist, but it seems no one likes 1/9 anymore.

Curious about the preference for 1/9. I've (perhaps incorrectly) been thinking for years that a 1/8 is the most versatile. Do you mostly shoot lighter stuff?

My experience has been that if you never shoot 55 grain or lighter, yes, 1/8 or 1/7 is fine. And most 55 grain stuff will function in those twists,...usually low pressure .223 (compared to higher pressure 5.56). But I have seen full pressure 5.56 55-grainers shred themselves in flight from that fast a spin. And since 1/9 stabilizes everything up to 69 grain just fine - and since I never shoot heavier than that - for me, the 1/9 rate has the greatest adaptability to as many varieties of ammo in either .223 or 5.56 that I might need to feed the rifle with in a pinch.

Now, if I had enough of a budget to stockpile 77grn heavy ammo for my exclusive supply, perhaps then I would bother building a rifle with a 1/7 to handle that. But I'm of the opinion that I want my rifle to feed the widest variety of feed pellets it is likely to get, and heavy grain stuff just ain't on the list.

 

[That Guy]

The only reason the military went with 1/7 in the first place was to stabilize tracer bullets. Now I think tracers are really cool and a very useful cartridge to have on hand but in reality very few people who own 5.56 rifles have more than a 100 rounds and dang few have ever attempted any serious shooting with them. I’ve never had any 55 grain bullets shred running down my 1/7 barrels but then I only shoot M193 ball. I suspect some of those HP or SP “varmit” bullet jackets aren’t as tough as FMJ.

 

[BigNate]

I did some digging - and what I found was that the difference between very light and very heavy barrels is pretty negligible.
Larue 16" Ultralight Profile barrel - 1lb 10.5 oz - or 26.5 oz
Colt 16" "government profile" barrel - 1 lb 12 oz - or 28.0 oz
Colt 16" "HBAR" barrel - 2lb 3.4 oz - or 35.4 oz

So - the difference between the ultralight barrel and a heavy barrel in the AR platform is 8.9 ounces. For me - as long as I'm not buying the gun for a VERY specific purpose that demands minimal weight - like I need to carry it to the top of Mount Everest and then engage in room clearing activities where a hundredth of a second slower movement around a corner might mean my life - I'm going to opt for the heavy barrel. The difference between a 1.5 - 2.0 MOA gun and a .75 - 1 MOA gun gets pretty noticeable when trying to put rounds on target at 500+ meters - whereas the extra 8.9 ounces is not going to make much difference in 99% of the situations that you will find yourself in after the beginning of the zombie apocalypses.

That said -the real answer to the question:"If you had just one AR to 'do everything,' which would you choose..." is - "I'd choose a well built AR-10 in 7.62X51"

 

[Old Jeff H]

I'm always on the lookout for a straight-fluted, 1/9 twist, nitride finish, with a Wylde chamber. I can find that rather easily in years past with 1/7 or even 1/8 twist, but it seems no one likes 1/9 anymore.

Curious about the preference for 1/9. I've (perhaps incorrectly) been thinking for years that a 1/8 is the most versatile. Do you mostly shoot lighter stuff?

My experience has been that if you never shoot 55 grain or lighter, yes, 1/8 or 1/7 is fine. And most 55 grain stuff will function in those twists,...usually low pressure .223 (compared to higher pressure 5.56). But I have seen full pressure 5.56 55-grainers shred themselves in flight from that fast a spin. And since 1/9 stabilizes everything up to 69 grain just fine - and since I never shoot heavier than that - for me, the 1/9 rate has the greatest adaptability to as many varieties of ammo in either .223 or 5.56 that I might need to feed the rifle with in a pinch.

Now, if I had enough of a budget to stockpile 77grn heavy ammo for my exclusive supply, perhaps then I would bother building a rifle with a 1/7 to handle that. But I'm of the opinion that I want my rifle to feed the widest variety of feed pellets it is likely to get, and heavy grain stuff just ain't on the list.

Makes sense! Thanks.