[Vincine]

I’m looking at a couple of RRA’s 5.56/.223s to punch paper out to 300 yards in the spring.

Both have heavy chrome molly barrels with 1:8 twists and promise .75 MOA. One is a 16”and 7 pounds, the other is 20” and 8.4 pounds. All other things being equal, what does an extra 4” get me marksmanship wise, if anything?

They also offer a 24”, 1:8 at 9+ pounds with no increase in accuracy. Why?

[pagj17]

Well, you get yourself 1.4 pounds more weight, and a higher velocity, which leads to slightly better ballistics, and some would say "a more accurate" barrel.
It all comes down to personal preference.

[Yunus]

I'm not knowledgeable enough to speak scientifically on this subject, I can only pass on what I have read. Accuracy from a barrel is more than just how long it is. How sturdy it is is a major factor as well. Length will give you higher velocity but also worse harmonics assuming the girth of the barrel doesn't increase as well. I tried to find the article that I have seen on the internet that had a good matrix of testing done to show this but I could not find it anywhere.

I would go with the 16" one because it will be easier to carry without bumping into things.

Barrel Length v. Accuracy Test

[Vincine]

Originally Posted by pagj17

Well, you get yourself 1.4 pounds more weight, and a higher velocity, which leads to slightly better ballistics, and some would say "a more accurate" barrel.
It all comes down to personal preference.

Yes, but I guess the question is; Is the slightly better ballistics even going to be apparent on targets between 100 and 300 yards?

(300 yards is the longest range available to me.)

[Yunus]

Originally Posted by Vincine

Yes, but I guess the question is; Is the slightly better ballistics even going to be apparent on targets between 100 and 300 yards?

(300 yards is the longest range available to me.)

Don't forget the other factor in accuracy of a gun, the shooter. More weight, especially when it's far away from your body is going to make it harder to hold on target.

[Vincine]

Originally Posted by Yunus

Don't forget the other factor in accuracy of a gun, the shooter. More weight, especially when it's far away from your body is going to make it harder to hold on target.

Yeah, okay, so the additional accuracy provided by the length, if any, is more than given away if one is hand holding.

[Yunus]

Originally Posted by Vincine

Yeah, okay, so the additional accuracy provided by the length, if any, is more than given away if one is hand holding.

It will vary shooter to shooter. I have a Howa 1500 in .223 with a 24" varmint barrel on it. From a rest this thing will shoot 1/2 MOA. In my hands unsupported standing, I shoot 1.5-2 MOA. I am the weakest link in the accuracy of that gun.

[Vincine]

Originally Posted by Yunus

It will vary shooter to shooter. I have a Howa 1500 in .223 with a 24" varmint barrel on it. From a rest this thing will shoot 1/2 MOA. In my hands unsupported standing, I shoot 1.5-2 MOA. I am the weakest link in the accuracy of that gun.

Wow!

I think I just got it. The 16” for mobile shooting, the 24” is bench rest, and the 20” is the compromise.

So, either get the 20”, OR get the 16” now, and get a 24” barrel in the admittedly unlikely event I max out on the 16”.

Does that sound like a plan?

[JonM]

Depends on if your using open sights or an optic.

My opinion:

Open sights you want as much sight radius as you can. The more weight you have forward of the reciever the steadier and more predictable the wobble of unsupported shooting becomes. With a proper sling free floated barrel and enough but not too much weight a unsupported position becomes almost as solid as shooting off the bench.

24 inch barrels are way too front heavy for my tastes especially once you put a sling or optic or bipod on it. I like 20" because im not losing any real effectiveness past 300 yards and i have enough weight and balance to make good shots.

16" i dont really like since its a compromise to a true m4 and rifle length mainly due to idiotic federal restrictions on short barrels and the loss of balance for longer shots. They work fine off a rest but try and balance one off hand and its a mess. The loss of a lot of sight radius is a huge no go for me.

If i wasclearing buildings 16" might be tempting but i really dont see that happening.

I wish rra offered a pencil barrel rifle length upper really fast light weight and still has full sight radius.

[Vincine]

Originally Posted by JonM

Open sights you want as much sight radius as you can.

Ah, right, I forgot about open sights.

Originally Posted by JonM

The more weight you have forward of the reciever the steadier and more predictable the wobble of unsupported shooting becomes. With a proper sling free floated barrel and enough but not too much weight a unsupported position becomes almost as solid as shooting off the bench.

Really? Good to know, thanks.