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bgriggsjr said:
I am new to the black rifle market and I was wondering if someone could explain the difference between a heavy and light barrel fnar
Boy, I believe the rifles are identical in every way....except that the heavy barrel doesn't have the "flutes" that the FNAR light has.

Not sure what the weight difference is... but I am sure a review of rifle stats reveals that.

I wonder myself what the long-term difference in the barrels is? Perhaps if you intended firing a lot of rounds in a short time.... like if you were a front-line sniper that would likely have heavy use.... the heavy barrel would see less warping from high temperatures?
 

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Ick, which one do you have?

Also, for the heavy and light barrel question:
Heavy barrels should theoretically be more accurate, especially with a longer barrel, because they don't vibrate as much as a lighter barrel. The vibrations are a good thing to some extent because they help retain the accuracy of the rifle, but if the barrel vibrates too much, it could affect the rounds. I think with a 20" barrel you would be fine either way. Once you start getting out to the 26" range, you might start having to worry about it a bit. If you are going to carry for long distances, the lighter barrel would be the way to go, but if you are more of a range/benchrest shooter, I'd go for the heavy barrel.
 

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Boy, I don't know for SURE... but I believe the heavy and light version have the SAME barrel length.

I have a FNAR light.





It may be a bit hard to tell, but I think you can see the "noches" in the side of the barrel along the grip.
 

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Ick, I just checked out FN's site. They both have 20" barrels, but the light seems to be fluted much more than the heavy barrel. The heavy barrel appears to have light fluting on it. My guess is that they are pretty much the same, except the heavy is obviously a bit heavier. Also, the fluting on the light barrel would help dissipate heat a little faster than a conventional smooth barrel.

I'd say, if you like the fluting of the light barrel get it. If you don't, go for the heavy. It's just your preference and I really don't think you would be able to see a noticeable difference between barrels accuracy wise.
 

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hey are pretty much the same, when I got mine I have both of them in front me, one is just slighty heavier than the other, both are fluted, and both were the same price, I didnt see a difference except that the heavy barrel was a little thicker than the light. I just chose the light because it was un scuffed :)
 

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heavy vs light barrel

I went through this with my M1A. Out to 500 yards the groups were good, but beyond that the groups opened up.

I went with a medium heavy weight barrel and the groups tighten up again.

The way it was explained to me is that the heavier barrel absorbs recoil better and at long distances this aids in shot placement. There is less barrel movement with a heavy barrel too.

At Camp Perry anyone still shooting the M1A is using the medium weight barrel, which is very close to the heavy barrel in weight on the FNAR.

My bolt guns have heavy barrels and so I decided on the heavy barrel.

The rifle should be able to shoot well out to 800 yards. The heavy barrel will just make it more accurate at this distance. The .308 round is my long distance rifle and this FNAR shoots 175 grain bullets very well.

I shoot prone, because the rifle is just to heavy to get any accuracy doing it off hand. It is one heavy rifle.

The heavy barrel is accurate, but I agree the lighter barrel is easier to handle.
 

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I went through this with my M1A. Out to 500 yards the groups were good, but beyond that the groups opened up.

I went with a medium heavy weight barrel and the groups tighten up again.

The way it was explained to me is that the heavier barrel absorbs recoil better and at long distances this aids in shot placement. There is less barrel movement with a heavy barrel too.
So by the groups being good they were of a certain size or smaller and then past 500 they weren't of the certain size or smaller.?. I guess this begs the question: how much larger were the light barrelled groups at all the ranges fired?

What one person thinks is acceptable is not to another. Yes, aside from a bullet stability issue due to twist rates, two rifles differing in only barrel weight, the heavier one is going to possibly shoot better than the other. The possibly is simply due to the barrel not being able to be free floated on a gas operated semiauto. One rifle isn't simply going to shoot comparable groups out to a certain yardage and then throw more poor groups. That defies physics.

I have an FNAR in the heavy version and my buddy has one in the light version. The barrel is actually a different diameter which makes up for the 1 pound difference. We have yet to shoot them side by side, but I sort of wish I had the lighter version, so far. Granted, I'm happy that I got into a 308 for about a quarter of the money as I would have had to throw in the M1A's direction to get comparable accuracy.
 

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Yeah Stu0, it's a good topic. I have the light version because that was on sale. I'll be carrying this for hunting deer, bear and mountain lion in the Arizona militarized zone between I-10 and the border so 1lb lighter weight will be appreciated. Now that we don't have a magazine limit here in AZ I can carry 20 on board and be more on the level to the narco-terrorists our government has armed with AK-47s.

I would expect the heavy barrel to withstand heat better, but I have a bull barrel NEF 26" in .280 that has serious heat problems so just being big around and long doesn't solve everything :wink:. It would be nice to hear from people who have both the light and heavy 20" barrels and their experiences with accuracy especially for a full box of 20.
 

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Why is the Heavy Barrel more accurate at long distance?

The way it was explained to me is that the heavier barrel absorbs recoil better and at long distances this aids in shot placement. There is less barrel movement with a heavy barrel too.
I have been thinking about this thread and especially what wyominglarry said about the heavy barrel and recoil. They only way this statement makes sense to me is that the shooter flinches less with a heavy barrel. Off of a machine rest with a remote trigger, why would barrel weight matter if this is all it is. If the shooter can control their flinch, and there is no reason why they can't with a 10lb .308, what else is going on?

The "history of the FNAR" sticky post in this forum states that the heavy 20" has a longer effective range, so something is going on here, but I don't understand what it is. I would appreciate any enlightenment from the group.

Thanks in advance.
 

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In regards to longer effective range, just because it was written and put on the internet does not make it so. (I know you knew that.)

I too live in Arizona (west side of Phoenix). Maybe someday (once it cools down) we can get together and air the FNARs out at some distance. I had started on the hand loads for mine shortly before I realized there was a barrel issue. When I got it back from FNH, it was getting too hot to work up the loads so I'll resume again the temps cool down. (Looking forward to that).

Let me know if you are interested.
 

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Originally the 20" was available in a light and heavy and I think the 16" was as well. Also I believe all the barrels are fluted. I know the 20" light and heavy barrels are both fluted.

Didn't they stop producing one or the other (I assume they dropped the light) since there was only a pound weight difference between the 2... that was the explanation I heard for the rifles available for around $1k, "blowout" pricing.

Joe
 

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The standard barrel is straight from the muzzle all the way back to within a few inches of the chamber, where it tapers up quickly.
The heavy barrel tapers from the muzzle all the way to the chamber with a shallow taper.
They are the same diameter at the muzzle and most likely the chamber ends (muzzle end verified, chamber speculation).

A heavier barrel simply flexes less than standard barrel; there is less barrel whip, and less variation shot to shot. All barrels flex (vibrate, whip, whatever you want to call it) and the good ones do it the same amount every shot, making them more consistent shot to shot. The difference in consistency ("accuracy") between the FNAR standard and heavy barrels is small but it reveals itself more at greater distances once a minor deviation in flight path is amplified by aerodynamics and the wobble of the projectile.

Joe
 
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