barrel life .243 vs 6mmbr

[nra-for-life]

Hi everyone,

I was consulting with a gunsmith today about the prospect of having a custom rifle built. He told me something that sort of raised a red flag...

I told him I would like the rifle to be chambered in 6mmbr and he told me that i should go with .243 instead. I told him that I was worried that .243 would have a much shorter barrel life than the 6mmbr. He told me that If I was shooting the same weight bullets, the 243 would outperform the 6mm in all aspects, cycle better if i decided to go with a mag feed, and the barrel life would be very comparable....

I have never owned a 6mmbr, but i thought that they were a quite a bit better on barrels than 243. Thoughts???

 

[Browningguy]

In my opinion the .243 is much tougher on barrels than a 6BR. But I went with .243 anyway.

 

[Gunner75]

I pushed 107's and 115's out of a 28" Barlien (243) at 3,000 plus fps for 2500 rounds, then rechambered and used that barrel to FF 6mm Crusaders. I pulled it after shooting the FF rounds at 3,000 total. Give or take 100 rounds overall.
The barrel still shot better than MOA by far.

Use good barrels

The 6BR I would think would have better barrel life than a 243, but I haven't shot out a 6BR yet!

 

[goosebrown]

Interesting article here on overbore cartridges, the theory is that the ratio of case size to bore can be used to determine thoat erosion and barrel ware. The 6mm br has about 1/3 less case capacity to bore than 243. By their numbers the 6mmbr is in the easy on barrel category and 243 is on hard on barrel category.

http://www.accurateshooter.com/technical-articles/overbore-cartridges-defined-by-formula/

 

[fdshuster]

nra-for-life (me also, since 1965); I burned out 3, 243 chamberings, all in approx. 1400 rounds. A Douglas chrome moly & 2 Shilens. They were very accurate for about the first 800 rounds, then started throwing unexplained wild shots with the number increasing to the point they would not hold moa with 5 shots. An increase in copper fouling also became a problem.

Checkout the article on this site's home page, technical articles, concerning overbore cartridges, and note where on the list the 243 is.

One of my 6BR's is now approaching 2000 documented rounds fired, and as seen with my Hawkeye borescope, there is not a trace of firecracking in the throat area.

The 243 barrels started to show the beginnings of firecracking at 400 rounds.

243 is an excellent round if you "need" it. For many of us, the 6BR is all that is needed to punch a hole in a piece of paper with accuracy that is very close to the 6ppc. JMO & experience.

 

[K22]

My Remington Model 700 stainless has 3,582 rounds through it. It still shoots under 1 MOA which is adequate for a hunting rifle. It believe the 243 is one of the finest overall hunting cartridges ever designed. Shot a doe this season, lung shot, she walked ten yards and fell over.

However it sounds like target shooting is your game. If so the decision is quite simple, select a cartridge designed specifically for target shooting with the least overbore; the 6mmbr fits that criteria perfectly.

 

[Scott Harris]

I'm a dedicated 243WIN shooter, but I am switching to 6BRX for my F-Open Caliber. I expect the following benefits:

1. Out to 600 yards, I expect the 6BR to give me better scores due to its' superior accuracy: maybe just a few points here and there, but an improvement nonetheless.
2. 500-1000 rounds better barrel life. How can 8 grains less powder on every shot not produce better barrel life?
3. Similar velocities with the 6BRX: around 3000 fps with a 105gr bullet.

The 243WIN is a fine round, but the only advantage it has over the 6BR is ability to push the 115 gr bullets and magazine feeding. The 6BR has the advantages described above: you'll have to decide what is important. It does sound like your gunsmith has an unwarranted bias: maybe he does not have a 6BR reamer.

 

[nra-for-life]

It does sound like your gunsmith has an unwarranted bias: maybe he does not have a 6BR reamer.

ROFLMAO, that caught me off guard, almost spit my drink out.

 

[Rustystud]

For target shooting accuracy the 243 Winchester will last about 1600 rounds. For target shooting accuracy the 6mmBR will last 3500-4000 rounds. This is for 600 yards and in. This is using a premium grade barrel. The 6mmBR has a slight edge on inherent accuracy,and economy. I have shot both of them extensively. There is a reason for the 6mmBRX and Dasher. They give the 6mmBR just enough advantage to shoot 1000 yards without the loss of ecconomy. Both shoot almost as hard as the .243 Win.
Nat Lambeth

 

[WyleWD]

I was consulting with a gunsmith today about the prospect of having a custom rifle built. He told me something that sort of raised a red flag...

I told him I would like the rifle to be chambered in 6mmbr and he told me that i should go with .243 instead. I told him that I was worried that .243 would have a much shorter barrel life than the 6mmbr. He told me that If I was shooting the same weight bullets, the 243 would outperform the 6mm in all aspects, cycle better if i decided to go with a mag feed, and the barrel life would be very comparable....

I have never owned a 6mmbr, but i thought that they were a quite a bit better on barrels than 243. Thoughts???

Is this going to be a target rifle of some kind or a antelope/deer/hog hunting rifle? WD

 

[nra-for-life]

Is this going to be a target rifle of some kind or a antelope/deer/hog hunting rifle? WD

Mostly printing but also some varmint. no deer or other medium-big game.

 

[jerrschmitt]

I have two of each. Although, my .243s are Ackley Improved versions. One 243 and one 6mmBR are 8 twist and the other two rifless are 14 and 13 twist. I do a lot of prairie dog shooting and can't imagine being without both. (all).

 

[nra-for-life]

.....One of my 6BR's is now approaching 2000 documented rounds fired, and as seen with my Hawkeye borescope, there is not a trace of firecracking in the throat area.

The 243 barrels started to show the beginnings of firecracking at 400 rounds.

243 is an excellent round if you "need" it. For many of us, the 6BR is all that is needed to punch a hole in a piece of paper with accuracy that is very close to the 6ppc. JMO & experience.

what is firecracking???

 

[fdshuster]

The surface of the throat looks like a dry lake bed in Arizona. Caused by the intense heat ( some say well over 2000 degrees F.) of the burning powder. More powder in a small bore diameter, like a 22 CHeeta, and you have very short barrel life.

When firecracking becomes extreme, little chunks of barrel steel begin ripping out of the surface of the throat, leaving holes in the surface that quickly fill up with copper. The reason copper fouling is usually a sign that the barrel is nearing "the end".

With my Hawkeye borescope I have watched it happen beginning with a newly chambered hand-lapped barrel(s) to the point where it looks like a sewar pipe.

Check out some of the advertisements in the magazines by Gradient Lens Corp., that have the round pictures showing what you will see in the bore, when using a borescope. These pictures are telling the ugly truth!

 

[Webster]

The 6BR definitely has a much better bore life than the 243. The 30BR beats everything for bore life. The 6BR shoots flat enough for varmint hunting. I have mine free bored for the lighter BR bullets 58-70). I seldom shoot more than 350 yds. Most of the hay fields in Ohio are no more than 400 yds. wide. I'll take .350" groups over .75" groups any day. The 243 is a little flatter shooting but it has shorter barrel life and it isn't as accurate. You will spent more money trying to find good loads for the 243. Take your pick.
From the Hodgens website. Both 70 gr bullets.
6BR 34.0 grains of Varget 3342 fps
243 42.5 grains Varget 3594 fps