Want a 6mm long range varminter that doesn't burn barrels.

[alf]

Probably not enough to worry about.

If it's for a short action 700, I'd do the 243, as it's a little more suited for the bigger bullets in a magazine.

 

[mattri]

Thanks again for all of the replies. I've been trying to keep up on new posts with my phone but I was just able to re-read everything and see that I missed a few. In order to cull the field a little lets use the following:

.243 (non AI)

6mm Rem (non AI)

6x47

Rifle will be short action but single shot, so mag length is not an issue.

 

[bozo699]

Mattri,
With those three choices I would rule out the 6mm because of brass choices, unless that's not a issue with you. Then it comes down to a personal choice I guess as both are a great cartridge, I have owned a multitude of .243's so for me and it being a new build I think It would be a 6X47L, know to be very accurate, great brass, and definitely capable of doing what you want it to do, good luck.
Wayne.

P.S if good brass ie. Lapua,Norma wasn't in your budget and Rem or Win was what you were planning on using I would probably opt for the 6mm rem, a little less brass streching then the .243 and a great round in itself.

 

[Jethrro]

The statement about the 20* shoulder causing lower barrel life mystifies though, doesn't the .308win have a 20* shoulder? I have heard of them going several thousand rounds.
Wayne.
[/quote]
I might be wrong but these 6mm wildcats cram a lot of powder down a small hole the 308 is a bigger hole hence longer barrel life. A slower burning powder can add to life of the barrel as well. Just what I've read and heard. Jethrro

 

[ChipEckardt]

You can have speed or barrel life, but you can't have both. It's a compromise. Everyone has a favorite, but there just ain't nothing new out there .....

Great post..and to the point.

Chip

 

[357Mag]

Don't intend to highjack this post.

Catshooter - No... I don't rely on just math for determining a good groundhog
killing combo. Practical field experience is applied, also.

I thought some sort of rudimentary guide line on KE, might be of some use.
The flip side is.... not everything works/gets the job done ( clean groundhog kills ), so a minimum KE level should help give a guy some idea of what's needed.
I don't have to have " red mist " effect, but DO desire kills to be clean.

As for the .243/.308 barrel life comments, I agree w/ Jethro.
Larger bullet diam of .308 compared to .243" gives pressure larger area to act upon, and is one contributor to potential for better barrel life of a .30 cal cae this size; over a 20* shoulder angled .243. That 20* shoulder angle puts the gas
"turbulence point " external to the case neck, one cause of lowered barrel life.

With regards,
357Mag

 

[bozo699]

Don't intend to highjack this post.

Catshooter - No... I don't rely on just math for determining a good groundhog
killing combo. Practical field experience is applied, also.

I thought some sort of rudimentary guide line on KE, might be of some use.
The flip side is.... not everything works/gets the job done ( clean groundhog kills ), so a minimum KE level should help give a guy some idea of what's needed.
I don't have to have " red mist " effect, but DO desire kills to be clean.

As for the .243/.308 barrel life comments, I agree w/ Jethro.
Larger bullet diam of .308 compared to .243" gives pressure larger area to act upon, and is one contributor to potential for better barrel life of a .30 cal cae this size; over a 20* shoulder angled .243. That 20* shoulder angle puts the gas
"turbulence point " external to the case neck, one cause of lowered barrel life.

With regards,
357Mag

Not being a smart ass here just trying to learn, so what your saying is a .243 with a 20* shoulder will have worse barrel life then a .243 AI with a 40* shoulder?
Wayne.

 

[mattri]

I'm trying to sort this out with Wayne- if I understand this correctly a plain jane .243 will have worse barrel life than either a .243AI or a 6mm Remm. Is that correct?

 

[bozo699]

Mattri,
I am trying to understand and sort it out myself, I was always with the understanding that barrel life was reduced with more powder and longer bullets
( longer bearing surface ) and some say boat tail bullets lead to throat erosion but the 20* shoulder thing is a first for me as well and I am waiting for a answer from Jethro and or 357mag, I am constantly learning new things on here.
Wayne.

 

[fordwrench]

in the same boat as you on this one. what im finding out is no one gun or cal is without drawbacks. it seems as though one could get by with a improved 6 br and a 6.5 47 or 6.5 284 for the longest shots. my next build will be a 6 284 HUNTING rifle shoot the barrel burners little and the user friend cals more often. btw my 6mm rem made load development and one pd trip and was missing 4 inch of rifling, no lie! about 1400 round in total.

 

[mattri]

As everyone has stated you can't get something for nothing and I understand that.
The question then becomes what do you get- and how much does it cost you?
If a .243, .243 AI and a 6mm Rem are so close in performance which is going to be the easiest on the throat, last the longest.
At the same time if one is head and shoulders above the rest re barrel life and gives up just a small margin of performance, less than going to say a 7mm or .308 etc- than again which would it be?

 

[CatShooter]

As everyone has stated you can't get something for nothing and I understand that.
The question then becomes what do you get- and how much does it cost you?
If a .243, .243 AI and a 6mm Rem are so close in performance which is going to be the easiest on the throat, last the longest.
At the same time if one is head and shoulders above the rest and gives up just a small margin of performance, less than going to say a 7mm or .308 etc- than again which would it be?

With cases that are so close, it will solely depend on how you load it.

 

[bozo699]

Catshooter,
I am in agreement with your statement, What is your thoughts on barrel wear concerning a 20 degree shoulder as has been mentioned on here, I value your thoughts on the subject.
Wayne.

 

[CatShooter]

Catshooter,
I am in agreement with your statement, What is your thoughts on barrel wear concerning a 20 degree shoulder as has been mentioned on here, I value your thoughts on the subject.
Wayne.

It is a "theory" that has never been proven.

There is intuitive logic that argues that the longer neck of the 6mm Rem is protective to the throat (barrels don't "wear out", they burn out), and the thinking is that the short neck of the 243 is rougher on the throat.

I think that it "might" have merit, but as I said before, no one has done "real" test on it, so it is pure rumor at this point.

But the way you load it, and how you shoot it, will have more bearing on the barrel life than the case shape.


Meow.

 

[bozo699]

Catshooter,
I am in agreement with your statement, What is your thoughts on barrel wear concerning a 20 degree shoulder as has been mentioned on here, I value your thoughts on the subject.
Wayne.

It is a "theory" that has never been proven.

There is intuitive logic that argues that the longer neck of the 6mm Rem is protective to the throat (barrels don't "wear out", they burn out), and the thinking is that the short neck of the 243 is rougher on the throat.

I think that it "might" have merit, but as I said before, no one has done "real" test on it, so it is pure rumor at this point.

But the way you load it, and how you shoot it, will have more bearing on the barrel life than the case shape.


Meow.

Thanks Catshooter,
I agree with your last comment 100% and your answer to my question sounds rational and reasonable and I am satisfied with it, thank you.
Wayne

 

[mattri]

Are they really that similar?
Obviously if someone was irresponsible enough they could shoot out any barrel in no time at all.
If loaded and shot in a reasonable way will barrel life be indistinguishable from round to round?

 

[CatShooter]

Are they really that similar?
Obviously if someone was irresponsible enough they could shoot out any barrel in no time at all.
If loaded and shot in a reasonable way will barrel life be indistinguishable from round to round?

"Are they really that similar? "

Yes...

The 6mm Rem holds 54.3 gr of water.
The 243 Win holds 52.7 gr of water.

So, for all practical purposes, they are the same.

"If loaded and shot in a reasonable way will barrel life be indistinguishable from round to round? "
Yes - loaded to the same pressure, with similar bullets, the barrel lives will be the same.

The killer of barrels is heat, pressure, and bullet transit time.

If you want a given bullet to travel at a given speed, it is better to shoot a larger case at a lower pressure - than a smaller case at a higher pressure.

"Obviously if someone was irresponsible enough they could shoot out any barrel in no time at all. "

Someone does NOT have to be irresponsible to burn out a barrel - one buys a .220 Swift, a 6mmx284, or a .264 Win Mag, to reach out further than a 222, a 6mmx45, or a 6.5BR Rem.

But with careful loading, the barrel lives of these "beasts" can be extended quite a long time.


Meow.

 

[MarkS]

mattri
I have been down this road before. I have had the 6AI 6MM 243, 243AI 6CX, and have stopped at the 6BR. I like a 12 tw barrel and shot 70gr Blitzkings running 3500 f/s. I have many one shot kills on Va groundhogs past 600yds. The big 6's will not run with the 6BR as far as accuracy.

Mark Schronce

 

[Jethrro]

I'm trying to sort this out with Wayne- if I understand this correctly a plain jane .243 will have worse barrel life than either a .243AI or a 6mm Remm. Is that correct?

Correct from what I have read. There are physics involved with this end of reloading that I have yet to understand. An example of a round that is hard on barrels is the 223 Win super short Mag. "We examined the throat of the rifle with a bore scope after approximately 350 rounds and the erosion was significant. This cartridge is hard on barrels." Quoted from the Hornady reloading manual. Back to the lots o powder down a small hole and a lot of heat.
There are a ton of variables that will affect the life of the barrel. It just boils down to what you want in the end. Jethrro

 

[357Mag]

Bozzo699 -

Please read your PM's.

Regards,
357Mag