Most accurate round...with 20" barrel?

[Goat-roper]

Okay, gunslingers, gnat-knockers, brass-packers....I've seen lots of targets on here, heard lots of data, but I haven't heard your opinion on what you think is the most accurate round out of a "carbine" or short barrel. Chime in.

 

[PickettSFHunter]

hmmm let me think about this.....I dont have a clue. I dont know why a shorter barrel would change anything as far as which calibers. Most often it is not the caliber that defines accuracy, it is the weapon and how it is made.

 

[megalomaniac]

All rifles will be more accurate with a shorter barrel over a longer barrel (all other things being equal).

That being said, what you are looking for is a caliber which is capable of using case capacity (ie burning the powder) in a short barrel.

All the .308 family (.243, .260, 7-08, .308) are quite accurate and are still quite efficient even with a 20" barrel.

 

[PickettSFHunter]

Why would you think a rifle would be more accurate with a shorter barrel?????

 

[4onaside]

All rifles will be more accurate with a shorter barrel over a longer barrel (all other things being equal).

That being said, what you are looking for is a caliber which is capable of using case capacity (ie burning the powder) in a short barrel.

All the .308 family (.243, .260, 7-08, .308) are quite accurate and are still quite efficient even with a 20" barrel.

I realize that my response does not address the specific question asked by Goat-roper, but they are more "efficient" in a 22", 24" or most of all a 26" barrel. For every inch that you chop off from 26", you lose quite a few fps(velocity), which in turn gets back to the efficiency of a round, doesn't it?

 

[PickettSFHunter]

you are correct 4onaside. If you really want a long range rifle your talking around a 30 inch barrel.

 

[4onaside]

you are correct 4onaside. If you really want a long range rifle your talking around a 30 inch barrel.

I realize that anything beyond 26" inches becomes impractical from a handling standpoint(although I once owned a model 95 chilean mauser that had a 29" barrel, which I cut off to a more practical length). Most all of your ballistics tables use 26" barrels to arrive at their figures. I own two 26"rs, one of which I just bought for my next year's(hopefully, LOL) prarie goat hunt. However, at the ranges that most of us shoot for whitetails all of this is really immaterial, 18, 20, 26, or whatever.

 

[megalomaniac]

Steven,

shorter barrels are more inherently accurate because they are stiffer. Same reason a #8 contour is more accurate than a #2 contour. Less barrel vibration as the bullet travels through the bore.

Again, this is all other variables being equal.

 

[megalomaniac]

All rifles will be more accurate with a shorter barrel over a longer barrel (all other things being equal).

That being said, what you are looking for is a caliber which is capable of using case capacity (ie burning the powder) in a short barrel.

All the .308 family (.243, .260, 7-08, .308) are quite accurate and are still quite efficient even with a 20" barrel.

I realize that my response does not address the specific question asked by Goat-roper, but they are more "efficient" in a 22", 24" or most of all a 26" barrel. For every inch that you chop off from 26", you lose quite a few fps(velocity), which in turn gets back to the efficiency of a round, doesn't it?

Ahh, that's the rub...

ALL cartridges will lose velocity as you shorten the barrel. BUT, some cartridges will experience a disproportionate drop in velocity with barrel shortening compared to other cartridges. Thus the 'efficiency' concept. The .308 family will retain a larger percentage of its original velocity when chopped from 26 to 20 inches over much larger cases. Although the larger cases will still be travelling faster than the 308 at 20", they will have lost disproportionately more velocity.

The concept of lengthening the barrel is similar as well. Most cartridges have an optimum barrel length, and going beyond that the gains in fps/inch of barrel begin to diminsh significantly. Most hunting cartridges operate at most efficient (velocity versus the inconvenience and decreased accuracy of a longer barrel) lengths of 24-26". Exceptions are the ultramags which operate at maximum efficiency of barrel lengths of 28-30"

 

[megalomaniac]

Here's some real numbers, although different barrels:

15" encore pistol 7mm-08 140gr BT, 47g re 19......2500 fps
22" rem 700 7mm-08 140gr BT, 47g re 19......2725 fps

I forget where I saw it, but there's a chart on the web where a fellow actually started with a 26" barrel and cut it off at 2" increments and recorded the velocity after each shortening job. If I recall, he ended up with around 25 fps/inch decrease in velocity with that particular cartridge.

 

[PickettSFHunter]

Why do long range shooters use very long barrels?

 

[TiminTN]

Yeah, why?

 

[megalomaniac]

Why do long range shooters use very long barrels?

??? For the extra velocity, of course.

But they don't build 28" ers on a #2 contour.

 

[PickettSFHunter]

Well I may have learned something.

 

[TAS]

Yeah, why?

LOL

 

[Whelen Man]

All rifles will be more accurate with a shorter barrel over a longer barrel (all other things being equal).

That being said, what you are looking for is a caliber which is capable of using case capacity (ie burning the powder) in a short barrel.

All the .308 family (.243, .260, 7-08, .308) are quite accurate and are still quite efficient even with a 20" barrel.

Don't forget my 358 Winchester now! It's my favorite hunting rifle in a 20 inch barrel. It's a good combination of size, range, and efficiency in a handy barrel length. I would limit it's use to 300 yards though. In the shorter barrels the less the expansion ratio the greater the efficiency . A lot of powder needs a lot of barrel and vice versa. I vote for the 308 or 358 Winchester.

(Of course now I'm leaving out the 338 Federal which should be equally good with the right bullets.)

 

[DaveTN]

For people who use open sights longer barrels are more accurate because they have a longer sight radius.

The long and short of whether "the barrel� is more accurate is simply physics and metallurgy. The more stable barrel will be more accurate regardless of its length.

 

[4onaside]

you are correct 4onaside. If you really want a long range rifle your talking around a 30 inch barrel.

I realize that anything beyond 26" inches becomes impractical from a handling standpoint(although I once owned a model 95 chilean mauser that had a 29" barrel, which I cut off to a more practical length). Most all of your ballistics tables use 26" barrels to arrive at their figures. I own two 26"rs, one of which I just bought for my next year's(hopefully, LOL) prarie goat hunt. However, at the ranges that most of us shoot for whitetails all of this is really immaterial, 18, 20, 26, or whatever.

I DO NOT own ANY rifles with 26" barrels, much less two of them! This statement has long since past, but I thought about it in my car and realized that I have apparently slipped over the edge. I own two with 24" inch barrels. Any longer and I probably couldn't hold them up! Now that I have corrected this mis-speak I can slip back into my coma.LOL