- Thread starter John1999
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Most people shoot much shorter (16-22") with excellent accuracy.
those people are idiots. They are the types that tell you how well their 16" .308s shoot at long range but you'll never see them at a match or beyond the 25 yard range.
I just got a 28" installed on my 308 yesterday hope it is accurate.
Spent good money for it.
PSE EVO 60 Lbs.
Blacked out
Spent good money for it.
PSE EVO 60 Lbs.
Blacked out
I can tell you how accurate my 16" gun is or that I really do shoot long range with it but more to the point............"those people are idiots." A good barrel is a good barrel, in a good gun will be accurate and more velocity is well............ more velocity.
Really is that simple.
I know for 300wm, the magic number is 24 1/4 -- For 308, isn't it in the low 20's?
It depends on the bullet weight, twist rate and what type of powder you are using. My buddy that got me into long range shooting (that bastard) won several Palma matches with a 30" 14 twist 308 barrel shooting 155gr Scenars, he can fairly consistently hit a head sized target at 1000 yards with iron sights.
D.ID,
I have no doubt your short barrel shoots nice groups at 100yards, and that you have no trouble hitting large targets at extended distances.
However, the fact of the matter is that your short barrel is not and never will be a match winning barrel no matter who makes it.
I invite you to go to a local precision match in your area. You know, not a "tactical" match, but a match where the goal is to hit a 1/2MOA bullseye for several (usually 3 consecutive) 20-shot strings and report back on how well your short barrel did. You may want to bring a hack-saw with you tho as i'm sure those people running 30-32" barrels are gonna want to cut down their barrels down to the length you are running.
I'm not condeming short barrels, they have their place...close quarters applications, hunting in thick brush where shots rarely exceed 100-200yards etc. However, i'm pretty sure the OP got this long barrel for match and precision applications. And for that, the folks telling him his barrel wont be accurate because it's long are idiots and don't know a thing about accuracy or long range shooting.
I have no doubt your short barrel shoots nice groups at 100yards, and that you have no trouble hitting large targets at extended distances.
However, the fact of the matter is that your short barrel is not and never will be a match winning barrel no matter who makes it.
I invite you to go to a local precision match in your area. You know, not a "tactical" match, but a match where the goal is to hit a 1/2MOA bullseye for several (usually 3 consecutive) 20-shot strings and report back on how well your short barrel did. You may want to bring a hack-saw with you tho as i'm sure those people running 30-32" barrels are gonna want to cut down their barrels down to the length you are running.
I'm not condeming short barrels, they have their place...close quarters applications, hunting in thick brush where shots rarely exceed 100-200yards etc. However, i'm pretty sure the OP got this long barrel for match and precision applications. And for that, the folks telling him his barrel wont be accurate because it's long are idiots and don't know a thing about accuracy or long range shooting.
Every caliber/load has a barrel length where, eventually, at least statistically, it reaches a point of diminishing return...Thus a "magic number".
When I was building my 300wm, for my loads, I did some heavy math and 24 1/4 was optimal...Again, that # is based on my specific loads (H1000, 220 Sierra, Hornady brass)
In 300wm, especially if you use H1000, if you go shorter than 20" the powder only reaches @96% burn. In 24, it's like 99.4%...For 24 1/4 if I remember right, it comes out to 99.6ish.
In 308, I seem to remember it being between 20" and 22" for optimum burn/velocity.
That's not to say you can't go longer...It's just that for us normal folk, there is a point where it becomes unnecessary.
For benchrest, there's still a diminishing return but, clearly, most of them prefer much longer barrels.
Guess my rifle won't shoot either. 
it's a 28" Bartlein 1:11.25 twist on a stiller Tac 30 in an AICS.
First time I ever shot it. This was at 200 yards with fgm 175's.
it's a 28" Bartlein 1:11.25 twist on a stiller Tac 30 in an AICS. 
First time I ever shot it. This was at 200 yards with fgm 175's.
I've never understood the draw of chopping a barrel on a "long range" gun. Yeah, we all like to fiddle with our guns, and customize, to our tastes, but when shortening a barrel drops velocity, I say no thanks. I spent a lot of change on a 300 Win Mag, to gain precious velocity. A lot of guys load HOT rounds [IE over book Max} to gain velocity. I'm certainly not going to chop a barrel and lose velocity. If I want a "brush gun", I'll buy a brush gun. But I won't , then, call it a long range gun. I've got a S&W 44 Mag that will hit, at 100, but it's got an 8 in barrel. Long for a pistol, and not an easy carry gun, but I used to carry it. I don't see it as a long range gun. A good barrel will shoot, long or short. Velocity is what I look for.
Personally I have watched the trend of shorter and shorter barrels on 308 rifle platforms and I think some people are going too short because it's the trendy thing to do these days. Unless you reload, your 308 ammo will be optimized for something longer than 20 inches. Even if you do reload a 16 in barreled 308 is going to be very LOUD and it won't have the velocity of a 24+ inch barrel.
Nothing wrong with a shorter barrel. It has certain advantages over a longer one if you have the right use case. For those of you who love your shorter barrels just please be willing to admit that there are some things (velocity) that will be better with a longer barrel.
Nothing wrong with a shorter barrel. It has certain advantages over a longer one if you have the right use case. For those of you who love your shorter barrels just please be willing to admit that there are some things (velocity) that will be better with a longer barrel.
My 308 TRG 22 with a 26"barrel and my 308 AIAW with a 24" barrel both consistently shoot groups under 0.3 moa with my best 5 shot 100 yard groups under 0.2 moa.
I wasn't saying it won't be accurate or worth-while...I also wasn't saying longer is wrong.
What I said was that, per velocity and physics, there's a diminishing return at a certain barrel length depending on the load.
It very well may be that your 26" is useless due to the fact that past 24" there's no velocity gain because all of the powdered is burned...So if you were to cut 2" off your barrel, accuracy would NOT diminish at all...*I don't know your loads so, please don't actually do that*
Barrel length is really all about powder burn...If you're shooting a 20" Win Mag with H1000, you're only going to achieve @ 2500 fps compared to a 24" with H1000 that gets 2800fps...Beyond 24" it may not be worth the longer barrel because 99.6% of the powder is already burned.
Again, for benchrest shooters, there's a reason to have a longer barrel because the diminishing return doesn't matter...For us, "average joe's", there's a point where it's not worth having a longer barrel based on your load...So, do the math and make a decision.
Masked,
You are referencing theory in your argument. I'm referencing real-life application.
You keep referring to powder burn and some magical optimal barrel length. That argument is bullshit.
Your optimum barrel length will change with bullet weight, powder type, powder charge, outside air temperature, elevation etc. See? It's nice on paper but it doesn't work in real life.
The "optimal" barrel is the one that is suitable for the application. As long as that application is not kicking in doors or hunting/shooting in close, tight quarters, a short barrel ain't it.
You are referencing theory in your argument. I'm referencing real-life application.
You keep referring to powder burn and some magical optimal barrel length. That argument is bullshit.
Your optimum barrel length will change with bullet weight, powder type, powder charge, outside air temperature, elevation etc. See? It's nice on paper but it doesn't work in real life.
The "optimal" barrel is the one that is suitable for the application. As long as that application is not kicking in doors or hunting/shooting in close, tight quarters, a short barrel ain't it.
Where do you get that this is "theory"? It's physics.
Litz has proven velocity varies by barrel length until diminishing return as has practically every shooter in history. This is seriously, COMMON SENSE.
If you have 208 amax behind 70gr of H1000 going down an 18" tube...It's proven that only @95% of your powder is burned thus, there's a lower velocity...That works in real life because it's this thing called physics, you know...Math?
I said the "magic number" was typically the length by which you achieve maximum powder burn...This is indicated by a higher velocity? And I said that there's a diminishing return, because you know...There is? Thus why 18" barrels see a significantly LOWER velocity with the same exact load than LONGER barrels? Regardless of the outside temperature.
...Temperature and elevation are variables we cannot control. Barrel length and load are 100%.
Whether or not accuracy is affected is the theory and the only theory within the 4 corners of this discussion. Powder burn and diminishing returns are a fact of life, IE physics and thus, will //always// be a reality.
Not trying to be a douche but my back ground is chemical engineering. I'm very familiar with physics, physical chemistry, and combustion reactions.
You are arguing Theory, not real life. In theory, things work out the way you and other have outlined...you can even run a program such as Quickload to tell you then powder burn is supposedly complete...however, all these results are based on calculations which are in turn based on a bunch of ASSumptions for variables out of your control...
I don't want to further derail this thread, but you mentioned Brian Litz,
Well, have you ever seen Bryan shoot? Know what his Long range rig is? Yeah, it ain't a short barrel anything...he runs what everyone else runs: a long barreled rig to extract the maximum potential from the load and then some.
Fact is optimal barrel length is a function of things that are out of your control...powder type (and its associated chemistry which changes from lot-to lot), powder charge, weather, elevation etc. All these things factor in and are difficult to ESTIMATE especially in the calculations your arguments rest on...we make up for it in real life by having a barrel longer than you think you might need, not shorter.
Same thing in my job as an Engineer...you calculate how much say surface area you need and you ADD some extra to account for unknown variables...
In long range shooting the extra barrel length is your fudge factor for the known & unknown unknowns...it's also convenient that it adds velocity (helping you buck the wind as this separates the top guys from everyone else) and provides you with a longer sight radius that increases one's accuracy (if you shoot iron sights like I do)
Capiche?
You are arguing Theory, not real life. In theory, things work out the way you and other have outlined...you can even run a program such as Quickload to tell you then powder burn is supposedly complete...however, all these results are based on calculations which are in turn based on a bunch of ASSumptions for variables out of your control...
I don't want to further derail this thread, but you mentioned Brian Litz,
Well, have you ever seen Bryan shoot? Know what his Long range rig is? Yeah, it ain't a short barrel anything...he runs what everyone else runs: a long barreled rig to extract the maximum potential from the load and then some.
Fact is optimal barrel length is a function of things that are out of your control...powder type (and its associated chemistry which changes from lot-to lot), powder charge, weather, elevation etc. All these things factor in and are difficult to ESTIMATE especially in the calculations your arguments rest on...we make up for it in real life by having a barrel longer than you think you might need, not shorter.
Same thing in my job as an Engineer...you calculate how much say surface area you need and you ADD some extra to account for unknown variables...
In long range shooting the extra barrel length is your fudge factor for the known & unknown unknowns...it's also convenient that it adds velocity (helping you buck the wind as this separates the top guys from everyone else) and provides you with a longer sight radius that increases one's accuracy (if you shoot iron sights like I do)
Capiche?
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FWIW . . . .
My understanding is:
(1) Powder burns VERY fast. It is usually burned before the bullet moves very far down the barrel.
(2) the bullet is accelerating from the time it leaves the case mouth until it leaves the muzzle.
(3) once the bullet exits the muzzle, it begins to decelerate.
(4) a longer barrel allows the bullet to continue accelerating.
An example is a drag race--from the starting line to 1/4 mile mark, the car accelerates. At 1/4 mile, the foot comes off the gas, and it slows down.
if the race was 1/8 of a mile, the car would be going slower when the foot came off the gas. If the race was 1/2 a mile, the car would go a little faster than at 1/4, but the mechanical limitations of the car keep it from accelerating forever.
BMT
My understanding is:
(1) Powder burns VERY fast. It is usually burned before the bullet moves very far down the barrel.
(2) the bullet is accelerating from the time it leaves the case mouth until it leaves the muzzle.
(3) once the bullet exits the muzzle, it begins to decelerate.
(4) a longer barrel allows the bullet to continue accelerating.
An example is a drag race--from the starting line to 1/4 mile mark, the car accelerates. At 1/4 mile, the foot comes off the gas, and it slows down.
if the race was 1/8 of a mile, the car would be going slower when the foot came off the gas. If the race was 1/2 a mile, the car would go a little faster than at 1/4, but the mechanical limitations of the car keep it from accelerating forever.
BMT
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Well, I'm sorry but, you are a douche because you're wrong...We're not discussing the finite details of a load, we're discussing a concept which has hypothetically been proven over and over and over and over and over and over and over and over again.
The Truth About Barrel Length, Muzzle Velocity and Accuracy | The Truth About Guns
BBTI - Ballistics by the Inch :: Home
http://honors.usf.edu/documents/thesis/u82488180.pdf
There are THOUSANDS of documented, statistically proven articles based on the fact that barrel length effects velocity due to powder burn...So again, your "facts" are wrong.
Of course no 2 loads will ever be the exact same, thus we have averages...But, per VOLUME and volume alone, this entire equation is 100% proven by simple math. If 70gr of powder cannot be burned over a distance of 18" then you lose velocity.
I don't comprehend how, as a chemical engineer, we're even having this discussion...
Again, I don't care if 1gr of powder makes a 1 fps difference, that's not the discussion.
The OP asked if barrel length makes a difference in accuracy...That is a THEORY due to harmonic "imbalance" which could absolutely vary by steel (we have no evidence of this), by mix, by twist...Maybe the foundry operator farted and let it stay in 1s too long...There is no certainty of accuracy but, there IS a certainty of barrel length and it's direct correlation to velocity VIA powder burn.
All right Masked. You win. I loose. Ya happy?
OP, sorry to have crapped all over your thread. Your 28" barrel will be just fine. Let us know how she shoots after you've developed a load.
OP, sorry to have crapped all over your thread. Your 28" barrel will be just fine. Let us know how she shoots after you've developed a load.
It really isn't ... fastest rifles in the world don't use powder or burn anything at all in the barrel (aka Light gas guns)
Muzzle velocity is direct product of pressure curve VS friction VS time.
In a cartridge firearm:
pressure curve = how intense and how long is the burn
friction = bullet weight, surface, twist rate
time = barrel length
With modern propellants even small cases like 6BR have enough residual pressure (well past the "burn) to overcome the friction and increase the velocity with longer barrel, even past 30".
In competition every bit of speed helps with wind uncertainty (winning vs loosing).
Long barrels come a the cost of size, weight AND stiffness.
There is no "right" answer for all situations; there is a double standard though - both F-class and tactical shooters have precision rifles, but they are for different situations and will not be competitive vice versa. While F-class shooters will easily admit that a 18 pound rifle will not do well shooting off a fence post in a time crunch; tactical shooters can't get it through their thick skulls that 18 inch rifle is not good for chasing 1/2MOA X-ring in the wind.... /rant off
...
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I was just calling you a douche because you coined it, first. -- No ill will here, brother. Also, knowledge is power, no harm, no foul.
I was never saying a longer barrel is bad...My purpose was to explain that the OP doesn't need 28" to get a full powder burn...That's more/less likely achieved at around 24-26".
If I were the OP, again I did this with my 300wm, do the math, break down optimum barrel length and depending on your belief (Long vs. short) cut it or don't...I cut both of mine...Clearly it depends on the rifle's intent and him.
Stiffness, harmonics...There are 100s of factors in accuracy so, who knows...Your confidence per shot is going to equate to more than the barrel length = accuracy, theory, anyway!
Oye...But, within time there's also a diminishing return.
Again, I never argued against barrel length -- I argued that there was/is a provable diminishing return for us "common folk"...I do not define "common folk" as F-class or bench-rest shooters.
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There is still lots of pressure in the barrel after the powder is burned, but while the bullet is still in the barrel. That makes it go faster. The optimal barrel length issue is not a speed issue, but long-range shooting is a speed issue. The faster the bullet gets going, the less it will get blown sideways by the wind. That is relevant to the OP's posts. A long-range target shooter wants minimal wind drift, so he/she wants maximum velocity. Past maybe about 31-32 inches, it's a waste; but the OP's proposed 28" barrel is all gain (in velocity) and no waste, and can be just as accurate at short range as anything else he is likely to shoot. Go for it, OP! You can always cut off some barrel later, but you can't add any.
Jim
Jim
Um,
Firstly, thanks for not being easily offended.
It's a little difficult to argue with you cause you are now back-pedaling.
Anchoring your barrel selection to something such as a highly theoretical and changing variable such as powder burn is a terrible way to select a barrel length. This isn't a college physics course. There are no massless, friction-less ropes, and you don't get to ignore other factors that affect powder burn.
The end of powder burn does not mean there is not a pressure difference between the back of the bullet and the front of it (delta-p = unbalanced force = movement of the bullet towards to lower pressure side = more bullet velocity).
Again, the barrel stiffness angle is a red herring used by internet commandos to justify their short barrel length. If you've ever seen a long range competition rifle (you clearly haven't), you'll notice that the barrels are sometimes up to 1.5" thick...sometimes with a taper at the muzzle to accommodate the mounting of iron sights/non-magnified apertures. These barrels are very stiff and difference in stiffness between a short barrel and a longer barrel can effectively be ignored.
For all intents and purposes, the barrel lengths in common use in competition 28-32" are no where near the point of diminishing return.
I now understand your point of view (no experience shooting a bullseye type match at any distance of significance) but wish you weren't so strident in arguing something you have no experience with.
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Oh, really?
So, let me get this straight. First you call my fact, a theory. Then it's proven statistically (You were proven wrong). Then it's proven again just, by the scientific explanation rather than the CK (common knowledge) version and you claim, that because of this belief (Another fact, that there is a diminishing return), I have no experience shooting any distance of significance?
Wow, douche-baggery to the max.
I've hinged my argument to velocity which is a direct factor resulting from powder burn or, time as it was so eloquently put.
Again, there is no real correlation between barrel length and accuracy; that in and of itself, is the theory (Which is actually, ironically, discussed at length in the Truth About Guns study).
Clearly it depends on the OP's intentions of the rifle but, were I simply "target shooting" with a 308, I'd still keep it around 24".
Masked,
Here's what i now know about you
1. You don't know what a theory is.
2. You don't know how a theory is applied in real life or accounted for.
3. You've never shot competitively... at long range...or at any distance of note
4. You make no attempt get educated before hitting the "reply button"
Good day Sir!
Here's what i now know about you
1. You don't know what a theory is.
2. You don't know how a theory is applied in real life or accounted for.
3. You've never shot competitively... at long range...or at any distance of note
4. You make no attempt get educated before hitting the "reply button"
Good day Sir!
OP, I'm sure your barrel will work for your application. There are so many variables involved in LR shooting that one theory or fact is really no better than another. It's all about application though. If your shooting long range for groups, most tend to run barrels on the longer side. Although most tactical shooters still shoot long range, with shorter barrels but with the purpose of only needing to hit a target; not shoot a tight group. Best part about a 308 is, it's very forgiving on many levels. Best of luck and happy shooting
To masked,
In the truth about gun article you quoted, it is proven the longer barrel, higher bullet velocity. That will give you longer super sonic flight distance. In the usf paper you quote. The barrel was cut in field and recrowned with hand tool. I am not sure if that is a very good control condition. In addition, in the USC paper, it also show the velocity and barrel lenth relationship. Also, at the end, the accuracy vs barrel length result, it is showing, grouping for length >24" is better than barrel with <20" with my eye est. Sorry, I will agree with the other s base on your posted links.
In the truth about gun article you quoted, it is proven the longer barrel, higher bullet velocity. That will give you longer super sonic flight distance. In the usf paper you quote. The barrel was cut in field and recrowned with hand tool. I am not sure if that is a very good control condition. In addition, in the USC paper, it also show the velocity and barrel lenth relationship. Also, at the end, the accuracy vs barrel length result, it is showing, grouping for length >24" is better than barrel with <20" with my eye est. Sorry, I will agree with the other s base on your posted links.
I never actually said anything in regards to accuracy beyond the fact that it's entirely theoretical.
I simply said that there's a statistical proven relationship versus barrel length and velocity. If you want to quantify that relationship as burn time, okay but, the fact is that the longer the barrel, more powder is burned, thus more pressure = more velocity.
I also said that, eventually, that velocity reaches a point of diminishing returns.
Again, I never spoke about accuracy beyond the fact of theory. Also, what's interesting is the TTAG study disproves the USC paper in regards to accuracy...Because as others have said, there's far too much involved for us to actually test accuracy. Velocity -- That's easy.
My theory is that your head is stuck so far up your asshole you can't see straight. Guess I was right.
The 28", 10 twist barrel I used for the 600yd Wisconsin regionals match last fall seems to work ok.
Longer barrel doesn't mean more powder is burned since powder can be completely burnt, and pressure can be static or dropping - as long as the pressure force is greater than the friction the bullet will continue to accelerate. Your example applies to setup that don't achieve a complete burn already (like the 24" 300WM - small steps up or down make HUGE velocity jumps).
More pressure doesn't really mean more velocity either - it's all about how much pressure is applied and for HOW LONG: it's the area under the pressure/time CURVE.
As long as the projectile doesn't explode from over-spin, velocity never reaches a point of diminishing returns - the more velocity the better. Even 1fps faster is still faster, still closer to target in uncertain wind. There are "practical limits" in rifle size as well as "practical limits" for targets sizes; e.g. 1/2MOA disadvantage is not as important on 2MOA target VS 1/2MOA target.
.
Large targets like rock chucks at 800 yards? This debate is boring and redundant.
Shorter barrels are stiffer and so are shorter actions. So what? I have long action- long barrel guns that are way more accurate than I will ever be making it a mute point. A pointless theoretical solution to a non existent problem.
. Longer barrels produce more velocity FOR a given cartridge.
My 24" WSM will out run your 30" 308 win, So what? You gotta have everything a given cartridge has? If that were true we would all be sporting 34"+ barrels.
Given my limited use for the 308 and the fact I would not even have a 308 except I had a 300 blackout barrel that sucked re-chambered. It works well, shoots farther than I would trust a 308 for real work and is handy, So what?
longer barrels=Faster, Shorter barrels=light and convenient. Diminishing returns are a compromise in either direction and as long as it fits your needs....................................SO WHAT?
P.S. 20 shot strings serve no purpose EXCEPT 20 shot strings..........just a waist of ammo in the real world.
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Generally accepted engineering practice is that buildup or decay functions attain "equilibrium" (aka point of diminishing returns) after 5 time constants or half lives (f=1-(1/2)^(time/half-life). The key relationship for this problem is between velocity and barrel length. Unfortunately, velocity is impacted by a number of parameters such as bullet weight, charge weight, powder burn rate, barrel friction coefficient, drag, etc. If you had the time to write a computer code, one could calculate the contribution of all of these factors, perhaps neglecting extremely negligible parameters and lot-to-lot variations.
To get a rough idea, one could develop a relationship using powder burn rate (since it is reasonable to accept that powder burned is equivalent to increase in bullet velocity) and assume that you are at about five half lives (or saturation) at >96% of all powder consumed by the time the bullet exits the muzzle - the so called "magic number", which would really be only valid for a particular bullet/powder/charge weight/primer configuration. I have never seen any of this, and I doubt that there is an extensive tabulation of this data publicly available; it would be nice if there was because it would be more straightforward to determine the tradeoff between going with an 16" or 24" 308 Win by doing a tabular comparison of empirically derived data (if someone knows, please share).
IMO, since no tabularized compendium exists this leaves you with a few choices:
- accept a barrel length based on a constraint set by the intended use (needs to be operator like and tacticool)
- either purchase or write software that can develop a relationship to compute velocity increase vs barrel length for a given bullet, charge weight, and powder type and select barrel length based on the outputs of the model (I've never met anyone who has done this, but I would do it if I had convenient access to an already written software program)
- go with the length that most the preponderance of factory and custom rifle builders to with because field use feedback and potentially some ballistic data supports the length used (seems like every factory 7mm Rem Mag or 300 WM barrel has a 26" length ... )
- go with a length that is certain to exceed the needs and provide a competitive edge to the intended use and then some, such as a 31" palma competition barrel that needs every bit of velocity possible to launch 155s to 1000 yds.
OP, since many factory 308 Win barrels are between 20-24", it's safe to presume that your longer barrel, while less maneuverable, will provide more muzzle velocity than standard factory 308s. Against F/TR or palma shooters, it would be in a level field. Against a 16" 308, it will outperform at distances >400+ yds. Against calibers with inherently better ballistics than a 308, well you get the point. I would challenge your friends to explain the relationship or correlation between barrel length and accuracy; you'll likely get a blank stare because it doesn't exist.
To get a rough idea, one could develop a relationship using powder burn rate (since it is reasonable to accept that powder burned is equivalent to increase in bullet velocity) and assume that you are at about five half lives (or saturation) at >96% of all powder consumed by the time the bullet exits the muzzle - the so called "magic number", which would really be only valid for a particular bullet/powder/charge weight/primer configuration. I have never seen any of this, and I doubt that there is an extensive tabulation of this data publicly available; it would be nice if there was because it would be more straightforward to determine the tradeoff between going with an 16" or 24" 308 Win by doing a tabular comparison of empirically derived data (if someone knows, please share).
IMO, since no tabularized compendium exists this leaves you with a few choices:
- accept a barrel length based on a constraint set by the intended use (needs to be operator like and tacticool)
- either purchase or write software that can develop a relationship to compute velocity increase vs barrel length for a given bullet, charge weight, and powder type and select barrel length based on the outputs of the model (I've never met anyone who has done this, but I would do it if I had convenient access to an already written software program)
- go with the length that most the preponderance of factory and custom rifle builders to with because field use feedback and potentially some ballistic data supports the length used (seems like every factory 7mm Rem Mag or 300 WM barrel has a 26" length ... )
- go with a length that is certain to exceed the needs and provide a competitive edge to the intended use and then some, such as a 31" palma competition barrel that needs every bit of velocity possible to launch 155s to 1000 yds.
OP, since many factory 308 Win barrels are between 20-24", it's safe to presume that your longer barrel, while less maneuverable, will provide more muzzle velocity than standard factory 308s. Against F/TR or palma shooters, it would be in a level field. Against a 16" 308, it will outperform at distances >400+ yds. Against calibers with inherently better ballistics than a 308, well you get the point. I would challenge your friends to explain the relationship or correlation between barrel length and accuracy; you'll likely get a blank stare because it doesn't exist.
Masked, just out of curiosity, how old are you? Because your taking a topic that means jack shit and whining like a fucking teenager. You calling people "douche bags" and such is just plain out dumb and will GET YOU NOWHERE in trying to get your point across. Actually I've been laughing my ass off at you using the phrase "douche baggery". WTF does that even mean? Do us all a favor , and go back to playing with your Bryan Litz action figures.
Sorry. went to get popcorn! What happened?
To Masked,
You posted in #12
"In 308, I seem to remember it being between 20" and 22" for optimum burn/velocity."
According to your link, the 28in barrel has higher velocity than 22in barrel. So your memory is incorrect. I am pointing out, based on your statement you posted, that means at 22", the power is complete burned or nearly complete burned thus anlonger barrel will not gain higher velocity. From my reading of your supporting articles, looks like the diminish return will be beyond 30" barrel.
You posted #17
"It very well may be that your 26" is useless due to the fact that past 24" there's no velocity gain because all of the powdered is burned...So if you were to cut 2" off your barrel, accuracy would NOT diminish at all..."
Again, your statement does not match your reference.
Your post #33 to my response.
"I simply said that there's a statistical proven relationship versus barrel length and velocity. If you want to quantify that relationship as burn time, okay but, the fact is that the longer the barrel, more powder is burned, thus more pressure = more velocity. "
Actually, no. Given a specific cal and cartridge, there is a max powder load. Any more powder will not burn effectively. Any more powder will reduce bullet velocity. Based on your post #17, you are contradict yourself because the powder has complete burned by 24", but muzzle velocity still increase after 28".
Please do not use big words like "statistic" or "physic" too freely because you don't know who might have advance degree on this forum.
You posted in #12
"In 308, I seem to remember it being between 20" and 22" for optimum burn/velocity."
According to your link, the 28in barrel has higher velocity than 22in barrel. So your memory is incorrect. I am pointing out, based on your statement you posted, that means at 22", the power is complete burned or nearly complete burned thus anlonger barrel will not gain higher velocity. From my reading of your supporting articles, looks like the diminish return will be beyond 30" barrel.
You posted #17
"It very well may be that your 26" is useless due to the fact that past 24" there's no velocity gain because all of the powdered is burned...So if you were to cut 2" off your barrel, accuracy would NOT diminish at all..."
Again, your statement does not match your reference.
Your post #33 to my response.
"I simply said that there's a statistical proven relationship versus barrel length and velocity. If you want to quantify that relationship as burn time, okay but, the fact is that the longer the barrel, more powder is burned, thus more pressure = more velocity. "
Actually, no. Given a specific cal and cartridge, there is a max powder load. Any more powder will not burn effectively. Any more powder will reduce bullet velocity. Based on your post #17, you are contradict yourself because the powder has complete burned by 24", but muzzle velocity still increase after 28".
Please do not use big words like "statistic" or "physic" too freely because you don't know who might have advance degree on this forum.
I have 308s of different lengths. Anywhere from a 16" being built right now at GAP, to 2- 20"ers, and a 26". All have their place and limitations.
OP, your BBL if done right will be extremely accurate. Most all the F-Class guys are running 28+". IF you see yourself shooting inside 600 yds a lot and maybe you will be moving around then the shorter bbls seem to be a little better.
If your using a suppressor and you know the limitations of what you want to use your rifle for the my 16" looks pretty promising.
HUH? Since it will be weighted down with Suppressor, PVS 22/thermal, IR Illumination, sling, bipod, and maybe another mag or two and I might use the cover of darkness to get into a closer shot then I say they all have their place.
A rifle is a tool and you must select the best tool for the job, are there some that will be more versatile? Sure, but you still need to choose accordingly.
OP, by target shooting do you mean like F-TR?
And you will also see that people in diferent locations will set their guns up much differently than other parts of the country.
If I could only have one I would go somewhere around 22-24" I think but that's because I wont be competing. If so I'll run what I brung and shoot against myself.
And BTW, my 26" and my 20" are both very accurate rifles. My 16" on the way probably will be too. Since I plan on using it on yotes and such and a truck gun out to 500ish I think it will be nice. I have other options for other needs.
OP, glad to hear you got you something to shoot. Don't let anyone hold you back. Don't be scared, get you a good load and get to practicing. You will find yourself light years ahead of everyone left behind nitpicking. Make it work.
Best of luck to you sir.
OP, your BBL if done right will be extremely accurate. Most all the F-Class guys are running 28+". IF you see yourself shooting inside 600 yds a lot and maybe you will be moving around then the shorter bbls seem to be a little better.
If your using a suppressor and you know the limitations of what you want to use your rifle for the my 16" looks pretty promising.
HUH? Since it will be weighted down with Suppressor, PVS 22/thermal, IR Illumination, sling, bipod, and maybe another mag or two and I might use the cover of darkness to get into a closer shot then I say they all have their place.
A rifle is a tool and you must select the best tool for the job, are there some that will be more versatile? Sure, but you still need to choose accordingly.
OP, by target shooting do you mean like F-TR?
And you will also see that people in diferent locations will set their guns up much differently than other parts of the country.
If I could only have one I would go somewhere around 22-24" I think but that's because I wont be competing. If so I'll run what I brung and shoot against myself.
And BTW, my 26" and my 20" are both very accurate rifles. My 16" on the way probably will be too. Since I plan on using it on yotes and such and a truck gun out to 500ish I think it will be nice. I have other options for other needs.
OP, glad to hear you got you something to shoot. Don't let anyone hold you back. Don't be scared, get you a good load and get to practicing. You will find yourself light years ahead of everyone left behind nitpicking. Make it work.
Best of luck to you sir.
^^^^^^^What he said^^^^^^^+1
Good stuff.... I feel dumb now.... I am going to go bang some rocks together while I listen to the Paris Hilton album on YouTube......
It is definitely NOT true.
Look no further than Palma shooters if you want to know how well longer barreled 308 rifles shoot.
The longest Palma barrel I remember was 32".
Not saying there haven't been longer but 32" is the longest I personally saw at a match.
I converted my old Palma rifle to a tactical rifle by adding detachable magazine bottom metal and cutting the barrel back from 30" to 26".
Still shot great with either barrel length till the barrel finally shot out last year.
A Palma barrel contour will probably not set any 1000 yard F-Class world records because the contour is a bit light due to weight restrictions.
