Barrel length?

[WaterDog]

Because I’m not real sure, tell me how the length of the barrel effects energy, velocity, accuracy, etc?

The reason I ask is as I look at different makes and models of rifles the barrel length varies from 20” to 26”.

:smile:

[Gus Orviston]

The way I understand it is, that the longer the barrel the more time allowed/available for gas expansion, thus higher pressures, which can result in higher velocities.
The goal is that the gases are done building pressure as the bullet leaves the end of the barrel or a bit more, allowing it to build pressure just beyond the barrel allows for consistency from shot to shot. If you ended building pressure early the deviation would result in poor repeatable accuracy... kind of like not pulling a bow string back to the same anchor point. each shot has a different amount of energy....

That said accuracy is a function of repeatability of pressures, not necessarily longer barrel lengths, although 24" is better than 4", 26" isn't guaranteed to be better than 24" on length alone.

The round you are shooting has a huge part to play as well, magnums will typically not be as accurate as the smaller calibers.

Pick a caliber you will enjoy shooting, is reasonable for the game you are hunting, you don't mind buying ammo for or reloading, whatever your criteria, and if the weight is what you want to carry.

I am sure there are others here with more information

[ 10-31-2002, 04:13 PM: Message edited by: Gus Orviston ]

Barrel length (to a point) only determines velocity. A longer bbl doesn't give higher pressure but gives the pressure (push) for longer, thus higher velocity.

[Lured In]

Rifle or Shotgun?

Rifles it depends on the round, but as was mentioned primarily effects velocity. On most ballastics tables from Remington, Winchester or others it will list barrel length. Several outdoor magazines have dones studies on this as well.

Shotguns, it only effects how well the gun 'points' (accuracy). 26" barrels are easier to swing, 28" barrels generally are more accurate.

[SeanD]

the appropriate barrel length in a hunting rifle depends on a few different things, the most important being the round it shoots. Magnum calibers that use slower burning powders need longer barrels in order to burn all the powder and get maximum velocity. Which is why a 300 win mag usually comes with a 26 inch barrel, and a .308 might come with a 20". You can get faster velocity with longer than stock hunting barrel length, but every extra inch after that gives you less added velocity. I went the other way, i have a 30.06 with a 19.5 inch barrel, 4.5 inches shorter than most factory barrels, and i use a faster burning powder to make up for it. The result is a very light and short brush gun that still gets 2850 fps with 150 gr handloads. And it is more accurate than my factory 300 win with a 26 inch barrel. go figure :smile:

I guess ill add that i wouldnt sweat the barrel lengths too much. There are standards for calibers, and if a maker offers different barrel lengths in the same caliber, its because they are marketing to offer variety, like a featherweight or compact. Just buy the rifle that fits your need, and the barrel length will be fine.

[ 10-31-2002, 11:27 PM: Message edited by: SeanD ]

[WaterDog]

Thanks guys. This is helping. :smile:

I've decided I'm going to get a new gun for deer/elk. I'm going to get a 30.06. I'm used to carrying a short rifle (30-30 Marlin) so I'm leaning towards a 20 or 22 inch barrel. I'm going to start putting in for an E. OR elk tag next year so this gun will be used here on the westside for deer as well as east.

SeanD, what rifle are you shooting? Your info is exactly what I'm looking for.

[tailchaser]

Don't forget the important part of a longer barrell. It allows for more twist of the bullet in a controlled enivronment before it leaves the gun. The more twist you have the more accurate it's going to fly. This can change though with the loads you're shooting. With an .06 you should be fine with a standard length, but when you get magnums and pushing larger bullets you need a longer barrel to create an accurate rifle.

tc

[kodiakfisher]

Remember for the most part it is NOT the rifle that is the largest part of the equation in accuracy it is the the round.

Example go buy any rifle and buy six different boxes of ammo, different mfg and different bullet weights. I promise you you will find two boxes that don't shoot worth a darn, one or two boxes that shoot really nice and two that are okay. Once you have the round figured out BTW this is why so many people load there own. To adjust burn times and bullet weights to match what shoots great out of their rifle. Once you have the round dialed in you can look at things like glass bedding and other things done to improve rifle accuracy.

OR you can buy the browning with the BOSS and tune your rifle to your round this is what I have done and I have shot a three shot group with all holes touching @100yds with witnesses 165gr bullet. I then tried it with 185gr and couldn't shoot less than 2.5".

Kodiakfisher

[SeanD]

Waterdog, my 30.06 is actually an old 03a3 military thats been "sporterized". If i had to buy one for your situation, id probably go with an 30.06 too, and get a 22 inch barrel like what you'd find on a savage hunter or a remington ADL. I probably wouldnt go any shorter than that with the 30.06 unless you are going to handload, or youll shoot flames out the end of your barrel at night with factory rounds. Looks cool, but just wasted powder. Then throw a Vari X III 2.5-8 on it and your good to go.

Kodiakfisher is right on too. Buy some boxes of several premium loads like partition, grandslam, etc, and shoot them all to see what shoots best.

[ 11-01-2002, 09:41 AM: Message edited by: SeanD ]

[Mtn Man]

The length of the barrel only needs to be as long as it takes to burn the powder, any longer and you start to slow the bullet down. There are many variables, such as powder quantity and burn rate, bullet design, twist, humidity, etc. All of these will effect the accuracy of the gun and can be tuned by barrel length, this is what the BOSS system tries to do.

The main advantage to going with a longer length barrel is the added accuracy it provides by increasing the sight radius, but that only applies to open sights.

In short there is no right length, just barrel lengths that fit certain situations. With the 30-06 I would generally stick with the shorter length. I have heard that the BOSS system can really help with fine tuning a gun, it can be added to almost any gun by a good gunsmith.

A BOSS just adds 4 usless extra inches to your barrel.
You can do the same thing that a BOSS does (harmonics) by playing with your loads.
I tend to shoot shorter barrels on my rifles but my 7mm Rem Mag has a 26" and my 300 Win Mag a 24" barrel. The rest of my rifles (the bolt actions) have 18"-21" barrels with the exception of my 7mm-08 Ruger #1 that has a 24" barrel. Most of my rifles have had barrel work and are very accurate (better than I am).
The shorter barrels handle brushy situations well. I used the 7mm Rem and 300 Win for Mt. Goats where there was no brush so the barrel length didn't matter.

[Gus Orviston]

Keta, thanks you said it better than I did, longer barrel doesn't mean higher "peak" pressure but it does allow for a longer push.

[SeanD]

You have to have a pretty darn long barrel to actually lose velocity. Lilja recommends a 30" barrel for 300 mag 1000 yard guns, and they dont go over that to decreased accuracy from increased barrel deflection, not because of decreasing velocity.

Personally i think long barreled hunting guns are a pain in the rear. I wouldnt choose a magnum rifle with a muzzle brake or BOSS. Even 26 inches is too long for me sometimes.

[RifleGuy]

Contrary to some of the information provided, a longer barrel does not improve accuracy. When you are shooting the barrel is constantly moving (even on a bench). The length of the barrel determines the time that the bullet remains inside (longer barrel = longer time of influence on projectile) and consequently the amount of motion imparted on the bullet (either horizontally or vertically or both) by virtue of the movement of the barrel after the trigger is pulled. This is in part why bench rest guys add speed locks and high speed springs to their rifles. Reducing the duration of the time that the shooter/action/barrel influence the change of direction of the bullet from original sighting improves accuracy.

A 22" barrel on a 30-06 is about right to match the amount of powder to be burned and the speed of most 30-06 type powders. you would gain about 25 to 45 fps for each additional 1" of barrel length up to about 24" but the trade off is in ease of handling in the brush.

I have a 308 with a 20" barrel, 30-06 and 338 Hawk with 24" barrel and a 30-06 Ackley Improved with a 26" barrel. Each has a slightly different purpose but the 24" length is my preference, on balance, for elk hunting.

[ 11-03-2002, 09:55 AM: Message edited by: RifleGuy ]

[nerta]

:grin: I can't resist getting into this one. Enough barrel length to burn the fuel and long enough to give a good stable hold. Most of my rifles have 22 inch barrels which seem to be the standard for 06, .308, 270 ect from most makers. Keta is right most of his rifles shoot better than he does. Even though he's not to bad a shot :grin: :grin: :grin:

[img]graemlins/berry.gif[/img]

[Chukrchaser]

According to the Remington Ballistics Data web sight, barrel length will change Velocity by 40 ft/ sec per inch of barrel length @ 3500 - 4000 ft/sec based on a 24" barrel. ( another 10 for each 500 ft/sec increment)

So my 25.06 out of a 24" barrel clocks at 3900 -- that means if I used a 20 inch barrel it would clock at 160 ft/sec slower (4" times 40). Not a huge difference but it could be a big deal out towards the maximum ranges.

Not sure I follow the length of sight plane idea on a scoped rifle ?

Chuck,
It doesn't efect a scope.
100 or 200 fps doesn't matter either, unless you are shooting light bullets.

A longer bbl is ok for open country and a shorter bbl for brushey areas.

[Chukrchaser]

:depressed: Oops! the 2 and 3 are mighty close together on this keyboard -- Shoulda been 2900 --

Chuck

Chuck,

Say D'oh!

[SeanD]

How are you getting 3900 fps out of a 25.06? Was that a typo?