RugerM77.270

I'm looking at getting a .308 and start to shoot at extended range out to about 600 yards. I've noticed that some people want to use a short barrel say 20 or 22 inches them some are 26 inches. I would think that the longer barrel would be better but if it is how much better and why? I know you gain 15-20 feet for every inch but what does that add up to in ballistics?

My plan is to get a Remington SPS Tactical 20'' barrel or Varmint 26'' barrel to learn the basics and also buy some reloading equipment before I move into the big custom rifles.

SwampCollie

You gain 15-20 feet per second up to a point.

Every cartridge has its magic barrel length. I have no idea what it is for a .308, but I suspect its somewhere in the 20-22" region. A .22 LR for example, has a magic barrel length of 16". What does this mean? At that point, all your powder is burned and your bullet is going as fast as it will go. Much anything past that point is just extra and could even theoretically slow you down.

There are more variables with a .308, especially if you are a handloader, because you can load faster or slower burning powder. So the magic barrel length number will change a bit. To be honest, I think there are many more important considerations that lead up to accuracy than barrel length..... most of them have to do with having a squared action that is properly beaded and a properly headspaced bolt and chamber.

That makes if fairly easy. All you have to fool with is reloading, which is fun, education and addictive.



Here are my thoughts on barrel length... just for what its worth...

When you fire a rifle, your barrel oscilates, just like the amplitude on radio waves, or a limber 10 foot length of 1/2" PVC pipe. The key to being accurate is having your bullet leave on exactly the same amp frequency or wave each time. Hopefully this is making sense to you. As your barrel heats up, its oscillation is more extreme, the waves/whipping gets larger... thats why hot barrels frequently throw shots high or low, but not side to side.

Now, take my PVC example.... say you have a 1/2" PVC pipe 10' long. You can hold it in the middle and shake it, and it will flex and bend like a 4 weight fly rod. In turn, take a 6" section of it, and would take a hydrolic press to flex it. In my opinion/experience, the same principal applies to rifle barrels. The shorter the barrel, the less the flex, the easier it is to have the bullet leave on the same wave/whip every time. There is a law of deminishing returns, however, because your ability to shoot the gun well with a short sight radius drops drastically (it is much less forgiving, which is why its hard to be accurate at longer ranges with even longer barreled handguns as opposed to rifles, as tiny form flaws are exponentially magnified downrange). This is also why bull/heavy barrels tend to shoot more accurately than their tapered counterparts, because they are stiffer and flex less while firing.

Also, as you pointed out, you start losing velocity, and if all your powder isn't being burned up, you could not be getting the exact same amount of pressure/velocity each time. Moreover, of course, a shoulder fired "rifle" cannot by federal law have less than a 16" barrel... so there is that consideration too.

This makes sense to me. Could it be totally way the heck off... sure I guess so, but thats how it was explained to me when I was a bit younger, and its been my experience that it holds true for the most part. Most of the really knockout rifles I have, use barrels under 24" in length. This is also part of the reason (I believe) that a lot of folks are not pleased with the accuracy out of their TC Pro Hunters.... because they all come with those long 28" barrels that really aren't all that heavy.

Sorry to ramble on... hope I was able to shed some light.

Wilds

Short barrels don't shoot...

Neither do skinny ones.........grins.

Paul L Mohr

A longer barrel may give you more velocity, up to a point but it won't always be more accurate. A shorter barrel is more stiff. Most target guns have shorter barrels on them, velocity can be compensated for, accuracy loss cannot be.

Paul

oldelkhunter

Your not losing much if anything with a 20" over a 22 or 24 especially with a 308.

nchawkeye

Agreed...My brother has had a Model 7 since the mid-80s, and it's plenty flat shooting out to 300 yards for deer hunting...Now, I don't care for the short 20 inch barrel on it, just seems too short for my taste...When I rebarreled my .243 I went from a 22 inch to a 24 inch barrel, just seems to fit me better...

I'd base your decision on which feels best to you...Go shoulder a .308 or a 7mm-08 in a Remington CDL, they come with 24 inch barrels, then compare to a regular 700, or a M-77, they have 22 inch barrels...

Now, when you put a 24 inch barrel on a long action, it just seems a little long, for me...

One other point...With short action guns, the added length reduces barrel jump a bit...The gun seems to recoil straight back instead of jumping...Have fun...

cjwink

I have a 7mm08 with a 16.5 inch barrell that will shoot with the best of them.. I also have a 243 Model 7 with a 20" barrell and a 22-250 with a 22" barrell and a 308 with a 24" barrel.. They all shoot about the same..

gunnermhr

I guess you haven't been to to many competitive matches

"Neither do skinny ones.........grins."

You've been misled. Although you wont see any skinny barrels at competitions I believe it is due to heat more than anything else. I have a custom 300 RUM improved with a #5 Contour 30" Hart barrel that will out shoot just about any heavy shortfactory barrel. It's only good for 4 shots then needs to cool down. But it sure is accurate.

If I were in your shoes and wanting to get that 308 there would be no question as to weather I was getting the 20" or 26" tube. Hands down longer is better. It's very easy to take it to a gunsmith and have a couple inches cut off if you think it's too long and effecting accuracy. You absolutly cannot add length to it no matter how good your gunsmith is.

Also you canot compare the accuracy of a TC Pro Hunter to a good Bolt action. The barrel lenght is not the major deminishing accuracy factor in that situation.

SwampCollie

Sure you can. Accuracy is accuracy, whether its from a pellet gun or your anti-satelite 300 RUMAI.

I do agree that barrel length may not be THE determining factor, but even comparing TCs with TCs it seems to be the case (unless SW has changed a bunch of stuff and they jsut don't hit on nothing anymore.) Also, as you illuded to, an Encore maybe inaccurate and the way that you need to correct that.... there is where you cannot compare an Encore and a bolt action. Most of that has to do with excessive head space/inconsitant lock up on Encores. But I do know that I have a regular old Encore with a 24" barrel that couldn't hit the ground if I was aiming straight down. TC still ain't sent her back yet either. I don't know what their issues are, but I've read and heard a whole lot of unhappy comments about them as of late.

Paul L Mohr

My step dad used to compete at the state level in benchrest and I competed as a young teen on the regional level in both centerfire and rimfire benchrest. I have been to one or two competitions.

I have seen pistols with 12 and 14 inch barrels pull off some amazing groups with a centerfire action.

Some of the rail guns have extremely short barrels as well and are VERY accurate.

Paul