[pipsqueak]

I read somewhere on the internet that a .30-06 dosen't have
a different velocity for a 22" or 24" barrel. Magnums supposedly
need more barrel length because there's less air space in the
case which causes the optimum barrel length for bullet velocity
to be longer than the .30-06.

What I'm wondering about is the .308 winchester. What is the
barrel length that maximizes bullet speed? 22"? 50"?

[BattleRifleG3]

Can't give a definite answer there, but the reason magnums have longer barrels is that the bullets need to keep accelerating to reach the magnum speeds, whereas the pressures drop much sooner with other cartridges and the longer barrels don't help.

[lefty o]

air space in the case sounds like it came from a space case. the main reason magnums use a longer barrel, is the case is longer, therefore when a round is chambered it goes deeper into the barrel, therefore you need a longer barrel to get the same useable amount of barrel length for the powder to burn in. there are many more variables involved, but this is the main one that i consider.

[BattleRifleG3]

Case is usually only a half inch or so longer at most, barrels are usually 2-4 inches longer.

Note that the new short magnums don't reach their factory specs out of the barrel lengths most commonly used. Thus they aren't as impressive in real life as on paper, ie the 300 WSM is more in the middle between 300 Win Mag and 30-06.

Another barrel length comparison is that up to 30" barrels, the 300 RUM and 30-378 Wby are about the same. The latter does better in longer barrels, but who would use one?

[lefty o]

most cartridges made in the last 100yrs dont meet factory specs(claims). like i said there are many variables involved in this, powder burn rates, amount of powder, bore diameter, how hot the primer ignites etc, etc.

[auspighunter]

my vanguard is 24 inches
my brothers sako 75 hunter stainless in 308 is 22 inches
i think my dads mod 70 308 is also 22inch but its atleast twice as heavy as the sako
its an awesome gun

[rebel727]

I like 26's but I use hot loads.

[utahvarminter]

22 for hunting is sufficent, 26 for varminting is prefered, twoinches more does more than youd think, and why not 26 and 24?

[BattleRifleG3]

The effect of those two more inches depend on the round used, and even the specific loading. But the tradeoffs of a 20"+ barrel on a 308 aren't worth the extra size if you have to carry it and maneuver it. If you're benchresting it, then by all means use all the barrel you want.

[pipsqueak]

My Speer reloading manual says they actually got better performance
out of a 22" sporter barrel than a 24" pressure barrel when they were
rambling about the anomalies of the .308 Winchester. I'm not really
sure what a pressure barrel is though.