Can I ask our firearms experts a question

[Silent Earth]

I know how to shoot along with the best BUT I admit not to understanding much about balistics, tragectories, power, muzzle energy etc Soooooo

If say as an example a Ruger 10/22 has an optimal barrel length of 11 1/2 inches then have longer barrel lengths? I get shorter for concealment or use in confined spaces but if a barrels optimum performance is achieved at length A then why go longer??

 

[Brent S]

I know how to shoot along with the best BUT I admit not to understanding much about balistics, tragectories, power, muzzle energy etc Soooooo

If say as an example a Ruger 10/22 has an optimal barrel length of 11 1/2 inches then have longer barrel lengths? I get shorter for concealment or use in confined spaces but if a barrels optimum performance is achieved at length A then why go longer??

Hopefully the manufacturer has allready figured out the optimal ballistics for their weapon. If you were to go longer with a 22 than you needed for accuracy then it would be heavier and cost more to manufacture. I am sure some thought and R&D goes into that by the makers. Of course there can be custom tweaks here and there for individuals to make it better for them, but overall most major designs were allready worked out for the specific weapon. Early firearms were experimental in design. The ones that worked well were replicated.

 

[Silent Earth]

Hopefully the manufacturer has allready figured out the optimal ballistics for their weapon. If you were to go longer with a 22 than you needed for accuracy then it would be heavier and cost more to manufacture. I am sure some thought and R&D goes into that by the makers. Of course there can be custom tweaks here and there for individuals to make it better for them, but overall most major designs were allready worked out for the specific weapon. Early firearms were experimental in design. The ones that worked well were replicated.

I'm wondering if 15 and 16 inch barrels on stuff like 10/22s and AR15s is more to do with gun laws than gun physics? Y'know if the optimum barrel length was say 11.5 inches it would make the guns very compact and theirfore concealable thus causing the authorities problems?

This is an enlightening thread on The Highroad
https://www.thehighroad.org/index.php?threads/ideal-barrel-length-for-a-22lr.872/

it appears ( so far) that 14 inch is optimal in 22LR SO FAR

 

[Silent Earth]

What I'm reading is this

"To sum up some of what has been said;
Velocity; In a .22LR there is a point where the maximum velocity is achieved. After that point the friction between the barrel and the bullet actually decreases velocity. Appearently the max velocity occurs at 14". In a rifle, a barrel this short requrires a federal tax stamp, so the best comprimise would be a 16" barrel. This would give you the most velocity for a non-NFA weapon.
Accuracy: The reason that a longer barrel is more "accurate" than a shorter barrel is simply because the sights are further apart which decreases the human error in sighting. Obviously this is only a factor with iron sights and only is a factor if the rifle utilizes the additional length. A rear sight mounted at the rear of the action is better than a rear sight mounted half way down the barrel as far as accuracy is concerned. With a scope, barrel length isn't a factor.
Spin: The amount of "spin" required is enough to stablize the bullet. This is determined by the length of the bullet. A given rifling twist will stablize a range of bullet lenths, deviate from that and you won't stablize the bullet. Once the bullet is stabilized, allowing it to "spin" in the barrel provides no benefit. "

I would like my fellow preppers to comment as i rely on youre council for much

 

[Silent Earth]

Another thread makes me realise the answer is not going to be as simple as I thought

http://www.varminter.com/forums/topic/12917-optimum-barrel-length-for-ruger-1022/

 

[TexasFreedom]

It is easier to pick the 'ideal vehicle'. For what? Cargo? Noise sensitive? Weight? Efficiency?

How much powder in the load? How heavy is the bullet? What twist ratio? How much heat can the barrel absorb/dissipate (warpage)? Faster or slower burning powder?

So many variables. What assumptions you use changes the answer.

 

[DrHenley]

The 16" minimum is because of Federal Law. Any rifle with a barrel less than 16" has to be registered as a SBR (Short Barreled Rifle).

There are a number of factors going into optimum barrel length. For me, there are two reasons I like longer barrels (most my rifles have barrels 26" or longer)
1 A longer barrel is quieter with less muzzle blast. Once you surpass that so-called "optimum length" the pressure starts dropping. A 29" inch barrel on a .22 using subsonic ammo doesn't even need a suppressor. I had a 29" barrel on my squirrel rifle, but it was too cumbersome to use squirrel hunting so I had it cut down to 25".
2 It is easier to hold still because of the long moment of inertia. This is one of two reasons why you see match rifles with muzzle weights. However, if the weight is too much, then it can cause muscle fatigue which leads to shaking.

A long thin barrel has a lot of whip, which means loads have to be carefully developed to be in the "sweet spot". Rifles with long thin barrels tend to not shoot very well with factory ammo. The second reason for muzzle weights is that they dampen the whip of the barrel. A short fat barrel has a much larger "sweet spot" and is more forgiving with different loads, therefore usually works better with factory ammo.

Of course with rimfire ammo, you are limited to factory ammo, so it's a matter of trying a lot of different brands until you find one that has the right harmonics.

 

[Daniel8]

For ar15/5.56 rifle I see no need to go smaller than 16". You loose to much velocity from the round making it drop faster. If trying to hit a target at 200 yards you will want 16" barrel. I had a 10" barrel ar15 and wouldn't shoot it cause the muzzle blast was so intense that my gums hurt from shooting it.
For the .300 black out round you don't gain any velocity past 9" so if you wanted a short barrel "truck gun" that would be my choice. But then again don't expect much out of it in terms of distance. .300 black is one of the best choices for CQC type shooting as it packs a punch, allows for a compact platform with 30 round mags.
I prefer my .308 semi rifles (AR10 & Scar17) over anything else. Though they are heavier I can use them just fine in close quarters and can reach out to 600 yards. I have a close quarter shooting range I set up in the woods here and I litterally punch through 24" pines with the 7.26x51nato rounds. As the old saying goes the .308 turns cover into concealment!