Is a 20" barreled 30-06 that bad?

[Andy]

Lower muzzle velocity equals less recoil.

Negligible and more than offset by the weight loss with the shorter barrel. Each inch of barrel length increases or decreases MV by about 1%.

 

[rifleman762]

Negligible and more than offset by the weight loss with the shorter barrel. Each inch of barrel length increases or decreases MV by about 1%.

A replacement short barrel might be a heavier profile, though. Cut down, you are absolutely correct. The escaping gas also has a higher velocity. I could do a test with my 20" and 14" 308 barrels . But I don't have a consistent way to directly measure recoil force. In total, the recoil difference is negligible between a 24 and 20 inch barrel.

 

[bunny]

I was shooting my Ruger ultralight today with its 20” no issues, and It groups 220 RN’s sub moa.

 

[Ardent]

With ear plugs they all sound the same.

 

[hoytcanon]

Negligible and more than offset by the weight loss with the shorter barrel. Each inch of barrel length increases or decreases MV by about 1%.

So with no barrel I should get around 80%?

 

[legi0n]

So with no barrel I should get around 80%?

indeed but then it would be kindof prohibited.

 

[hoytcanon]

indeed but then it would be kindof prohibited.

How can "nothing" be prohibited?

I believe we have found a loophole...

 

[legi0n]

How can "nothing" be prohibited?

I believe we have found a loophole...

he same way the action is the firearm

 

[medvedqc]

Who's making all these 20" 30-06 rifles? I can think of the now discontinued m77 "Ruger Ultra Light"

zastava full stock.

 

[Ardent]

he same way the action is the firearm

What exactly is the sound of something going over one’s head?

 

[hoytcanon]

What exactly is the sound of something going over one’s head?

Kinda like the old joke;

"What's the difference between a duck?"

Answer;

"One foot is both the same."

 

[bearkilr]

Negligible and more than offset by the weight loss with the shorter barrel. Each inch of barrel length increases or decreases MV by about 1%.

So if I cut my 257 Wby bbl down from 26" to 6" I only lose 20% MV? Cool.

 

[yomomma]

So if I cut my 257 Wby bbl down from 26" to 6" I only lose 20% MV? Cool.

Assuming same ammo/ powder. You could always reload with a faster powder

 

[BCBRAD]

My 30-06 load in a 570mm bbl (22.4") runs a 200gn Accubond at 2700 ft/s, muzzle pressure is 8229 psi.

A 508mm bbl (20") runs the same bullet /load at 2544 ft/s, muzzle pressure 11,374 psi.

That is ~38% increase in muzzle pressure for the shorter bbl.

An increase in 3 db, from 162db to 165 db in the sample above would equate to ~1.23 times the perceived sound of the short bbl over the longer one.

 

[AlexF]

Good comparison: expect 24” 270 Win blast and pressure from a 20” 30-06.
Not that bad at all since nobody is scared of a 24” 270 Win.

30-06 like 7mm Mauser, 308 Win and 223 Rem are all military cartridges.
They are designed to be accurate, trouble free, very flexible with good barrel life.
With the right ammo both 308 and 223 work perfectly at medium range with a 14” barrel.

Alex

 

[rifleman762]

So if I cut my 257 Wby bbl down from 26" to 6" I only lose 20% MV? Cool.

It really depends on the case capacity to bore volume ratio. If you have an "overbore" cartridge like a 257 Weatherby you will lose more velocity than an "underbore" cartridge like a 308 Win. Think of it this way: the muzzle blast is wasted energy not used to accelerate the bullet. The more muzzle blast (higher gas pressure at the muzzle) the more velocity you will lose with a shorter barrel. Most small bore magnum cartridges have 12k to 14k psi pressure at the muzzle with a 24 to 26" barrel. A 308 with a 14" barrel has 14k psi pressure.

 

[todbartell]

So if I cut my 257 Wby bbl down from 26" to 6" I only lose 20% MV? Cool.

26" 3400 fps, 6" would be 1650 fps (using RL25) - according to Quickload

 

[mb9]

I would try 20" first. I have a shorter 760 Carbine and would prefer the longer 20" bbl instead. They still handle very well.

Thanks for advice. You are right, I can always cut it shorter later if need be...start at 20" and try it out.

 

[bearkilr]

It really depends on the case capacity to bore volume ratio. If you have an "overbore" cartridge like a 257 Weatherby you will lose more velocity than an "underbore" cartridge like a 308 Win. Think of it this way: the muzzle blast is wasted energy not used to accelerate the bullet. The more muzzle blast (higher gas pressure at the muzzle) the more velocity you will lose with a shorter barrel. Most small bore magnum cartridges have 12k to 14k psi pressure at the muzzle with a 24 to 26" barrel. A 308 with a 14" barrel has 14k psi pressure.

I know how it works. I was pointing out that this "standard" isn't a basis for all calibers.

 

[Ardent]

Thanks for advice. You are right, I can always cut it shorter later if need be...start at 20" and try it out.

Can only cut it another inch and a half, which is pretty meaningless in handling and ballistics. Cut it to 20, and go hunting.