Difference in Velocities for .308 Barrels

hawkeyesatx

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I own a Ruger American Rifle in .308 Winchester. It has a 22 inch barrel, with a 1-10 twist.

My questions are:

#1 - Does a 1-10 inch twist give higher velocities than a 1-12 inch twist barrel of comparable length?

#2 - What advantages are there of having a 1-10 inch twist barrel for a .308?

#3 - Do any other members on here own the same rifle I do, and what velocities can I expect out of hand loads and factory loads?

I know there are some members on here that sneer, jeer and balk at owning an entry level rifle. I had my own reservations at first when I got the rifle, too. It’s not pretty, it’s not fancy, and it is inexpensive.

The thing that really opened my eyes was when I shot factory Winchester Super X 150 gr bullets at 100 yds, and I shot 8 shots. This rifle put all 8 shots in a 1 inch group. Now, most of the time, I only shoot 3 shot groups to see what kind of accuracy a rifle can manage. This one passed my accuracy requirements with 8 shots, all touching. Yes, the rifle is the ugly duckling, but with the accuracy I get out of it, I’m definitely keeping it.

That’s the reason I’m trying to find out the most about the rifle and I now will be hand loading for it, especially heavier bullets.

Any information about the Ruger American rifle is well appreciated to me.

Hawk
 
1:10 twist will help stabilize longer heavier bullets. Velocity difference between !;10 and 1:12 won't make a difference in a hunting rifle and you likely wouldn't even notice it.

I don't have a Ruger American but know several people that do. They are a good rifle for the money and it sounds like the accuracy is excellent in your rifle. So go hunt stuff and have a good time. Who cares what anyone else thinks. My dad always told me "never make fun of a mans gun or wife"
 
I own a Ruger American Rifle in .308 Winchester. It has a 22 inch barrel, with a 1-10 twist.

My questions are:

#1 - Does a 1-10 inch twist give higher velocities than a 1-12 inch twist barrel of comparable length?

#2 - What advantages are there of having a 1-10 inch twist barrel for a .308?

#3 - Do any other members on here own the same rifle I do, and what velocities can I expect out of hand loads and factory loads?

I know there are some members on here that sneer, jeer and balk at owning an entry level rifle. I had my own reservations at first when I got the rifle, too. It’s not pretty, it’s not fancy, and it is inexpensive.

The thing that really opened my eyes was when I shot factory Winchester Super X 150 gr bullets at 100 yds, and I shot 8 shots. This rifle put all 8 shots in a 1 inch group. Now, most of the time, I only shoot 3 shot groups to see what kind of accuracy a rifle can manage. This one passed my accuracy requirements with 8 shots, all touching. Yes, the rifle is the ugly duckling, but with the accuracy I get out of it, I’m definitely keeping it.

That’s the reason I’m trying to find out the most about the rifle and I now will be hand loading for it, especially heavier bullets.

Any information about the Ruger American rifle is well appreciated to me.

Hawk
That one inch group.....are you using "Imperial" or "Bubba" inches ?:A Stirring:

Anyway, that's pretty good going with entry level gear and much better shooting than I'm capable of. (y)
 
That one inch group.....are you using "Imperial" or "Bubba" inches ?:A Stirring:

Anyway, that's pretty good going with entry level gear and much better shooting than I'm capable of. (y)

LOL I know better than to use “Bubba” measurements.
IMG_2690.jpg

I knew someone would ask, and I have the photo proof. Mind you, this is a 25 yd pistol target I repurposed because I didn’t have any other targets at the moment.
 
Nothing wrong with owning inexpensive rifles. Especially ones that shoot that well. In fact, I just picked up a Ruger American Predator in 6.5 Grendel. First time out, most groups were right around an inch.
As to your question… My current .308 only has a 16.5” barrel with a 1-10” twist. 150gr bullets give about 2650 fps. I previously owned a M70 with a 22”, 1-10” twist that would do around 2800 FPS With 150 gr.
The twist shouldn’t affect velocity much if any. A slower twist will however, limit your choice of bullets. Longer and heavier ones may not stabilize.
 
Sorry I can’t answer all of your questions but I do own two Ruger American rifles, one chambered in 30-06 and one in 243. Both have 22 inch barrels and both shoot under an inch, 3 shot groups with factory ammo. The 30-06 about 3/4 inch groups with the cheap Federal blue box 150 grain lead free copper. I originally got them as ”loaner” rifles for family and friends, hunting wild pigs, deer and pronghorn. Then in addition to being loaner rifles, I kept them for predator control, ranch rifles and kept one in my pickup most of the time.

While they are mass produced, cheap rifles, they shoot just as good as any of my other rifles with the only difference being I wouldn’t cry if one of my Ruger Americans was stolen. They also have an excellent trigger ( 3 lbs) which certainly helps with accuracy. The 243, mounted with a Burris 2-7 scope also accounted for lots of rock chucks, coyotes and several bobcat too. They are an excellent rifle with good value for the money. I can’t remember exactly what I paid, I believe both were $400 or less and the 30-06 came with a factory installed Redfield 3-9 scope.
 
I’ve been a big fan of Ruger rifles for 40 years, I always felt that the M77 scope mounting rings / system was best in class, I hunted hard rugged mountain territory and so many of my buddies had scope base and scope ring issues on their rifles. The 3 position safety on the M77 MK II was again a great secure solution for carrying a loaded rifle through heavy tough brush and cover. The stainless and zytel stocks were excellent for the tough weather. In the Ruger American rifles, Ruger has continued with great features like an adjustable trigger, picatinny scope rail and great accuracy all included in a budget level rifle, that is a lot of value and quality being supplied at the lower end of the market.

I’m just ordering a Ruger American Ranch Gen 2 rifle in .223 / 5.56, it’s going to be a dedicated thermal scope moderated rifle for night hunting . I’ve looked at numerous rifles of up to 3 times the cost but none of them have all of the features that I need, I really like the Tikka T3x lite in stainless or a Bargara 14 but only the Ruger meets the short barrel, threaded barrel, adjustable trigger, lighter weight, picatinny rail fitted criteria, it all comes for under $600. The ability to use standard AR15 mags is another great feature.

In my opinion Ruger has stayed with the times and provides great value products that are well above average.

Enjoy your Ruger American in .308, I have a lot of Blaser for traveling but I still have a big safe full of Ruger rifles that my Blaser’s will never make me sell, most of my Ruger’s have been real work partners.
 
I’ve been a big fan of Ruger rifles for 40 years, I always felt that the M77 scope mounting rings / system was best in class, I hunted hard rugged mountain territory and so many of my buddies had scope base and scope ring issues on their rifles. The 3 position safety on the M77 MK II was again a great secure solution for carrying a loaded rifle through heavy tough brush and cover. The stainless and zytel stocks were excellent for the tough weather. In the Ruger American rifles, Ruger has continued with great features like an adjustable trigger, picatinny scope rail and great accuracy all included in a budget level rifle, that is a lot of value and quality being supplied at the lower end of the market.

I’m just ordering a Ruger American Ranch Gen 2 rifle in .223 / 5.56, it’s going to be a dedicated thermal scope moderated rifle for night hunting . I’ve looked at numerous rifles of up to 3 times the cost but none of them have all of the features that I need, I really like the Tikka T3x lite in stainless or a Bargara 14 but only the Ruger meets the short barrel, threaded barrel, adjustable trigger, lighter weight, picatinny rail fitted criteria, it all comes for under $600. The ability to use standard AR15 mags is another great feature.

In my opinion Ruger has stayed with the times and provides great value products that are well above average.

Enjoy your Ruger American in .308, I have a lot of Blaser for traveling but I still have a big safe full of Ruger rifles that my Blaser’s will never make me sell, most of my Ruger’s have been real work partners.

I have owned 2 M77’s in my lifetime, and they both had beautiful wood. The.25-06 I used to have would group like the American rifle. But it was at least 2 or 3 pounds heavier, and after a long day of hunting, I was feeling that heft. Plus, I never wanted to scratch or ding the stock on the M77’s either.
With the American, it will definitely see its fair share of use, and I will not worry about scratching or dinging the stock.
I am just so pleased with the level of accuracy it can provide. I never knew they could do that. I know everyone has said that the .308 is an inherently accurate cartridge, but teaming it with a rifle that is accurate as much as the cartridge, it just can’t be beat.
This rifle, hands down, has out shot rifles that I have owned that were 3 to 4 times more expensive than this one.


Hawk
 
Forgive my ignorance about what I am to ask.
Has anyone done any experimenting with factory ammo and the true velocities they get compared to real life velocities? Are there any brands or brand of ammo makers that live up to their published velocities?
What about hand loading? Can I expect to get close to published velocities of the .308?
Is there a one bullet weight solution that can work for a myriad of big game?
I’m thinking that the 1 in 10 inch twist will favor middle to heavy weight bullets. Am I right or wrong?

Hawk
 
Forgive my ignorance about what I am to ask.
Has anyone done any experimenting with factory ammo and the true velocities they get compared to real life velocities? Are there any brands or brand of ammo makers that live up to their published velocities?
What about hand loading? Can I expect to get close to published velocities of the .308?
Is there a one bullet weight solution that can work for a myriad of big game?
I’m thinking that the 1 in 10 inch twist will favor middle to heavy weight bullets. Am I right or wrong?

Hawk
If you want the optimum twist rate for a specific bullet here is the basic math...

Bullet dia squared X(times) 150. Then divided by bullet length =(equals) twist in inches.....
 
Forgive my ignorance about what I am to ask.
Has anyone done any experimenting with factory ammo and the true velocities they get compared to real life velocities? Are there any brands or brand of ammo makers that live up to their published velocities?
What about hand loading? Can I expect to get close to published velocities of the .308?
Is there a one bullet weight solution that can work for a myriad of big game?
I’m thinking that the 1 in 10 inch twist will favor middle to heavy weight bullets. Am I right or wrong?

Hawk
Factory bullet velocities are typically tested with longer than normal barrels for a .308win. Most manufacturers test with a 24' barrel since that's what SAAMI specifies. Shorter barrels mean slower velocities. Each barrel even consecutive serial numbered guns, will be slightly different and the only real way to figure it out is to chrono the velocities out of your gun. Shooting the same box out of my Savage, Winchester, or Remington .308's will produce completely different velocities.

That said, I'd expect your rifle to shoot between 50-200fps slower than the box with your barrel being 2 inches shorter than the test barrel likely was.
 
Technically a faster twist should slow your velocity, how much, who knows but it wont be by much.

barrels are a law unto themselves. I have shot the same .270 load through 2 different rifles, same twist rate and one was 140 fps slower than the other. Same barrel length, also did it with 2 308's but that was a hard call as one was a 20" barrel the other a 22" barrel.

Has anyone done any experimenting with factory ammo and the true velocities they get compared to real life velocities? Are there any brands or brand of ammo makers that live up to their published velocities?
What about hand loading? Can I expect to get close to published velocities of the .308?
Is there a one bullet weight solution that can work for a myriad of big game?
I’m thinking that the 1 in 10 inch twist will favor middle to heavy weight bullets. Am I right or wrong?

Hawk

Hawk I have tested some Factory ammo against their claims. So far, from memory none have matched the claims. Most were 90 to 150fps slower. I have had them upto 200fps slower and a couple have been with in 50fps of the claim.

I have found some PPU to be closest the mark. I am told most of the factory's test their ammo in a 26" barrel so this could account for the discrepancy.

1713931045001.png
 
Last edited by a moderator:
#1 - Does a 1-10 inch twist give higher velocities than a 1-12 inch twist barrel of comparable length?

#2 - What advantages are there of having a 1-10 inch twist barrel for a .308?
1. No. Quite the opposite. Reducing speeds. But reduction of velocity is negligible. Forget about it.
2. Heavier bullets. If you are reloader, try 200 grains, or more.
 
I’ve shot more .308 than anything else over the last 40 years. Lots of different rifles, different barrel lengths, different twist rates. As far as hunting goes, I’ve tended towards monolithic copper bullets in Barnes or Federal loaded ammo; 150 grain for .308, 165 grain for .30-06 and 180 grain for 300WM. The choice of caliber depends on what I’m hunting at what range. These choices have worked quite predictably for me. Having said that, the 10 twist will allow you the shoot this rifle with heavier bullets should you see the need.
 
I’ve got 3x 308’s that have 16” barrels… an AR10, REM 600, and a kimber Adirondack…

Shooting the exact same load (Barnes ttsx 168gr over 43.5gn of IMR 4064), from the same lot of powder, etc… they all have different velocities..but they are all +/- 30 fps of each other….

As a rule they are all between 125-150 fps slower than the advertised speed of Barnes vortx 168gr factory ammo… (iirc Barnes claims 2750 on that load?)
 

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