.223 1:9" twist

[Peakbagger46]

What bullet weights is this twist best with?

 

[DoubleTapDrew]

45-69gr. Sometimes the heavier rounds like 68-69gr will start keyholing in 1:9 barrels but you just need to buy a box and see if it works in your rifle.
If you are mostly interested in mil spec stuff like m193 (55gr) or M855 (62 gr) both will be fine.

 

[jimmyraythomason]

I get excellent performance from Prvi Partisan 75 grain Match ammo in my 1:9 twist Stevens Model 200. Wolf 62 grn sp ammo is poor with 4" groups at best. It also groups 55 grain Hornady very well.

 

[joed]

I had a Savage 10fp in .223 with a 1:9 twist. It was extremely accurate with 69 gr bullets at 100 yards.

My load was pretty much max from the Lyman 48th edition and shot fine. However, if you're going to shoot it at lower velocities I couldn't tell you how well it shoots. But it was fine in my rifle at my velocity which the book listed at 2900 fps.

 

[mc223]

60g V-Max has always been a consistant performer from my 1 in 9 barrels.

 

[joed]

I also found that anything under 55 gr did not shoot well in my Savage as Jeff56 mentioned. I tried 40 gr bullets once and was really disappointed. Even 50 gr was questionable.

 

[Steve in PA]

I've shot everything from light 40gr bullets on up to 75gr BTHP out of my Savage 12FV. All outstanding groups!!!!

 

[WardenWolf]

Barrel length matters, because a longer barrel means a faster moving bullet, which also translates to faster rotation. So a 20" barreled 1:9" gun is going to be able to shoot heavier bullets than a 16" 1:9" gun. My 20" Saiga .223 with a 1:9" barrel ate 68-grain bullets just fine and those are what I hunted with. I sighted in my scope at 100 yards, so I'd know if it were inaccurate or keyholing.

 

[1stmarine]

Hi,
It is not just the bullet grain but the bullet construction and lenght.
Also the length of your barrel is a factor.

For example if you use a barnes TSX 70gr the manufacturer recommends a 1:8 twist of rate and the reason is because since they are solid copper the bullet is longer. If this bullet had a lead core FMJ it would be ok in 1:9.
So follow manufacturer directions and also other folks experiences with good loads like the vmax 60grain above is hard to beat.
You might find the Sierra Matchking HPBT 69grain to be very good too. I have great results with this one with a 20" match barrel.

http://www.sierrabullets.com/index.cfm?section=bullets&page=bc&stock_num=1380&bullettype=0

Cheers.
E.

 

[sappyg]

I'm not completely sold on barrel length and bullet weight as a deciding factor.

IIRC i had a 20" HBar in 1/9 twist that really did wonders with 52g Match Hornady's. I admit that I never tried heavier bullets. It never crossed my mind. using the 'longer barrel faster theory' this bullet should have faltered but IME that was not the case.

it's probably rifle specific but were I to choose the optimum weight for the 1/9twist you can't go wrong between 55 anf 65 grains. I saw 75g bullets keyhole on the range just last week in a 1/9 barrel. 70's were still ok in that rifle. Bullet length had more to do with the results than bullet weight or barrel length.

 

[Jim Watson]

I have a 9 twist .223 that is more accurate with a 52 gr SMK than anything heavier/longer.

The dirty little secret is that you have to shoot the gun, the whole collection of Internet Experts cannot predict what YOUR rifle will do except in the broadest of terms.

 

[52grain]

I shot 10 rounds of 69 grain sierra Matchking out of a 1:12 twist without key holing. Wasn't the most accurate round of shooting that I have ever had, but it wasn't bad either. It was a 26" barrel, but the barrel length is a much smaller portion of the equation than the rate of twist.

 

[1stmarine]

I'm not completely sold on barrel length and bullet weight as a deciding factor.

This is covered extensively in many level1 sniper training theory courses. Also there are many good books about this subject.

For example these are high quality barrels made for match grade accuracy....

http://www.kriegerbarrels.com/DCM__AR_15-c1246-wp3394.htm

You will see the recommendations of not less than 1:7 for a 16" barrel (Currently the M4 standard GI twist of rate) and then either 1:7 or 1:8 in barrels from 18"to 20" for the higher grain bullets. 1:8 in 20" is good up to 77gr in most top end bullets although I get better results with the Hornady 75gr BTHP match. but the 77gr is perfectly stabilized. it is just a matter of my match rifle liking better the hornady 75gr better than the berger 77gr for example. Both loads are around and below 0.4 MOA which is very good for a national match rifle.

All boils down to internal ballistics and the characteristics of the specific bullet(grain, construction, length, speed), barrel twist, nr. of grooves, material, lenght, etc... Also you need to reload and work your quality loads up slowly with different combination until you find what your rifle 'likes'.

So this is why you have to follow manufactures and loading information as well as trying the rounds with your own system. Folks can give you direction and good advice but in the end you have to try, try, try.

Internal ballistics is also a complex world just like external ballistics.
1:9 is plenty for most people but if you want to try heavier match bullets you need to go to 1:8 in a 18" or 20" inches or even more.
In the AR you are maxed out at 77gr with the Bergers and SMKs due to COAL but you can try 80gr and even 90gr and 1:7 and 1:6.5 twists if you single feed them.

Some folks are modifying magazines to seat the 80gr bullets (Camega is a good one for this) but I don't get any better results than the 77gr or 75gr, again, IN MY CARBINE. Somone else's might be a different story.

Cheers,
E.

 

[jimmyraythomason]

The dirty little secret is that you have to shoot the gun, the whole collection of Internet Experts cannot predict what YOUR rifle will do except in the broadest of terms.

There it is. You will never know how the pudding taste until you eat some yourself.

 

[Peakbagger46]

Interesting that barrel length may effect things. Sounds like the general opinion is that I will have to build and test a bunch of different rounds to figure out what works best... Gee, darn, I sure hate playing with loads Guess I know what I will be doing when I go back to night shift in a couple of months. May even have to set up my flashlight to do some night shooting...

 

[Jaybird78]

My Savage 12 26" barrel likes 60 grn v-max and 68 or 69 grn match from hornady and nosler. With 55 bulk FMJ it was just so-so. I handload and anything lower than 55 was like shotgun patterns. I haven't tried in the 70-77 because I just don't have a need to.

My Armalite Ar 20" barrel usually is just fed 55 grn bulk for plinking but I have started using the 60 grn v-max for some upcoming varmint shooting(I hope).

Handloading gives you the ability to fine tune for your rifle and like others have posted every rifle is just different. Good luck.

 

[jpwilly]

The answer is some do and some don't...you'll have to shoot yours to find out.

I have a 1-9" 20" Bull Barrel DPMS 223 rem rig that won't shoot the 68 or 69 grain Black Hills Match loads they do keyhole. But it shoots 50gr - 62gr very well.