7 twist on a 26" .223
- Thread starter Fingi
- Start date
It would help everyone in making a suggestion if you state the purpose of and bullet(s) that are going to be used
CJ6
Silver $$ Contributor
What bullet/bullets do you plan on using ? What's it being used for (target or hunting)? Get it twisted for the bullet/ bullets (weights) you plan on using and get it throated accordingly. .Skip the ball ammo and find someone to help you get started in loading your own the rewards will be worth it.
Last edited:
CJ6
Silver $$ Contributor
9 twist will work with them
If it was me building this rifle for the same purpose I would plan on using 80 grain bullets for those distances and use a 7 twist to open up the option of trying some 90 grainers.
Before anyone gets excited about me recomending 90 grainers (and the freebore needed for them) in a rifle intended for 69gr smk's. it has been discussed here before(by people with experience) that a rifle throated for 90's works just as good as it ever could with the 69 - 80's. There are a few shooters here who do just that and even the light 55 grain bullets (long jump with the 55's). And I especially wouldn't hesitate on the long throat using ball ammo at 100-200 yards.
Don't forget there is a case capacity advantage with the longer throat over a shorter one(say .077 vs .169).
But if your heart is set on 69er's and less go with an 8 twist, 7 will be just fine too.
Before anyone gets excited about me recomending 90 grainers (and the freebore needed for them) in a rifle intended for 69gr smk's. it has been discussed here before(by people with experience) that a rifle throated for 90's works just as good as it ever could with the 69 - 80's. There are a few shooters here who do just that and even the light 55 grain bullets (long jump with the 55's). And I especially wouldn't hesitate on the long throat using ball ammo at 100-200 yards.
Don't forget there is a case capacity advantage with the longer throat over a shorter one(say .077 vs .169).
But if your heart is set on 69er's and less go with an 8 twist, 7 will be just fine too.
CJ6
Silver $$ Contributor
There are other barrel makers OR wait till the twist you want is available. Any of the twists mentioned would work BUT are faster than what you need for the bullet weights listed. If you have the rifle throated for the 69 SMKs using heavy (more twist suited weight bullets for the 7-7.7-8 twists) will have them pushed so far in the case to be wasted efforts.
Ooooo you recommended 90 grainers!
IME 77gr will go 600+, but you'd be giving up a bunch to a good 80/(90shhhh) load.
Under 600, the 77/69 will do just fine, and the 55gr does fine from a 1:7
Do you want to shoot 5.56 ball ammo?/ if so, dont get the 223 chamber, a wylde or other with longer throat.
-Mac
And Under 600 the 80's will do even better
90's, I don't even know why someone would want to deal with the finicky little buggers. To much bullet for such a little case
I am not sure which twist to tell you to get, but I think that 7, 7.7 and 8 are faster than you need for bullets up to the old Sierra 69 MK.
I have shot many thousands of the 69s to 300 and many thousands of the Hornady 75 BTHP out to 600 yards with no problem using a 9 twist. I am not not sure that the longer 75 A-Max would work, but I would probably try it out.
Danny
Before you decide, ask yourself how serious you are when it comes to hitting targets at 600 yards. My Howa-1500 "fun gun" with a 1:9 twist shoots SMK 69gr bullets great, always sub 1/2 MOA at 100 yards and frequently sub 1/4 MOA. It will also lob those 69gr bullets down range 600 yards for fun. You can ring a steel target much of the time, but not always if the wind is blowing. If that satisfies you, 1:8 will be fine.
But I recently got interested in F/TR competition. It's often done on a local level in a low-key atmosphere and you don't need real fancy equipment to compete and even win. If you haven't tried F/TR, think about it. It's very entertaining and you will learn a lot about marksmanship. However, 69gr bullets are at a significant disadvantage at 600 yards. You're likely going to use Berger VLD 80gr bullets or something quite similar. For that you're probably going to want a 1:7 twist barrel.
Of course, a gun set up for 80gr VLDs will still shoot 55 grain bullets, but it won't be optimum.
What exactly are you referring as not optimum? Can you elaborate please?
Since the bullet diameter is fixed by the caliber of the gun, heavier bullets suitable for long range competition are longer than lighter bullets of similar shape. Therefore the chamber optimized for a cartridge loaded with a long bullet will likely have a throat which is longer than desired for shooting shorter (lighter) bullets. They'll shoot, but it might be impossible to achieve best accuracy (precision actually) with a cartridge shorter than optimum for a particular chamber.
Said another way, if you chamber a rifle for shooting long (heavy) bullets, the shorter (lighter) bullets shot from the same chamber will likely have a "jump" longer than you might desire.
Good reply,
Twist is dependent on stability in flight, where too much tends to either blow up a bullet (not common in 223), or reduce velocity a bit. I know of several BR shooters who are less concerned with BC as velocity (of matching the two at highest node possible).
Jump on the other hand is twist independent and instead chamber dependent. Thankfully this has been resolved, the 5.56 chamber is far longer than the standard 223 chamber; thus the question is: light bullets, or 5.56 ball loads? I believe the OP responded "... 55gr ball ammo for close...". This would be critical, as you don't want to and should not shoot 5.56 from a standard 223 SAAMI chamber.
Yes the 1:7 is well stabilized, but I don't think it'll be blowing up the 55s, and the 52/53 MK will produce excellent results given good quality everything else. You are correct, 1:7 isn't needed for the 52/52;55gr.
I see new info; if the OP isnt handloading yet, this discussion is of limited value; I don't see factory loads over 77gr, should some be available, 80gr would be it. Back to the " poorly
" suggested 90gr, that is an additional case of throating even further and all jump concerns are valid doubly so.I still recommend a 1:7 as this OP has an implied perceived desire to shoot long range and the 90 will tickle anyone's fancy to try it; combined with 55gr ball suggestion; I perceive a future trial of 62gr surplus for which the 1:7 is needed.
There enough said, there isn't a right or wrong, just opinion; and now toss mine onto the pile.
OP, best of luck, and there isn't a wrong answer in this case unless your needs constrict or shift along this decision process. 223 is a hard one just because of all the options
-Mac
Similar threads
Upgrades & Donations
This Forum's expenses are primarily paid by member contributions. You can upgrade your Forum membership in seconds. Gold and Silver members get unlimited FREE classifieds for one year. Gold members can upload custom avatars.
Click Upgrade Membership Button ABOVE to get Gold or Silver Status.
You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.
To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.
Click Upgrade Membership Button ABOVE to get Gold or Silver Status.
You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.
To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.