24" .223 WYLDE BARREL TWIST RATE INTENDED FOR 77GR. BULLETS

[Jkedsnake]

Hello all,

I tried searching the forums but dd not find anything regarding this...

Does anyone have or has a 24" barrel shooting 77gr bullets in a .223 wylde?

I have a 24" 5.56 that gets decent MOA at 100 yds (smaller than .5).

So just for fun I want to put together a similar set up but going with a .223 wylde chamber, the current 5.56 has a 1:7 twist but available are 1:7, 1:8, and 1:9 to see if I can improve on the 5.56 cambering.

Any advice would be appreciated.

 

[longshot2000]

for the heavier bullets, and the 77 grain is about the heaviest in use, a 1:7 twist is recommended, regardless of the chambering. 1:8 is also used, and I have not seen any difference. A slower twist than 1:8 is not well suited for the heavier round.

I think that was the question.

 

[Onyx Z]

1/7.7 is the optimal twist rate for 77gr SMK's. The BCM KD4 uppers are the most widely available 1/7.7 twist that I'm aware of. I don't believe this barrel is available as a component.

1/7 twist was developed for the extremely long M856 tracer round and seems to have made its way into the commercial market because "mil-spec". Works well for 77gr SMK's and some heavier/longer bullets.

1/8 is close enough to the 1/7.7 to not even matter, so I would consider 1/8 the most widely available optimal twist rate. Works very well for 55-77gr bullets.

1/9 *can* stabilize the 77gr SMK's. I've done it with great accuracy from a 16" chrome-lined barrel.

Typically, the longer the barrel, the less twist you can get away with, but YMMV.

 

[Rocketvapor]

With a 24" barrel your 77 (I assume SMK) will do just fine with 1:7
I put together a 22" 1:7 Wylde for the wife and it's about .5 @ 100.
It's a toss up between the 69TMK and the 77SMK though.

I have a 20" 22 Nosler 1:7.7, a 24 inch 1:8 and a 28" 1:7 and they all handle the 69, 75,77 fine.
I usually load heavier than that longer than mag length. The 28" 1:7 handles them great.
If you plan on shooting longer than 100yds, then the extra stability of the 1:7 over the 1:8 with the long barrel might be a benefit.
If you plan on something like the 80.5 it really needs the 1:7.
My 1:7 does NOT like the 55-62grs though.

 

[Jkedsnake]

Thank you all for taking the time.

 

[Rocketvapor]

Just don't go with the 1:9 for 77's

Barrel quality will mean more than a little difference in twist.
The Wylde or a barrel maker with a custom chamber will usually do better than a real NATO chamber for accuracy.
Pick a good barrel and run with it.

 

[KeyboardKiril]

Typically, the longer the barrel, the less twist you can get away with, but YMMV.

At 100 yards you wont see any stability differences. The more velocity the less twist you can get away with. 1 in 7 is the correct twist for the 77 SMK since that is the bullet used in mk262 5.56 round the military was supposed use with the adoption of the 1 in 7 twist but the problems that occured with the mk262 ammo they ditched the ammo but already had the rifles with the 1 in 7 twist.