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home sick
December 28, 2010, 09:23 PM
I am looking to buy a 223 Rem. and like to shoot 50 to 55 grain bullets what is the best rifling twist for this weight bullet.

DiscoRacing
December 28, 2010, 09:24 PM
this might help ya out..


http://www.riflebarrels.com/products/caliber_twist_rates.htm

home sick
December 28, 2010, 09:36 PM
Thanks for the web page I have a T/C now and as near as I can tell it is 1 in 12. it handles the 52 HPBT real well but its not to fond of 53 gr HP. I am gona try getting some thing with a handle on the side, either a Rem or Savage.

Bogie
December 28, 2010, 09:42 PM
Depending on the length of the bullet, a 1/12 can work pretty well with 50-52-55 grainers...

I'd consider a custom barrel, preferably Hart or Shilen Select Match - You can buy a new rifle, and hope it shoots, or you can rebarrel an existing action, and it WILL (probably...) shoot...

demigod
December 29, 2010, 09:39 AM
1/12 is optimal. But I've shot some 1/7 barrels that really grouped well with 55 grain ammo too.

Art Eatman
December 29, 2010, 09:47 AM
My Ruger 77 in .223 has a 1:10 twist. Reliably sub-MOA with 50- and 55-grain; same with a blunt-nosed 70-grain.

Bamashooter
December 29, 2010, 07:55 PM
I think a 1:9 twist is best for everything but the heaviest bullets. jmho.

BIG P
December 29, 2010, 08:38 PM
+1 for the 1 in 9 55GR to 69gr heavier not as well.

ndking1126
December 29, 2010, 08:46 PM
My personal experience is 1-9 is too fast for 55 grain bullets. You would want 1-12. Savage (and others) typically put 1-9 on their rifles while Remington is still putting 1-12.

4runnerman
December 29, 2010, 09:14 PM
1 in 9 is ideal for a 55 gn. I think the 1 in 9 is probebly the best for the 55 gn bullet. I think your issue is a remmy(had to get that in) should get a Savage:p

tobnpr
December 29, 2010, 11:03 PM
I think a 12 would be better.
My son's Rem with a 9 twist dislikes bullets under 60 grains, and over 69. It's a pretty damn picky rifle.

My 7 twist Ruger won't even put the lighter bullets on the paper. For all I know, they're blowing up on the way there :)

BusGunner007
December 29, 2010, 11:16 PM
1:14 was the original twist rate, I believe.
It was deemed a virtual 'buzzsaw' upon impact.
Didn't shoot well in sub-zero weather.

Or so I remember from reading too many magazine articles and internet stuff...:o


Twist rates went down as bullet weights went up.
Now everybody wants another caliber...:rolleyes:

I just live with my FMJ 55-gr. civilian stuff.

demigod
December 30, 2010, 09:13 AM
Interesting. None of my 1/9s are that thrilling with 55 gr. They shoot good, but the 1/7s shoot slightly better. I have 4 or 5 1/9s. And they are fine, but they don't do anything particularly well.

My 1/8 White Oak barrel shoots everything really well.

The official military accuracy testing for M193 showed 1/12 to be the optimal twist rate. The data was posted on AR15.com years back, but I didn't save it.

4runnerman
December 30, 2010, 10:37 AM
I don't doubt you at all Demigod,but i have never heard of a 1 in 9 not shooting a 55 gn like a charm. I know 1 in 12 's are good too

thekevster
December 30, 2010, 11:06 AM
Correct me if I am wrong but doesnt the right twist rate have more to do with the bullet's length? I Know the Greenhill formula suggests this.
I am not saying weight does not play any factor but I dont think its the biggest factor.

4runnerman
December 30, 2010, 11:12 AM
(Correct me if I am wrong but doesnt the right twist rate have more to do with the bullet's length?)

Yes it does,but as the weight of bullet goes up,so does the length. 6 of one, half dozen of other.

demigod
December 30, 2010, 12:01 PM
True. But I shoot those Barnes MPG bullest sometimes. They're 55 grain but longer than a 75 grain standard bullet since they're lead free.

4runnerman
December 30, 2010, 12:06 PM
Barnes MPG bullest sometimes

Never heard of them.I went and googled them, Wow those are long bullets Demi. How are they for cost?.

Bamashooter
December 30, 2010, 05:56 PM
the barnes being so long is the reason your 1:8 shoots them better. I shoot from 55-69gr. in my 1:9 mini and shoot them all well. Is it optimal for the 55gr.? prolly not, but i dont have any problems with accuracy.

trg42wraglefragle
December 30, 2010, 08:06 PM
ive only ever shot 40 and 55gr ammo from my 1 in 8 twist Tikka.
have shot plenty of .5moa groups with Hornady and Federal ammo.
Didn't shoot Remington core locks so well, but i don't know if that was the ammo or twist.

I'd go for a 1 in 9 i'd think, seems to be the most versatile

Rimfire5
December 31, 2010, 02:14 PM
My CZ527 has a 1:9 twist and shoots both 55 grain and 65 grain ammos just at an average of 0.435 inches at 100 yards. The best is the 65 grain at 2900 fps with an average of 0.400 even and 55 grain at 2800 fps with an average of 0.42 inches.
It has shot groups of .203, .205, .205, .218 and .250 with five different weights of bullets and under 0.5 inches with 12 different bullet weight/velocity combinations.
The averages are probably degraded some by my techique and my lousy eyesight, but the performance of the CZ is pretty impressive.

It seems to have preferences for bullet shape as much as weight an length but even shoots Fiocchi 77 grain factory ammo at .77 inches.

The 1:9 twist is pretty versitile and does the job if I do my part.

demigod
December 31, 2010, 02:48 PM
Never heard of them.I went and googled them, Wow those are long bullets Demi. How are they for cost?.

They're about $0.28 per bullet. A little pricey, but worth it every so often for shooting steel up close like this....

http://www.youtube.com/watch?v=V4WMw4PikNM

ndking1126
December 31, 2010, 05:35 PM
five different weights of bullets and under 0.5 inches with 12 different bullet weight/velocity combinations

I'm no expert so please correct me if I'm wrong, but I think the key there is the different weight and velocity combinations.

If you hand load, yes, you can shoot different weights because you can adjust the velocity (for example, shoot the 55grains slower so they don't spin too fast, as noted).

However if you shoot commercial ammo, you only get whats there. And when I say the 1-9 is too fast for 55gr (in my experience), that's shooting commercially available ammo without the option to adjust the muzzle velocity.

Bamashooter
December 31, 2010, 07:39 PM
I get my best accuracy with 55gr. bullets loaded to about 3000fps. which is alot slower than factory.

Rimfire5
December 31, 2010, 09:27 PM
You're correct that weight and velocity are pretty well set for factory ammo because most people buy velocity in place of accuracy so manufacturers try to achieve higher velocities within the volume limits of the powder they use and the case capacity while staying a bit on the safe side of pressure.

Factory ammo with 55 gr bullets look like they average around 2850 fps unless your using Hornady SSTs although even their match ammo is rated slightly higher than normal. Hornady uses different powders for their SSTs that they promise to sell after the first of the year but they haven't announced release yet.

I've hand loaded up to 3200 for 55 grain bullets in .223 and still averaged 0.509 with a 1:9 twist, although my rifle shoots slightly better (0.433)between 2750 and 2800 with H4895 behind 55 gr bullets. I've handloaded between 52 grain and 65 grains and all perform well in the 1:9 twist CZ 527.

Factory ammo with 68 to 69 grain bullets look like they run between 2650 and 2735 fps.
Hornady BHTP and TAP in 75 grains run at 2790 but most of the other 75 grain ammos seem to run about 2750.
Most of the 77 grains I've tested seem to run between 2580 for Wilson Combat, 2660 for Fiocchi and up to 2855 for Double Tap. Federal Gold Match in 77 grains runs 2720 fps.

The velocity limit is set by the speed of the powder and the length of the barrel with a hard limit for any particular powder based upon case volume. The slow burning cylindrical powders keep pressure within SAAMI limits and still allow the burn to follow the bullet completely down the barrel to achieve maximum acceleration. A fast burning powder increases the initial pressure but doesn't burn all the while the bullet is proceeding down the barrel and the charge is also limited by the max SAAMI pressure, so the bullet won't be accelerating all the while it is proceeding down the barrel. The critical pressure limit works against faster powders for long barrels.

As for bullet length and shape, the CZ shoots the match boat tail bullets better than the varminter or square based bullets and I would suspect that most .223s would also. When you look at the portion of the longer boat tail bullets and compare them to the shorter square based bullets, the area that touches the rifling is just about the same for equivalent weights. So I don't think it is as much to do with bullet length at equivalent weights. I think it has more to do with stabilization and spin than with overall length. Of course, the increased ballistic coefficient of the match bullets might have something to do with the stabilization and flight and that might be part of the answer for the slightly better accuracy achieved with match bullets.

milo-2
January 1, 2011, 01:29 AM
Hornady did release the name of the powder. It is called Superformance, with some load data in specific calibers.

Rimfire5
January 1, 2011, 08:10 PM
Milo-2

Did you see if you could buy any of it yet?

I would really like to see what it could do.

milo-2
January 1, 2011, 08:50 PM
RImfire,
If you go to Hodgdon's website, they say it will be available mid-January 2011. Limited data though. It looks like it works on overbores.
Good luck.

4runnerman
January 1, 2011, 09:51 PM
Midway has it for sale right now 22.99/lb or 159.99/8 lb container

Rimfire5
January 2, 2011, 07:50 AM
Thanks guys, I had missed the Midway appearance.
Time to try some new powder.

Rimfire5
January 2, 2011, 08:05 AM
Just an update on the bullet weight performance on the CZ 527 in .223.
New Years day, it added yet another good average for a new bullet weight and load. It averaged 0.421 for 63 grain Sierras at 2700 fps muzzle velocity.

The groups shot in the cold included two under 0.3 inches (.223 and .253) and none larger than .65 inches (and that probably was caused by me more than the bullets or the performance of the rifle).

The bullet weight performance from the CZ continues to astound me.
I don't have one other rifle that can shoot so well across a broad range of bullet weights - there's a 25% difference between the 52 grains and the 65 grains bullets and it manages to shoot them both about the same as well as 55s, 60s and 63s. Granted you have to find the right velocity to load for each weight to match the gun's harmonic but the Varmint barrel seems impervious to major issues with harmonics relative to bullet weight.

As a comparison, my .308 shoots 168s and 175s well but that's only 4% weight difference. It doesn't like 150s as much and hates 180s.
My .270 shoots 130s and 140s well and that's 7.6% difference but it doesn't shoot the 130s quite as well as the 140s. It has problems with 150s.
My .22-250 shoots 40 and 52 grains well but doesn't seem to like 45s. Maybe I just haven't found the right combination for the 45s.

Go figure.

Gehrhard
January 2, 2011, 06:59 PM
1:14 to 1:10
Gehr