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baldtop
12-27-2006, 11:31 PM
Wiil a .223 barrel with 1 in 8 twist stabilize 80 grain bullets? What about 45 grain bullets?

recoil junky
12-28-2006, 12:31 AM
The faster the twist , the heavier (and longer) the bullet the barrel will stabilize, the slower the twist the lighter (and shorter) the bullet. My .223 has a 1 in 14 twist and really likes bullets 55 grains and under. It started life as a .222 so that's where the slow twist comes from. Most .223's are 1 in 12 or 1 in 10 depending on manufacturer. If you are plannning on shooting lighter bullets I'd look for one with a 1 in 12 at least. I'm not sure how heavy a bullet a 1 in12 will stabilize but probably not over 60 grains. I'm sure one of the other twist rate gurus can shed some more light on this better than I can.

RJ

jpattersonnh
12-28-2006, 07:55 AM
Most of the guys I shoot with use 62..77gr in their 1in8.
I use a 1in9 and shoot everything from 55 grain to 70 grain. I can shoot heavier, but loose accuracy after 75 grains. I don't know if it matters or makes a differance, but mine is chrome lined.

baldtop
12-28-2006, 10:15 AM
Tikka makes their .223 barrels with a 1 in 8 twist. I like the idea of the heavier bullets for coyotes at long range. I also like the price of 45 grain white box Winchester .223 ammo. I want my cake, and I want to eat too.

unclenick
12-28-2006, 11:06 AM
8" twist will take you to 90 grain bullets unless the air is very dense (cold weather at low altitude). My service rifle match mouse gun has a 7.5" twist and I run the 53 grain MatchKings at 200 yards, the the 77's at 300 yards, then 80 grain Berger VLD's at 600 yards with no issues. having a fast twist for very short bullets will tend to exagerate any imperfections in their center of mass by increasing the eccentricity of their spin because their higher velocity means they spin at higher RPM. This means a mass axial error will make it jump a bit further to the side on muzzle exit than a slower spinning bullet of equal average density would.

Short bullets are able to tip more in a bore than long ones and have a poorer match to the throat angle, so they don't self-center as readily. A fast twist will cause such tipping to tend to create a larger initial coning motion and also gives any bullet a slightly higher angle of attack off the trajectory path, the resulting lift from which causes the bullet to fly a slightly helical path. This reduces the effective ballistic coefficient and with that comes increased wind drift.

Jim Boatright's two-part article, The Well-guided Bullet, in the September and October 2006 issues of Precision Shooting are recommended reading on this topic. Neck sized-only cases and, if it will reach, seating the small bullet out to touch the lands will both help with this issue. Moly impact plating (NECO method) of the bullets also reduces in-bore misalignment, which Boatright explains is why moly-plated bullets achieve better ballistic coefficients and wind bucking than bare bullets (on average). He references Walt Berger's study of their ability to align in the bore better.

In the end, the faster spin will be an added error source in firing short bullets, but you can take steps to compensate for that, as I described. The faster spin is esential for long bullet stability, especially in cold, low altitude weather.

baldtop
12-29-2006, 10:42 AM
Thanks Nick. Precision Shooting is a great magazine.
I am looking for a "walking around" .223 suitable for taking gophers, and coyotes, and punching paper. I have been looking at Stevens, Savage, Tikka, Remington SPS, CZ, and Weatherby Vanguard. Do you have an opinion on which might be best?
Thanks

John

Mush from PA.
12-29-2006, 07:44 PM
Thanks Nick. Precision Shooting is a great magazine.
I am looking for a "walking around" .223 suitable for taking gophers, and coyotes, and punching paper. I have been looking at Stevens, Savage, Tikka, Remington SPS, CZ, and Weatherby Vanguard. Do you have an opinion on which might be best?
Thanks

John

I have the CZ 527 American in 223. I shot 30 plus ground hogs with it in 2006. It is a great walk around varmit rifle. It is a ulitility rifle, not fancy but a good shooter. Mine seems to like (with quarter size accuracy at 100 yards) 45 grain UMC ammo (1 in 12 twist for the American). The 55 and 50 grain balistic tips do well in it too.

Give it a look and see if it fits you.

unclenick
12-30-2006, 01:49 PM
. . . I have been looking at Stevens, Savage, Tikka, Remington SPS, CZ, and Weatherby Vanguard. Do you have an opinion on which might be best?. . .

The Remington or Savage can be made to be extremely accurate, but you cannot count on them being super-duper right out of the box. Some will be, some won't. They will cost you less than, say, a Steyr, which, like many European guns, comes with a proof of performance group attached to the owner's manual. However, the less expensive domestics may end up having to make a trip to the custom gunsmith, which imposes the associated delay before you get all you can out of them.

I don't own any Weatherby's, but would expect the same to be true of them and certainly of the Stevens as well, just from reading posts. Since I have machine tools and can work on my own rifles, I gravitate toward the Savages for flexibility. Since I know I am going to invest in modifying and tinkering anyway, the comparative ease of changing barrels in that design has a lot of appeal. You need a barrel block set and an adequate vice or press, or else a proper barrel vice, a Savage type barrel nut wrench, and a chamber GO gauge to set the headspace. You can also change the boltface for total caliber changout. Nifty system, especially with the accutrigger. Other aftermarket triggers are also available.

If you are of a mind that you will tinker or have work done should you need it, then I would actually choose by going to the gun store and seeing how the guns fit you, ergonomically? Do they seem to come pointing on target when when you mount them? Is the stock the right length to keep your eye clear of the scope? Does it come up under your cheek for a good stock weld in prone, and not leave your face dangling, or, alternatively, push it away from the scope? If you assume an off-hand position with your fingers placed for your own best stability, does the weight distribution work well, or is it too nose or stock heavy to tend to stay in place? Then, of course, is the weight what you want? All that fun stuff to figure out.

If you don't want to tinker, you need either to buy a used gun you already know shoots well, or look at any rifle that comes with a test group. Again, check out the feel.

One other rifle you might consider as a compromise is the Browning A-bolt in a version with the B.O.S.S. That device, whether the solid or the brake version (not needed with .223 unless you are determined to use the scope to spot impact in real time), will let you tune muzzle vibration to tighten groups with specific loads. Between that and handloading, you should be able to make any A-bolt shoot extremely well. Mine in .30-06 tunes to under 1 m.o.a. with almost anything if I take the time, and will shoot under 1/3 m.o.a. with handloads.

baldtop
12-30-2006, 08:54 PM
I see why they call you "super moderator", Nick.

John

baldtop
12-31-2006, 04:11 PM
I like the idea of a muzzle break on the A-bolt, but it is not available in .223 Rem.

unclenick
12-31-2006, 04:20 PM
I see why they call you "super moderator", Nick. . .

Thanks. Would that it were so. However, the title is deceptive. It turns out to require a lot of fiddling with the forum software to assign someone to moderate specific forums, but assigning the more general "Super Moderator" status has proven to be quick and easy and does not eat up an evening of Marshall's time. I believe all newer moderators get this "Super" status for this reason, where just plain "moderator" actually means someone more experienced at the job.

Does look kind of nice on a resume, though. ;)

baldtop
01-01-2007, 04:24 AM
I think for the time being I will stick with my .308s. I have a Sako L581, and an Izhmash Los 7-1. They are both very accurate. I just bought a Burris Fullfield II 3 to 9 by 40 I want to play with. Also picked up some South African 7.62 ball I want to try on coyotes. Should keep me going for a while.

JBledsoe
01-01-2007, 06:17 AM
What can I do to make my 223 a little more accurate?


http://img136.imageshack.us/img136/8664/223target1206mj6.jpg (http://imageshack.us)



As you can see I had a flier in the first target. Will a cold barrel cause this? All targets fired at 100 yds. on clear calm day.

:D :D :D

Jim

I am really just trying to learn to post images and I think I have it now.

Hazcat
01-01-2007, 06:22 AM
What can I do to make my 223 a little more accurate?


http://img136.imageshack.us/img136/8664/223target1206mj6.jpg (http://imageshack.us)
I'd say you need to practice more. It looks like you only got 1 or 2 rounds on the target each time ;)

JBledsoe
01-01-2007, 06:25 AM
Would you believe all are five shot groups?

No?

Well, they are only three shot groups. But I AM pretty happy with that Benchmark (bottom two). 26 gr. and 50gr. V-MAX.

Hazcat
01-01-2007, 07:09 AM
Would you believe all are five shot groups?

No?

Well, they are only three shot groups. But I AM pretty happy with that Benchmark (bottom two). 26 gr. and 50gr. V-MAX.
Gee, ya think? Let's see, three rounds all touching (or better) at 100 yrds(?) and yer happy? Got some low standards there don't ya? (/jk)

Actually it looks like what I had to shoot too zero my M16 but that was at 25 meters!

unclenick
01-01-2007, 09:37 AM
. . . Well, they are only three shot groups. . .

You just may have found a sweet spot load for that rifle? Now you've got to start shooting groups of 10, like a real benchrester! Groups of 21 are needed to get the statisticians to believe you have established any real statistical significance. Man, your work is cut out for you. ;)

unclenick
01-01-2007, 09:56 AM
I think for the time being I will stick with my .308s.

I looked at the Browning site and was surprised not to find my .30-06 listed, either, but there it is in my closet. I'm pretty sure the .223 was available at one time, too. The B.O.S.S. system is something they bought out from an independent maker whom I recall advertising in Precision Shooting years ago. In principle it could be adapted to anything. (Compensators are put on .22 RF Short pistols for International rapid fire, after all, so anything is possible, even if not necessary.) But, then you will be in the land of custom work, so my original idea's value is mitigated.

Recently, another thread discussed an H&R Handi-Rifle in a caliber the maker doesn't list for it (.308). By coincidence, a friend of mine owns one in .30-06, also not listed on the web site. Not everything is. Some years they may make one set of chamberings, see the demand drop for some and change them the next year. You might try calling Browning and see if they can give you what you want without going to a separate custom smith’s shop? I've heard mixed things about their customer service, but what I’ve heard isn’t current and a phone call won't hurt the wallet enough not to be worth a try?