5.56mm (223 rem) Heavy or light bullet?

[Norwegian Viking]

I have a Steyr AUG with a 20" barrel , the barrel twist is 1:9 ,what should i use to improve accuracy?

I have used factory loads up untill now (American eagle 55gr and UMC 55gr) , and these have had deesent accuracy.

But i hear from a friend that i should use heavyer bullets for the 1:9 barrel twist , anyone have any experience on this they would like to share?

[uscbigdawg]

I have zero experience with a Steyr, but imagine, it’s gotta be close (balistically speaking) to a 20” AR barrel. With a 1:9 twist, you can use anything from 55’s up to 69’s and get good solid accuracy. Now, that’s based on an AR barrel, that’s say button rifled with 6 grooves. This may be different in your case and results may vary. When in doubt, try Black Hills.

Hope that helps.

[Gun Geek]

First question is what do you mean by decent accuracy? If you're getting MOA or better (1" at 100yds) it will probably be tough to improve.

What kind of shooting do you do? Up close tactical or long range varmint/target shooting?

Also, twist rate generally sets a maximum weight. Any bullet lighter than that maximum should work fine (there are some special cases that are exemptions)

Changing bullet weight won't neccesarily make the gun more accurate.

You MAY find a factory load that is heavier that your rifle likes better than your current ammo, you may not.

What a heavier bullet will get you is better resistance to wind, and will retain energy better for longer shots.

You might experience more recoil with a heavier bullet.

[Norwegian Viking]

I use the rifle for IPSC shooting , so it's a little of both (long and short range).

The accuracy is about MOA ,but very often not within MOA , kind of in the twilightzone( ).

[TRG65]

I have been trying various bullet weight from 52 to 75 for my 1 in 9 twist AR. I found that the 60 grain bullets are by far the best (I was using the Hornady 60 grn V-Max). When I called Bushmaster, they said the optimium weight for the 1 in 9 is 62-63 grains.

[Norwegian Viking]

What kind of powder and powderweight do you use with your loads?

BTW: Picture of my presious.

http://privat.bluezone.no/traenge/Bilde1.jpg

[ErikW]

A 1:9 twist rate will stabilize all the way up to about 75 gr. The general weight is not as important as quality construction and consistent weight per bullet. The best accuracy usually results from match bullets and varmint bullets. The more general-purpose bullets (FMJ, soft point) generally don't shoot nearly as well. Try something like the Lapua Scenar, Sierra MatchKing, etc.

There are many, many powders that will work well. I'm not sure which are available in Norway. Vihtavuori N135, W748, 4895, Varget, etc.

[TBF]

Not to forget H335 a fine accuracy powder IMHO.

Meters well too.

If you can't find a Sierra Matchking shooting well out of your barrel, you have a strange gun indeed.

Travis F.

[uscbigdawg]

What Travis said.

Rich

[TBF]

What Travis forgot to say,

Very few 223 rifles refuse to shoot 52 gr. Matchkings well.

If they are not prohibitively expensive where you are try them.

Never used the 53 gr. version, but some of the bench guys love it.

I have heard it said that 69 gr. is about the heaviest bullet a 1:9 barrel will shoot well, but then I heard Derrick Martin ( of accuracy speaks ) is getting good results with the heavy stuff.

I cannot confirm or deny that, my 1:9 barrel is not really that accurate with the 69 gr. bullet, but my 1:8 loves it. Might be worth testing if you have a lot of long range targets ( 250 + yards )

Travis F.

[ppro]

This is a fairly late reply to your post, but probably usefull information anyway.

There have been some fairly tests using common AR twists rates like 8 and 9...and in general, they found that the lighter bullets were generally more accurate.

My tests generally bear this out. Though I can get good accuracy with the different heavier bullet weights one thing very IMPORTANT to consider, is how quickly you can get back on target.

If you don't NEED the bullet weight for any particular reason, then by all means, try the lighter bullets.

My fastest RECOVERY and most accurate load for all positions, is with a Nosler 40 gr. ballistic tip. As always, harmonically tune. I cheat, and use a tuner on my ar barrel so accuracy tuning is very easy. I have gotten 3/8 MOA @100 in three different ar's with the 40 gr. ballistic tip....and the b.c. is quite high for the bullet weight.

If time on the clock matters, definately try the 40 gr. and check your recovery time.

just some thoughts.

Paul

[reneet]

Jim Clark Jr has told me that the 1 in 9 will stabilize from 45 - 69 grain bullets.

[cking]

I think he looking for canned ammo. What your seeing is not unusual with those brands. I call it a flyer per group.

To see what gun can do. Scrub the bore clean. and shoot a little federal match. Then you will probably be the limiting factor.

[ppro]

Reneet

I am not sure what your point is on the twist.... a group of us also use are AR's for varmint shooting at all ranges to a max of 400, plus combat comp and all of us are using the 40 gr. Nosler ballistic tip becuase it so accurate in them and high b.c. (comparitively)

Regardless of what you were told, the 40 gr. Nosler is extremely acurate in the above weapons....all 1/9 twist and accurate to long range(winds not withstanding).

If your saying that the 1/9 shouldn't or won't stabilize the 40 gr. Nosler ballistic tip, well, I beg to differ.

I have tested the Nosler 40 Ballistic tip bullet, in heavy barrel DPMS, COLT match, COLT std. 20", BUSHMASTER VMatch, and BUSHMASTER Varminter, DPMS Sweet 16, COLT 16" and it did VERY well. Not much I can add excpet that they are a little pricey compared to other bullets, but for our applications,....worth it.

regards

Paul

[n2ipsc]

What Travis forgot to say,

Very few 223 rifles refuse to shoot 52 gr. Matchkings well.

If they are not prohibitively expensive where you are try them.

Never used the 53 gr. version, but some of the bench guys love it.

I have heard it said that 69 gr. is about the heaviest bullet a 1:9 barrel will shoot well, but then I heard Derrick Martin ( of accuracy speaks ) is getting good results with the heavy stuff.

I cannot confirm or deny that, my 1:9 barrel is not really that accurate with the 69 gr. bullet, but my 1:8 loves it. Might be worth testing if you have a lot of long range targets ( 250 + yards )

Travis F.

<{POST_SNAPBACK}>

I'd second this. 52gr or 53gr Sierra M/K's shoot comfortably under an inch at 100 in my 8.5/1 and 9/1 barrels (the 53's usually go more on the order of 5/8"). 2940 or so seems to be the sweet spot, velocity-wise. Try 25-25.5gr of Varget and spark 'em with a Fed 205 GM Match primer.

I'd also second the 69's. My 1:8.5 is marginally better than the 1:9, but they're both around 1-1/8" to 1-1/4" at 200 yds. 24-24.5gr of Varget works well.

[reneet]

I am not sure what your point is on the twist....  a group of us also use are AR's for varmint shooting at all ranges to a max of 400, plus combat comp  and all of us are using the 40 gr. Nosler ballistic tip becuase it so accurate in them and high b.c. (comparitively)

Regardless of what you were told, the 40 gr. Nosler is extremely acurate in the above weapons....all 1/9 twist and accurate to long range(winds not withstanding).

If your saying that the 1/9 shouldn't or won't stabilize the 40 gr. Nosler ballistic tip, well, I beg to differ.

regards

Paul

<{POST_SNAPBACK}>

Paul,

Appreciate the info. What I was saying is that based upon the 1 in 9 twist barrel that are in CCG Inc Gator Rifles and Jim's own personal experience, he recommends that weight range for our 1 in 9 twist barrel. When he returns from the 2 sniper championships he's shooting this week, I will definitely pass this information along to him and see if he wants to modify his recommendation.

Renee

[BigDave]

Does anyone shoot 52 gr bullets out of a 1/9?

[reneet]

Jim and Jerry both shoot 52 grain (Hornady A-Max primarily) out of 1 in 9 twist barrels.

[BigDave]

Cool - thanks Rene. I've come a across a local loader who loads up 52's regularaly. I'll give em a shot (pun intended) in the Gator.

[jwrig]

Jim Clark Jr has told me that the 1 in 9 will stabilize from 45 - 69 grain bullets.

That's what I've heard. Haven't tried anything heavier than a 69 SRA HPBT or lighter than a 52 SRA. They both worked well for me.