Looking for real world experiences with light .223 in AR

[Mr_Flintstone]

Not exactly light loads, but light bullets. Has anyone here successfully loaded and shot 45 grain or lighter bullets from a 1:7 twist carbine? Reading the lore about 1:7 twist AR 15 rifles would lead one to believe that anything lighter than 62 grains would spontaneously explode in flight, or go hurtling in wild directions into space. It has been my experience that 55 grain loads shoot perfectly fine in my 16" PSA, but I have never shot anything lighter. With times what they are, I began wondering what actual results people have had shooting lighter bullets from their ARs. I know they aren't optimal, but has anyone had any positive results?

 

[forty_caliber]

This might help you....

https://bergerbullets.com/twist-rate-calculator/

.40

 

[AJC1]

A guide to go by is rpm. If you get a bullet spinning faster than 300k rpm their survival drops quickly.

 

[AFDoc]

I’m interested in this as well. It would be fun to have a small game load approximating the 22 Hornet that will also cycle the AR’s action.

 

[Mr_Flintstone]

This might help you....

https://bergerbullets.com/twist-rate-calculator/

.40

A guide to go by is rpm. If you get a bullet spinning faster than 300k rpm their survival drops quickly.

I’ve seen those things too. Specs are good to go by, but I’m interested in what actually happens when the rubber hits the road (so to speak). Surely somebody on the forum has tried this, and either had good results or found the internet chatter to be valid.

 

[Bfh_auto]

I've run 35 gr hornet bullets in a 1-8 AR. I didn't shoot anything with them. They have the bc of a wiffle ball. So I got bored quickly.

 

[guzzi]

I have used SinterFire 42gr bullets which are frangible out of a 1:7 223 with no problems. This was using 24gr of IMR4895.

Well, there is a problem. Shooting steel at 100 yards I was unable to hear the impact. But shooting paper showed that they did indeed go that distance intact.

These bullets would turn into something like talcum powder on impact with steel.

 

[jmorris]

Depends on the bullet an FMJ isn't likely to come apart no matter the twist. I have seen thin jacket varmint bullets, intended for 1:14 barrels disintegrate upon exit of a 1:7 barrel though. They were speer 52 grain.

 

[NMexJim]

This is a pretty simple chart. I've always tried to match bullet weight to the twist rate. That, at least, gets you in the ballpark without having to worry about over or under stabilization. But that said, my AR 1:7 loves 55 grain and 62 grain. I have not tried any weights under 55 grain, but I certainly would if I had a need.

Some of the original issues with the M16 was indeed with twist rate and came to light in Vietnam. Keyholing was a bigger problem than "exploding" bullets - or maybe it was keyholing that resulted in exploding bullets. Whatever. The twist rate was changed, and the M16 and variants thereof have been with us a very long time now. I think a lot of us think it's time for the US to move into a rifle with a little more range inherent to it's capability.

I quote Gunivore fyi: "Originally, the M16 rifle had very different rifling: right-hand twist, 4 grooves, 1:14. Later, the grooves became 6. Currently, the twist is 1:7. Civilian M16-dopplegangers have a twist rate of 1:9."

BTW, I'm liking CFE223 for just about everything.

 

[kcofohio]

I shot some, either 45 or 50 gr. Winchester varmint factory loads out of a 24" 1-8" twist barrel once. At a 100 yrs, they made it to the paper and grouped decent enough. I was trying them, after using some 55 gr. FMJBT rounds to zero in a new scope.

 

[jmr40]

I don't handload for 223, but I've gotten very good accuracy with 50 gr bullets in my 7 and 8 twist rifles. Specifically these.

https://www.midwayusa.com/product/1836125052

The box in the photo says 55 gr. They make both, just wrong photo for this product. I've only used the 50 gr loads. Before things got crazy I could get them at Cabelas @ $25/50 rounds. Most accurate loads in my 223/5.56 rifles regardless of bullet weight. Fortunately I have several hundred put back.

 

[call1911]

Oberland Arms Match Bull Barrel 24"
1:7 twist
Sierra 40gn or Nosler also 40gn, both with the plastic tip.
Vihtavuori N130
Brass weighed 105gn (+/- 0,5gn)
5 Shot groups
11-15mm at 100 meter

But: a little wind and they are blown away

 

[Blue68f100]

I have 3 223 R with 1:8, 1:9, 1:10 twist, all heavy bull barrels. And a 1:7 in a 224V
I base accuracy as good 1 moa, really good < 1 moa.

The 1:8 would not shoot anything less than 62 accurately. 1.5-2+ moa at 100 yrds with 55gr match grade bullets.
1:9 will shoot 53gr to 69gr with no problem. 1 moa or less depending on my bullet selection.
1:10 is best with pills lighter than 60 gr. < 1 moa using 52gr SMK

 

[NMexJim]

I have 3 223 R with 1:8, 1:9, 1:10 twist, all heavy bull barrels. And a 1:7 in a 224V
I base accuracy as good 1 moa, really good < 1 moa.

The 1:8 would not shoot anything less than 62 accurately. 1.5-2+ moa at 100 yrds with 55gr match grade bullets.
1:9 will shoot 53gr to 69gr with no problem. 1 moa or less depending on my bullet selection.
1:10 is best with pills lighter than 60 gr. < 1 moa using 52gr SMK

Second this. For best accuracy, twist match is a good thing. If I were to buy another barrel, it'd be a 1:9 since 55 grain is a favorite.

 

[2ndtimer]

I have shot 40 gr Nosler Ballistic Tips and Varmageddons, as well as Hornady V-Max in both handloads and factory ammo in my Stag Model 6 24” 1 in 8” twist, as well as in my S&W original Sport 16” 1 in 8” twist with excellent results, both in group size and performance on Montana gophers and prairie dogs. I have also shot them in a PA-15 18” 1 in 7” twist and had good accuracy with Fiocchi Extrema ammo with 40 gr V-Max bullets. Of course, your barrel may be different but that has been my personal experience.
I was concerned that they might not reliably function in an AR, but have had no issues other than some Nosler factory 40 gr Ballistic Tips occasionally not locking the bolt back on an empty magazine in rifle length gas systems.

 

[berettaprofessor]

I have a 1:8 twist bull barrel Stag AR that shoots 52 grain Hornady ELD in one hole at 60 yards. No disintegration noted. Yet a 1:9 Savage doesn't like those bullets and prefers a 62 grain match bullet. Who knows? Match the bullet to the barrel.