Is there really a difference between .223 and 5.56 ammo?

[zackmars]

eh, I think by the time of the SGW and Bushmaster ARs, the MIni-14 was starting to fade.

It's hard to explain, but the AWB and GWOT totally changed gun ownership. Way back when if you really wanted a semi with detachable box magazine, you had either a mini or m1 carbine. The AR still had a stigma around it from Vietnam. It took GWOT to break that, and when the AWB sunset, the floodgates opened.

There were plenty of AK's, AR's, Hk's and fals etc, but that's not really what you'd see at the range, in shops, etc.

 

[Sam7sf]

Truly was the time of fal’s

 

[Jim Lahey]

Yes, the shoulder, powder capacity and pressure

 

[TheMailMan]

There are many factors that come into play. The AR-15/XM16 was originally a 1:14 twist with a 55gr round (the .223 Rem and M193 were exactly the same back then). XM193 ammo today is not experimental surplus as with most X’s, but non Military ammo made using Military standards.

NATO ammo tends to have sealed bullets and primers (for wet conditions and to hold with full auto recoil and drops), and brass can be thicker (slightly less volume inside the case.

I can’t recall exactly the ranges, but the 55 Gr ammo is the most lethal of the military rounds. I know the magic FPS is 2700. I know a 20” M16 is effective (for the round to tumble and fragment) at 200 meters or less. With a 10.5” barrel it’s about 40-50 meters or less to be effective. The 16” to 14.5 is in between (like 150 meters to 100 meters max effective range for tumble/frag).

The SS109/M855 62 Gr NATO with 1/7 twist punches holes more than tumbles and frags. It was not as effective in combat as the 55 Gr M193. The M855A1 is more for penetration and consistency (along with being clean ammo). People wear more body armor and accuracy/penetration over injuries was a priority.

It is interesting the studies, myths, lore, history of the AR-15 and .223 Remington and what is has morphed into.

In 2008 we had good results with the Mk262 77gr hollow points in our M4’s, from Black Hills if I remember correctly.


View attachment 385262 View attachment 385263

I've always heard the original twist was 1:12.

 

[zackmars]

I've always heard the original twist was 1:12.

Original barrels were meant for .222 Remington and had a 1/14 twist rate. Us ord. Started moving goal posts and said that .222 rem wasn't powerful enough, so Armalite went to Remington, and thats how .223 Remington was born.

In the meantime, there were a bunch of
.222 barrels, so they simply reamed out the chamber to .223. The government realized that it was barely able to stabilize 55gr m193, so they went with 1/12.

 

[Kar98]

It's hard to explain, but the AWB and GWOT totally changed gun ownership. Way back when if you really wanted a semi with detachable box magazine, you had either a mini or m1 carbine. The AR still had a stigma around it from Vietnam. It took GWOT to break that, and when the AWB sunset, the floodgates opened.

There were plenty of AK's, AR's, Hk's and fals etc, but that's not really what you'd see at the range, in shops, etc.

Most people hadn't heard of it nor wanted one. It was Mini 14s, Mac Tens and FALs all around. Until Americans were told they couldn't have them... then suddenly AR's became popular.

 

[zackmars]

Most people hadn't heard of it nor wanted one. It was Mini 14s, Mac Tens and FALs all around. Until Americans were told they couldn't have them...

Fals really weren't that common either, not compared to mini 14's or 30's, sks's, and bolt and lever actions. They were certainly out there, but only "gun nuts" knew about them.

The AWB birthed the "casual recreational" shooter

 

[CavCop]

I've always heard the original twist was 1:12.

The XM16 was designed and issued as the M16 at first with a 1:14 twist.

“Remington’s famous 40XB bench rest (BR) rifle was offered with a 1:14 twist. This latter twist stabilized popular bullets used in BR matches that typically weigh 50 to 53 grains and were fired at targets within 300 yards, which proved to be a very accurate combination.”

Then got tighter to 12, 10, 9, 8, 7…

“The original M16 began with a 1:14 twist rate, which is good enough for bullets around 55 grains. The next step in the evolution was a 1:12 twist rate”

Age Verification - NRA

www.ssusa.org

 

[A1Oni]

The XM16 was designed and issued as the M16 at first with a 1:14 twist.

“Remington’s famous 40XB bench rest (BR) rifle was offered with a 1:14 twist. This latter twist stabilized popular bullets used in BR matches that typically weigh 50 to 53 grains and were fired at targets within 300 yards, which proved to be a very accurate combination.”

Then got tighter to 12, 10, 9, 8, 7…

“The original M16 began with a 1:14 twist rate, which is good enough for bullets around 55 grains. The next step in the evolution was a 1:12 twist rate”

Age Verification - NRA

www.ssusa.org

that's wrong, the early prototypes only had 1:14 barrels when they were under military trials they used 1:12 barrels
I'm an avid user of ARFCOM's retro forum which is a very rich resource on the AR15/M16's history.

 

[A1Oni]

Most people hadn't heard of it nor wanted one. It was Mini 14s, Mac Tens and FALs all around. Until Americans were told they couldn't have them... then suddenly AR's became popular.

people keep saying this crap and its plain untrue

 

[CavCop]

that's wrong, the early prototypes only had 1:14 barrels when they were under military trials they used 1:12 barrels
I'm an avid user of ARFCOM's retro forum which is a very rich resource on the AR15/M16's history.

You might check there and see if people there own 1:14 twist AR’s or M16 uppers that were issued out after trials and part of the original manufacturer (not the experimental). I think you will find 1:14 was issued and later 1:12 was used.

Project AGILE includes test results from the 1:14 twist M16 issued for use in Vietnam, and real world results on human targets from those killed by the 1:14 twist in Vietnam.

 

[A1Oni]

You might check there and see if people there own 1:14 twist AR’s or M16 uppers that were issued out after trials and part of the original manufacturer (not the experimental). I think you will find 1:14 was issued and later 1:12 was used.

Project AGILE includes test results from the 1:14 twist M16 issued for use in Vietnam, and real world results on human targets from those killed by the 1:14 twist in Vietnam.

early early rifles yes, but that was for a very short time. and it wasnt the m16 it was the colt 601

 

[CavCop]

early early rifles yes, but that was for a very short time. and it wasnt the m16 it was the colt 601

Interesting.

 

[A1Oni]

Interesting.

when curtils lemay wanted the AR15 rifle that was a bit after colt bought the rights from armalite and it was the Colt AR15 601 rifle the early models of the 601 had 1:14 twist but they quickly went to 1:12 twist for obvious reasons

 

[CavCop]

when curtils lemay wanted the AR15 rifle that was a bit after colt bought the rights from armalite and it was the Colt AR15 601 rifle the early models of the 601 had 1:14 twist but they quickly went to 1:12 twist for obvious reasons

View attachment 390185

My understanding was the XM-16 was issued as a select fire, full auto rifle with a 1:14 twist in Vietnam and later became the M16 with a 1:12 twist around the time non approved 30 round magazines started showing up, which i think had a full curve that was later changed to straight insertion.

I am not sure what Malaysia got issued in the late 1950’s but believe it was the semi auto AR-15’s.

 

[popsgarland]

Is y

Is your Mini 14 a Target Model? I think they are rated for only .223 Rem with only the Target model, but non NATO 5.56 on paper is .223 Rem and not 5.56 NATO.

My Mini 14 is the Ranch/Target model and has stamped on it...223 ONLY.

 

[zackmars]

My understanding was the XM-16 was issued as a select fire, full auto rifle with a 1:14 twist in Vietnam and later became the M16 with a 1:12 twist around the time non approved 30 round magazines started showing up, which i think had a full curve that was later changed to straight insertion.

I am not sure what Malaysia got issued in the late 1950’s but believe it was the semi auto AR-15’s.

Ar15, M16, XM16E1, M16A1, M16A2, M16A3/A4

initial "constant curve" 30 round mags were trialed pretty early, but had issues with fitting some lowers. Okay industries developed the familiar 30 round magazine somewhere around 1966 or 67

 

[A1Oni]

My understanding was the XM-16 was issued as a select fire, full auto rifle with a 1:14 twist in Vietnam and later became the M16 with a 1:12 twist around the time non approved 30 round magazines started showing up, which i think had a full curve that was later changed to straight insertion.

I am not sure what Malaysia got issued in the late 1950’s but believe it was the semi auto AR-15’s.

the XM16 is the Colt 602, which came after the 601 which the early models of 601s had 1:14 twist barrels then they moved to 1:12 twist and the XM16, which is the 602, had a 1:12 twist, no forward assist, then the 603 came along as the XM16E1 which also had a 1:12 twist barrel and forward assist the guns used in Malaysia were 602s

 

[A1Oni]

Ar15, M16, XM16E1, M16A1, M16A2, M16A3/A4

initial "constant curve" 30 round mags were trialed pretty early, but had issues with fitting some lowers. Okay industries developed the familiar 30 round magazine somewhere around 1966 or 67

you got it all wrong its >armalite ar15>601>602(XM16)>603(XM16E1)>604(M16)>614(M16A1)

 

[leVieux]

<>

Way back when, we called them “Stoner’s”, after their designer, Eugene Stoner.

see: https://ammo.com/articles/eugene-stoner-creator-ar-15-americas-rifle-forgotten-history

leVieux

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