I've been trying to do research whether this IMI Systems 5.56 (55 grain FMJ) ammo is good to use but only found that "any ammo after mid-2016 is good" given that before they were loaded at max specs.

How do I determine if the ammo I have is good and not "too hot"?

I did not expect the images to load so large.

The lot number 00219/H printed on the box might be a clue you can search out.  What is the exact marking on the base of the cartridge (called the headstamp)?  I think it will be "IMI" and a number.  I've shot a lot of IMI 5.56 and never had a problem with it.  This should be fired only out of a gun chambered for 5.56mm, do not fire in a gun chambered for .223.  5.56mm is higher pressure than .223

You can soundly ignore whoever told you that stupid shit.

IMI M193 Accuracy Over A Span Of 15 Years




I started shooting M193 ammunition produced by Israel Military Industries (IMI) in the year 2000.  At that point in time, IMI was still using their headstamp of “TZZ”.  I first noticed the “IMI” headstamp on a 2002 lot of this ammunition.








Unfortunately, much of my early test data for IMI M193 was lost due to a tragic boating accident (hard drive crash actually), so the accuracy/precision data for this article will start with a lot from 2006.

The accuracy specification for M193 cited in MIL-C-9963F is as follows:

“The average of the mean radii of all targets of the sample cartridges, fired at 200 yards, shall not exceed 2.0 inches.”

These averages are from 10-shot groups fired from machine rested, bolt-actioned heavy test barrels.  All things being equal, this specification equates to a mean radius of 1" at 100 yards.  All testing for this article was conducted at a distance of 100 yards (verified with a laser range finder).

The accuracy (technically, precision) evaluations of the IMI M193 ammunition were performed following my usual protocol.  These accuracy evaluations used statistically significant shot-group sizes and every single shot in a fired group was included in the measurements. There was absolutely no use of any Group Reduction Techniques (e.g. fliers, target movement, Butterfly Shots).

The shooting set-up will be described in detail below. As many of the significant variables as was practicable were controlled for. Also, control groups were fired from each barrel used in the evaluations using match-grade hand-loads.  As an example, the 10-shot group pictured below was fired from the 20” Lothar Walther barrel at a distance of 100 yards using a hand-load topped with the Sierra 52 grain MatchKing.  The group has an extreme spread of 0.58”  In all cases, the extreme spreads and mean radii of the control groups were significantly smaller than those of the ammunition being tested.





All shooting was conducted from a concrete bench-rest from a distance of 100 yards The barrels used in the evaluations were free-floated. The free-float handguards of the rifles rested in a Sinclair Windage Benchrest, while the stock of the rifles rested in a Protektor bunny-ear rear bag. Sighting was accomplished via a Leupold VARI-X III set at 25X magnification and adjusted to be parallax-free at 100 yards. A mirage shade was used. Wind conditions on the shooting range were continuously monitored using a Wind Probe. The set-up was very similar to that pictured below.




The Wind Probe . . .




2006

The 2006 lot of IMI M193 was tested using a chrome lined, NATO chambered 20” Colt HBAR with 1:7” twist.  





The average extreme spread for three, 10-shot groups fired in a row was 2.48”.  The three, 10-shot groups were over-layed on each other using RSI Shooting Lab forming a 30-shot composite group.  The mean radius for the 30-shot composite group was 0.72”.  The 30-shot composite group is pictured below.




2007

The 2007 lot of IMI M193 was also tested using a chrome lined, NATO chambered 20” Colt HBAR with 1:7” twist.  The average extreme spread for three, 10-shot groups fired in a row for this lot was 2.65”.  The 30-shot composite group had a mean radius of 0.94”.





2009

The 2009 lot of IMI M193 was tested using a chrome lined, NATO chambered 16” Colt HBAR with a 1:9” twist.  This 2009 lot is the same lot that I tested for my 2010 article

Attack of the M193 Clones





Three, 10-shot groups fired in a row had an average extreme spread of 2.80”.  The mean radius for the 30-shot composite group was 0.97”.





2011

The 2011 lot of IMI M193 was the most consistent lot of this ammunition that I’ve tested.  The barrel used to test this lot was a 20” Lothar Walther stainless steel barrel with a 223 Wylde chamber and a 1:8” twist.  





While it is sometimes possible to obtain slightly better accuracy from mil-spec/NATO pressure ammunition by firing it from an AR-15 that has a stainless steel match-grade barrel with a hybrid chamber, such as the Noveske Match Mod 0 chamber or a 223 Wylde chamber, you're not going to make a silk purse out of a sow’s ear doing this.  

This lot of IMI M193 was so consistent in preliminary testing, that I decided to fire eight, 10-shot groups in a row for the formal evaluation.  The average extreme spread for the eight, 10-shot groups was 2.07”.  All eight of the 10-shot groups were over-layed on each other to form an 80-shot composite group.  The mean radius for that 80-shot composite group was 0.64”.




2021

Skipping ahead 10 years from the previous lot tested, the IMI M193 ammunition is still performing like it did with the previous lot.  This lot was also tested using the 20” Lothar Walther stainless steel barrel with a 223 Wylde chamber and a 1:8” twist.  The average extreme spread for three, 10-shot groups fired in a row was 2.31”.  The mean radius for the 30-shot composite group was 0.65”.







…..

The ammunition is made to kill people, not for target shooting.

I can assure you it will do the job just fine with reasonable accuracy.

@ Molon:  
As usual a great write up............. but............ and I'm not the OP............
Some posters are concerned about the velocities of these various ball rounds, not necessarily the accuracy.  
Or more precisely that the velocities reflect ammunition that is too hot or not "hot enough."
And they are laser focused on that due to questions of terminal ballistics.  


@OP:
There is a fellow here.............. maybe Blain? that follows all these up/downs of these loads......... maybe he will post.
In the meantime as the other Poster asked:  What are the head stamp markings?

it sounds like the OP has bought into the internet rumor that pre-gimped IMI is 'bad' because it's it was at the higher end of the pressure/velocity spec

2010




2021



......

Thanks everyone. I was actually mostly concerned about whether they were safe to shoot hahaha.

@molon thank you for the incredible write up and to everyone else.

Head stamp mark incoming.

Damn it, image is failing to load and have to run an errand.

Will upload picture later but see below for headstamp info
- Top is IMI
- Right is 9
- Left is 1
- Bottom is 16

Like this, but yours has a 16 instead of 21?  If so, your lot is from 2016.



....

Yes like this. Guess they’re made in 2016 then.

Thank you molon.

OP:
Yes............ you have 2016 yr production IMI.
FWIW:  I've never had an issue with the IMI I shoot.  
Assuming your rifle is somewhat decent, I wouldn't expect any issues.  
Enjoy!

@Molon:
As usual............. thanks for information!

Headstamp was promised - sorry for delay. Thanks everyone.

Thanks for taking the time to test this ammo @Molon.  Greatly appreciated.

When I worked at an indoor range in a resort town between 2013-15 the customers shot LOTS of blue-and-white box Independence ammunition through our rental carbines and a SAW.  It was made in Israel and I believe imported by Federal.  I can't remember the headstamp but I seem to remember it was maybe IMI?

That stuff was HOT and flashy, occasionally dropping primers from 16-inch barrels.

Made for Federal via a contract with Federal to Federal's specifications.



...

Attached File

I have a bunch of 2009-2012 in the same boxes.
They came in 1200rd cases (I first saw it at Wideners) for $316 for M193 and $336 I think for M855
I shot a lot and still have some. It does just fine in a quality AR.

Hell, someone will probably pay you $0.70cpr now since its "Pre-Neutered" "Tru-Mil-Spec" and "Dipped in Pig Fat".

Edit: Just saw the headstamp photo. The 19 is a machine/line number. Other cases in the same box should have other numbers there. The 16 is the Year.