If you must use 55 grain FMJ ammunition, you'll be hard pressed to find a better load than Hornady's.  The muzzle velocity of Hornady's load was 3088 fps from a 20" Colt barrel with a standard deviation  of 21 fps.  The pressure curve cycled the AR-15 action well.





It's currently loaded in new Winchester brass and charged with a short-cut extruded powder that tends to burn cleaner than typical ball powders. The words 55 grain FMJ and accuracy shouldn't be used in the same sentence, but the Hornady 55 grain FMJ bullet is the most consistently accurate bullet in that category that I have tested.

Since I'm being lazy and haven't searched yet, have you tested their steel cased training ammo that compliments their 55gr loadings?

I'm not surprised Hornady's bullets are accurate; I've compared them side-by-side with others (especially Winchesters) and found Hornady's to be WAY more consistent in their dimensions.  I'm also impressed by the "heel" in the Hornady jacket-there's a lot more jacket on the edge of the base, which seems to me would make for more consistent behavior when the bullet leaves the muzzle.

As always, great review.  Got some targets to show off?

Would these bullets tend to fragment in a fashion similar to M193 ?

Unfortunately my data on the 55 gain practice load was lost in a tragic boating accident.  (Actually it was a hard-drive crash.)

No.

Not of the factory load, but here's a couple of pics of groups from hand-loads using the Hornady 55 grain FMJ bullet to give you an idea of its potential.  The groups were fired from one of my Krieger barreled AR-15s.  You'll be extremely hard pressed to get any other 55 grain FMJ bullet on the market to match a 10-shot group like this.





Here's the group of the Hornady 55 grain FMJ hand-loads that the Internet Commando would have posted.




Off-topic:  here's something else you might find interesting GH.  link

That sucks

Do you remember what the rough accuracy of it was? 80% of my stash is 55 grain, so if I end up doing some training I'd like to use something slightly cheaper than normal brass .223/5.56 that would still be pretty accurate and would perform similarly to what I have stockpiled.

VERY interesting!  Thanks!

Please elaborate on some details

Nothing too detailed.  The jacket of the Hornady bullet is supposedly slightly thicker than other "M193" types.  More indicative, people have posted pics of the Hornady bullet failing to have any significant fragmentation in water, (which tends to over-emphasize bullet upset) which would support the claim of a thicker jacket.   Therefore, you can't depend on the Hornady bullet to fragment like genuine M193, which is rather undependable itself.  15% of the time, genuine M193 will display an early yaw cycle with fantastic fragmentation and temporary cavitation.  The other 85% of the time, not so much.  If anyone has the results of gel-tests for the Hornady bullet, I'm all ears as that is they only way that we will know one way or the other for sure.

I've heard the opposite.... that the Hornady 55 gr FMJ has a thinner than usual jacket... If I was wasn't so lazy (and cheap) I'd go cut up some bullets.

Also, can someone fill me in on the "boating accident" thing.... I understand it's a joke... I just wanna know where or how it originated.

I have a couple K of the brass cased Hornady 55 gr FMJ I keep in my stash and it's all loaded in new Hornady brass, I find it weird that they would use Win. brass for their new ammo. I like Win. brass and would not complain to reload it, just wondering why they would use Win. brass when they have their own.

Hornady does not make "their own" brass and therefore does not always have "Hornady" headstamped brass available.

I'll second the fact that these bullets are very accurate.  Sub one inchers out of my stock Del Ton upper.

Hornady does produce their own brass, however for high demand items like this it's easier to suppliment with an outsourced component.

In the least but not limited to; all Hornady-boxed unprimed component cases, 308 "Match" cased ammo (including 308 Win TAP), 6.5 Creedmoor ammo, 450 Bushmaster ammo, and Dangerous Game Series brass is all made by Hornady.

Can anybody confirm or deny this bit of info?

I was referring specifically to Hornady's commercially loaded ammunition with .223/5.56 brass that is the subject of this thread.  I even have some of their custom reloading cases for .223 that Hornady sells as components, but I was told that this is not the brass used in their commercial loads.  Is this true?  Every lot of 5.56 TAP that I've seen for the last few years has been headstamped with something other than "Hornady" (Winchester, Lake City etc.)  and of course the 55 grain load that is the subject of this thread has Winchester brass.  Does Hornady use their own in-house manufactured brass for any of their .223 line of ammunition?  If so, which catalog items would those be?

Also, the quote below is from "Kathy" at Hornady in reference to the brass used in TAP ammunition.  Is her statement true or false?

"We don't make this brass ourselves. We get it from several different vendors who make it for us and they all have their own headstamp."

All of my Hornady .223 FMJBT (50 rd boxes, about 2K rd's worth) & 40gr V-max ammo(20rd boxes, 500 rd's)are all loaded in the same Hornady brass you can buy as components in boxes of 50(which I have a few 100 of also), so it is indeed Hornady manufactured brass and not out sourced brass with different head stamps but I'm sure they have sold some using out sourced brass since their brass cost a good bit more than Win & LC.

How does their 55 gr shoot out of a 1/7?

Ok, thanks. When you say "type of projectile", are you referring to FMJ? Is it the fact that it's 55 gr make it less accurate or is it the way FMJ bullets are made? Also, have you compared the accuracy of the Hornady training steel case load to this round?

It's the fact that it is a .224" 55 grain FMJ bullet.  This "type" of projectile as a whole has repeatedly demonstrated a low level or accuracy compared to quality bullets of the same caliber and weight.  


Quality 55 grain bullets can shoot superbly from a 1:7" twist barrel. 55 grain full metal jacket bullets do not fall into the quality category, so any comparison made using 55 grain FMJ bullets with heavier open tip match bullets is nonsense.

The 10-shot group pictured below was fired from a distance of 100 yards from a Noveske barreled AR-15 with a 1:7” twist.  




The 3-shot group pictured below was fired from the same 1:7” twist barrel for the Internet Commandos in our viewing audience.






The next 10-shot group pictured was fired from a Krieger barreled AR-15 with a 1:7.7” twist.




Barrels with 1:7" twists can shoot bullets as light in weight as 40 grains without issue, as long as it is a modern, quality 40 grain bullet, such as the Hornady 40 grain V-MAX.





Here's another example of just how well a 1:7" twist barrel can shoot light weight bullets. While the group pictured below was fired from a distance of only 50 yards, it's a 10-shot group fired from a chrome lined, NATO chambered Colt barrel with a 1:7" twist using 52 grain Sierra MatchKings.




The 10-shot group pictured below was fired from a 20" government profile Colt barrel with a NATO chamber, chrome lining and a 1:7" twist. That's about as good as a group as you will see from this type of barrel and it did it with 55 grain BlitzKings.





Even a 14.5" Colt M4 barrel with its NATO chamber, chrome lining and 1:7" twist can shoot quality 55 grain bullets quite well.





Yet another example of how well 55 grain bullets can do from a 1:7" twist barrel. This time from the 16" version of the Noveske N4 light barrel that is also chrome lined and NATO chambered.







Here’s one last example of light weight bullets shooting well from a fast twist barrel. The projectile used this time was the 50 grain Hornady V-MAX.














The following demonstration compares the results of firing four 10-shot groups of the same lot of 55 grain Prvi Partizan M193 ammunition from two different barrels; one barrel with a 1:9” twist, the other barrel with a 1:7” twist.  The first barrel used in testing was 16” Colt HBAR with chrome lining, a NATO chamber and a 1:9” twist.  The second barrel used in testing was a 20” Colt HBAR, also with chrome lining, a NATO chamber and of course a 1:7” twist.  The longer barrel with the 1:7” twist was purposely chosen for the increased muzzle velocity coupled with the 1:7” twist.  Both barrels had free-float handguards.

Accuracy testing was conducted from a distance of 100 yards following my usual protocol.  The fore-ends of the weapons rested in a Sinclair Windage Benchrest and the butt-stock rode in a Protektor 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 attached to the objective-bell of the scope. Naturally, the wind conditions were monitored using a Wind Probe. The set-up was very similar to that pictured below.





Four 10-shot groups of the PPU M193 were fired from the 1:9” twist barrel.  Those groups were over-layed on each other using RSI Shooting Lab to form a 40-shot composite group.  The mean radius of that composite group was 1.08”.  

As with the 1:9” twist, four 10-shot groups were fired from the 1:7” twist barrel.  Those groups were also also over-layed on each other to form a 40-shot composite group that had a mean radius of 1.01”.  The two composite groups are shown side by side for comparison.






So much for the often posted nonsense about 1:7” twist barrels making 55 grain FMJ bullets “unstable.”

I do not know how scientific this may be, yet here is an image and some numbers for you.  The following projectiles were placed in a mill and 0.0840" was cut away.  This was as low as I could get with a solid hold on the bullets and not crash the cutter.

Bullets from left to right:  Hornady 55gr FMJ, Berger 55gr Target, Berger 70gr VLD, Prvi 75gr OTM.


The jacket thickness for each projectile is:
Hornady 55gr FMJBT:  0.0280"
Berger 55gr Target: 0.0205"
Berger 70gr VLD:  0.0240"
Prvi 75gr OTM:  0.0250"

Of this small sample, the FMJBT does have a slightly thicker jacket.  I ran out of the PMC FMJ bullets for reference.

Another rather critical issue is the heel of each of the bullets shown.  Hornady's FMJs have a very consistent heel with a smooth radius, which puts them head and shoulders above say Winchester's bulk 55s.  But the other bullets' bases and heels are very important-note how much more consistent each is than the FMJ-which is due to the construction method used in making the FMJ in the first place.  I wonder if any firm could be induced to make "TMJ" .224" bullets, similar to Speer's "totally jacketed" pistol bullets.  In that sort of construction, you get both a smooth and very consistent base but a closed and perhaps more penetrating point at the same time...and maybe more inherent accuracy than the modern FMJ can manage.

All of my Factory loaded Hornady ammo is in Hornady Factory made brass, I guess some places or lines of ammo gets the cheaper Win or LC brass to cut cost but you would think the brass they made would be cheaper but SSA also now uses LC brass instead of the SSA .223 brass shown in one of your pic's which I've never even seen before until now.

Head stamp pic


50 pieces of new Hornady component reloading brass and 50 pieces of Hornady Factory loaded 40gr V-Max I pulled the bullets on.


Some of the stash, all loaded with Hornady brass just like their component reloading brass.

I was told by Lt Colonel Chuck Santose That M193 specs doesnt call for a certian jacket type to be used?  
But that was back 10years or more?


 For those who dont know Chuck S. he help with the 50Y zero  info thats here on AR15.com

I would like to see


M4 w/ 1/7 twist &WIN USA 45grHP etc!


I just havent found the 45gr bullets to blow up

False.  There is an entire drawing dedicated to the M193 bullet specs with requirements for jacket thickness, bullet length, meplat diameter, cannelure location, etc, etc,.  Even the composition of the copper alloy used for the jacket and the lead used for the slug have mil-spec requirements.

Excellent work!  The M193 spec for jacket thickness is 0.021" with a tolerance of - 0.002", so your work supports the claims that the Hornady FMJ jacket bullet has a slightly thicker jacket than M193.

Hornady's "Frontier" headstamped brass was made by Prvi.

I feed my 1:7" LMT the Hornady 55 GR FMJ bullets with 25.5 GR of benchmark powder and they shoot consistently 1.5 MOA with a 3X scope (10 rounds).  Benchmark looks exactly like the powder in the picture that Hornady uses.  It could also be H322, but I doubt they would get those velocities with H322, so I am pretty sure it is Benchmark Powder.

Even though I had little to no interest in 55gr. fmj info.....I figured what the heck, Molon's post are always at least a good read......that sure nuff holds true every time and in this brief thread I found some tasty lil nuggets of knowledge that were unexpected based on the thread's title.

Really good info as usual Molon....thanks for sharing

And how is it that you know for a FACT, that the Hornady brass sold as a component is the exact same brass used in their factory loaded cartridges?  You’ve posted absolutely no proof supporting that statement.  

On the other hand, I’ve weighed the Hornady component brass and the Hornady headstamped brass used in their factory loaded cartridges.  The component brass has an average weight of 89.5 grains, while the brass used in their factory loads has an average weight of 93.8 grains.  That’s a difference of 4.3 grains, which is a big difference for .223 cases and a good  indicator that the component brass and the factory loaded brass that I compared is not from the same source.  

Also, I’ve posted pics three times now of Hornady factory loaded ammunition that has headstamps from Frontier, Winchester and Lake City; so Hornady does indeed outsource a good deal of the brass used in their .223/5.56mm factory loaded ammunition.  As I previously posted from “Kathy” at Hornady:

"We don't make this brass ourselves. We get it from several different vendors who make it for us and they all have their own headstamp."






Again, you make statements without posting any supporting proof.  Do you understand that just because a case is headstamped “Hornady” does not mean that said case was manufactured by Hornady?  How is it that you know for a FACT, that Winchester and Lake City brass is “cheaper” than the Hornady headstamped brass used in their factory loaded ammunition, when you haven’t even proven that the brass used in their factory loaded ammunition is the same brass sold as a component?