While there may not be any 5.56 ammunition on the shelves right now, the question when it does become available again (and it will) is which type to buy. What ammo will give you the best bang for your buck? And which brand of ammo will leave you trying to find the broad side of a barn? To answer that, we bring you a series of articles to try to find the most consistent ammunition out there . . .
Here’s a quick reminder of what’s going on: we run 20 rounds of each brand through a chronograph and look at the IQR or InterQuartile Range to get an idea of how tight the group is going to be downrange. There are plenty of other factors in accuracy, but velocity is the only one that’s “clean” enough to calculate and compare (as everything else can be influenced by the shooter, equipment, etc.). For the full methodology check out this article. Just remember LOW = GOOD and we’ll be on the same page.
We’ve changed guns since the series started, moving from a Rock River Arms National Match AR-15 to a Noveske 18″ SPR rifle, but the effect of that change seems negligible. Before running this current test I ran 10 rounds of XM193BK through the chronograph and (even despite the difference in pressure, altitude, temperature and barometric pressure) the interquartile range was within an acceptable margin from the original test. The velocity was a touch lower, but that’s what happens when you have 2 fewer inches of barrel.
First on the block today is Winchester’s (well, technically Odin Corp, but Win owns them) M855 ammunition. This green tipped, steel core ammunition is one of the standard loads for the U.S. armed forces (DODIC A059) and produced in staggering numbers. The steel core makes it persona non grata at many ranges and shooting competitions due to its penchant for punching through steel plates, but for self defense (/ SHTF) ammunition or punching holes in paper its nice to have a cheap and accurate option. But exactly how accurate is it?
Also up for testing is Freedom Munitions’ 55 grain 5.56 round. Freedom Munitions is a rather large sponsor of the local range, and produces ammunition (re-manufactured from parts) right here in Texas at a reasonable price. But does that reasonable price come at the expense of smaller groups?
As usual, the first boxplot is nearly useless.
Without normalizing the chrono data, its pretty hard to draw conclusions about the ammunition’s consistency. But what is of particular interest to me is that the M855 ammunition is a good 100 – 200 feet per second hotter than the 55 grain flavor, which means higher chamber pressures and increased barrel wear.
I guess there’s a reason the U.S. Army manual recommends using M855 ammo in the M16A2 platform only in emergencies. That stuff looks like it can wear your barrel out faster than my Dad can wolf down Chinese food.
This right here was damn surprising. So surprising that I’ve got 20 more rounds and I intend to double check the results (the fliers make me worried). From these results, the M855 ammunition is the most accurate ammo I’ve ever tested. Ever.
What makes me happy, though, is that you can see the bell curve developing. A couple good brands, a couple bad brands, and a whole lot in the middle. I’ll re-confirm the results and get back to you, but in the meantime these are the results.
| Brand and Weight | Caliber | IQR | $/round |
| Winchester / Odin M855 62gr Penetrator |
.223 Rem | 9 | $0.50 |
| Wilson Combat 77gr Sierra HPBT Match |
.223 Rem | 19 | $1.52 |
| Wilson Combat 65gr Sierra SP BT |
.223 Rem | 21 | $1.52 |
| Hornady Steel Match 75gr BTHP Match |
.223 Rem | 25 | $0.44 |
| Hornady 75gr BTHP Match |
.223 Rem | 29 | $0.79 |
| CorBon 69gr HPBT |
.223 Rem | 30 | $1.18 |
| Remington Premier Match 77gr BTHP |
.223 Rem | 36 | $1.50 |
| Winchester 64gr “Power Point” SP |
.223 Rem | 38 | $0.82 |
| Wolf 55gr FMJ |
.223 Rem | 40 | $0.21 |
| Federal XM193F 55gr FMJ |
.223 Rem | 40 | $0.32 |
| Pierce 55gr HP-BT |
.223 Rem | 42 | $?.?? |
| HPR 75gr BTHP Match |
.223 Rem | 43 | $0.50 |
| Nosler Varmint 40gr Ballistic Tip |
.223 Rem | 44 | $0.86 |
| Handloads – 20.8gr N-135 75gr Hornady HPBT Match |
.223 Rem | 49 | $?.?? |
| Handloads – 21gr IMR 3031 75gr Hornady HPBT Match |
.223 Rem | 52 | $?.?? |
| Winchester PDX-1 60gr SC-HP |
.223 Rem | 58 | $1.45 |
| Freedom Munitions 55gr FMJ-BT |
.223 Rem | 66 | $0.42 |
| American Eagle 55gr FMJ-BT |
.223 Rem | 68 | $0.30 |
| Brand and Weight | Caliber | IQR | $/round |
| Remington UMC 115gr | .300 BLK | 20 | $0.52 |
| Remington AccuTip Premier 125gr | .300 BLK | 20 | $1.39 |
| CMMG 147gr | .300 BLK | 26 | $0.78 |
| Remington Subsonic 220gr | .300 BLK | 27 | $0.92 |
| PNW M 155gr | .300 BLK | 28 | $0.90 |
| PNW D 220gr | .300 BLK | 54 | $1.08 |
| Brand and Weight | Caliber | IQR | $/round |
| Hornady Superformance Match 150gr SST |
.308 Win | 26 | $1.21 |
| Wilson Combat 168gr Sierra HPBT Match |
.308 Win | 28 | $1.99 |
| PMC Bronze 147gr FMJ BT |
.308 Win | 39 | $0.50 |
| SetPoint – 44gr Varget 150gr Hornady FMJ BT |
.308 Win | 52 | $1.74 |
| Prvi Partizan 150gr FMJ |
.308 Win | 54 | $0.82 |
| Remington “Managed Recoil” 125gr CORE-LOKT PSP |
.308 Win | 125 | $1.40 |