The .300 Blackout: even in non-suppressed ARs this quietly accurate .30-caliber thumper has a lot going for it.
It quickly became the darling of the tactical community, but good things are hard to keep secret. Many shooters realized the potential of the Whisper in single-shot arms like the Remington XP-100 and the T/C Encore and that it made a dandy hunting cartridge with properly constructed 110- to 150-grain bullets.
In 2011, Advanced Armament Corp. introduced its version of the cartridge, but called it the "300 Blackout," getting the cartridge approved by SAAMI in January 2011. While the target market for it is not completely clear at this writing, this development will surely further the use of the round, as factory ammo and cases are now available for what was heretofore a wildcat. Handloaders will have a field day loading ammo for this neat little concept cartridge. Best of all, Hornady has introduced .300 Whisper factory ammo and Remington has .300 Blackout loads.
While the .300 Whisper and .300 Blackout cases are virtually the same, the Blackout throat is a bit longer, so it's okay to use Whisper ammo in a Blackout, but Blackout ammo might not work in a Whisper. The 100-percent safe solution is, of course, to use only the ammo of the caliber that's stamped on the barrel. Also, Hornady states that its new .300 Whisper ammo is fully compatible with all .300 Blackout rifles, so this solves the problem, too.
Our test rifle this month is a brand new Hunter AR from Loki Weapons Systems, and it proved to be a real shooter. It sports a 16-inch barrel with a 1:8 twist (the better to stabilize long bullets at low velocities). The Hunter has what barrel-maker Steve Satern calls the "Russian" rifling system, in which the edges of the lands are beveled at 45-degree angles. I'm not sure about the technicalities of this, but I can tell you that it shoots great and doesn't pick up fouling, even after many rounds. We topped the Hunter off with a Bresser l-4x30mm scope in Weaver extra-high rings. Due to range construction, we had to test at 80 yards, instead of the usual 100.
Handloading the Blackout presents no unusual problems now, but back in the day, you had to form cases by necking up.221 Fireball cases. Today, we can either fire factory ammo or order preformed cases. We took the easy route and used Hornady cases and re-formed 5.56mm cases (bradswarehouse.com) with complete success. We used a new set of precision-made Forster Benchrest dies, and the proper shellholder is the same as for the.223.
Cartridge overall length (COL) is critical for proper functioning of the round in an AR. The fat .30-caliber bullets should be seated deeply enough so that part of the bullet ogive that's about.250 inch in diameter is behind the two ridges on the inside of an AR magazine. Otherwise, the rounds may fail to feed. Note the COLs in the load table. While they look "too short," they are just the ticket for this situation
Standard small-rifle primers are all that are needed for the small powder charges used by the Blackout. The petite case and high bore-to-case capacity ratio limit appropriate powders to "slow pistol" or "fast rifle" numbers like H-110, W-296, Lil'Gun and IMR-4227 from Hodgdon; 4100 and AA-9 from Western; 2400 and PP-300MP from Alliant; and Vihtavuori N-110. All performed excellently with several loads, but it's sometimes tricky to seat a longer bullet on a powder charge that almost fills the case. Remember, the lighter (and shorter) the bullet, the more room there is for powder, and the denser the powder, the better.
The emphasis here is on loads for hunting various species, and many great combinations were developed. Bullets weighing 110 grains delivered velocities in the neighborhood of 2,000-2,300 fps and would do well on varmints and small game, depending on bullet construction. The Hornady V-Max favored 17.0 grains of Vihtavuori N-110, while the Sierra HP of the same weight shot great over 18.5 grains of H-110.
Two bullets that make into great hunting loads are the Barnes Triple Shocks, well known for deep penetration and reliable expansion. Top velocity with the 110-grain TS was a sizzling 2,369 fps over 20.0 grains of W-296. The 130-grain version clocked 2,203 fps with 19.0 grains of Lil'Gun.
A good all-around bullet weight is 125 grains, and the three tested performed impressively. The Nosler Ballistic Tip "Hunting" with 17.0 grains of AA-4100 at 2,211 fps would make a dandy deer load, while the Sierra Spitzer liked 18.0 grains of Alliant's new Power Pro 300MP at 2,116 fps. The Speer TNT hollow point propelled by 16.0 grains of AA-9 at 2,099 fps would be coyote poison.
A real sleeper in the hunting-load category is the new Hornady 140-grain MonoFlex, Designed for the .30-30 Winchester, the MonoFlex incorporates Hornady's "Flex Tip" technology into a monolithic, lead-free bullet. The top load with it was 17.0 grains of Lil'Gun for 1,855 fps.
You'd think that traditional 125-, 150- and 170-grain flat-point .30-30 bullets would be perfect for the short COLs required for the .300 Blackout. I tried several, but they were totally unsuitable, as they must be seated so deeply for their flat points to clear those magazine ridges that the resulting rounds are just too short to function. A great idea, but it didn't work.
Velocities of 150-grain hunting bullets topped out at around 1,800-1,900 fps. While they were very accurate, this is about the lower limit for proper expansion downrange, so that may limit their usefulness for hunting.
Paper punchers should try the trio of Sierra MatchKing HPBTs and the Hornady 208-grain A-Max for serious long-range work. All lived up to their reputations for pinpoint accuracy. The Hornady 180-grain SST was very accurate in several loads, and one is shown primarily for reference. Velocity is quite a bit below the minimum 2,400 fps listed in the Hornady "Bullet Guide" in their manual, so expansion would probably be nonexistent. No subsonic loads are listed, as these are primarily for suppressed rifles, and data for such are found in various contemporary manuals.
It's nice to see something "old" become "new," and the .300 Blackout certainly is one of these. Nevertheless, in whatever guise you find it, it's miserly with powder, relatively quiet and highly accurate.
.300 BLACKOUT LOAD DATA BULLET BULLET CASE PRIMER POWDER CHARGE VELOCITY WEIGHT (GR.) (FPS) (CR.) BARNES TSX 110 mil. WSR W-296 20.0 2,369 FB HORNADY V-MAX 110 mil, WSR Viht. 17.0 2,071 N-110 SIERRA HOLLOW 110 mil, CCI-400 H-110 18.5 2,282 POINT NOSLER 125 Hor. AA-1680 20.0 1,946 BALLISTIC CCI-400 TIP NOSLER 125 mil. WSR AA-4100 17.0 2,211 BALLISTIC TIP SPEER TNT HP 125 Hor. CCI-400 A A-9 16.0 2.099 SIERRA 125 mil. WSR Alliant 17.0 2,053 SPITZER SP 2400 SIERRA 125 Hor. CCI-400 PP-300MP 18.0 2,116 SPITZER SP BARNES TSX 130 mil. WSR Lil'Gun 19.0 2,203 BT SIERRA 135 mil. CCI-400 H-110 18.0 2,100 MATCHKING HP BT HORNADY 140 Hor. WSR Lil'Gun 17.0 1,855 MONOFLEX SPEER GRAND 150 mil. CCI-400 PP-300MP 17.0 1,901 SLAM SPEER 150 mil. WSR Lil'Gun 15.5 1,807 MAG-TIP SIERRA PALMA 155 mil. WSR IMR-4227 17.0 1,805 HPBT HORNADY SST 180 Hor. WSR Lil'Gun 15.0 1,720 HORNADY 208 Hor. CCI-400 Viht. 11.0 1,295. A-MAX N-110 BULLET STD. AVG. MUZZLE COL DEV. GROUP ENERGY (IN.) (FPS) (IN.) (FT-LB) BARNES TSX 9 0.67 1,371 2.040 FB HORNADY V-MAX 12 0.75 1,048 2.100 SIERRA HOLLOW 11 0.84 1,272 1.935 POINT NOSLER 13 0.76 1,051 2.050 BALLISTIC TIP NOSLER 16 0.77 1,357 2.050 BALLISTIC TIP SPEER TNT HP 18 0.80 1.223 2,000 SIERRA 15 0.68 1,170 2.000 SPITZER SP SIERRA 16 0.76 1,243 2.000 SPITZER SP BARNES TSX 12 0.77 1,401 2.040 BT SIERRA 15 0.87 1,322 2.020 MATCHKING HP BT HORNADY 14 0.63 1070 1.942 MONOFLEX SPEER GRAND .19 0.75 1,204 2.050 SLAM SPEER 16 0.80 1,088 1.957 MAG-TIP SIERRA PALMA 18 0.78 1,122 2.055 HPBT HORNADY SST 17 0.83 1,183 2.098 HORNADY 16 1.05 775 2.200 A-MAX Notes:A Loki Weapons Systems AR-15 whit a 16-inch Satern barrel with an 8:1 twist was used for all testing. Accuracy is average of at lest two, three-shot groups at 80 yards. Abreviations:mil., re-formed 5.56mm military cases; COL, Cartridge Overall Length; TSX, Triple Shock-X; HPBT, Hollow Point Boat Till; SST, Super Shock-Tipped: BT, Boat Tail; FB, Flat Base; PP, Alliant Power Pro.
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|Title Annotation:||G&A RELOADS|
|Publication:||Guns & Ammo|
|Date:||Dec 21, 2011|
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