It is no secret I prefer the 6.5 Grendel to all other intermediate calibers in the AR-15 platform, but I lusted after the 300 Blackout since it was the 300 Whisper. I was a wee lad playing Rainbow Six and couldn't afford the freight JD Jones demanded, but I ran wild with a virtual Whisper.
When AAC announced the 300 Blackout, I was an early adopter - I immediately bought a 9" AR and 16" Model 7. When the twist rate sped up, I sold the 9" and bought a 12.5" AAC MPW and began the stupidly expensive process of SBR'ing and stripping down and re-imagining the Model 7. It now has a 12.5" Krieger barrel with a 1:7.5" twist, sits in a Bell & Carlson Youth Medalist, has mag fed bottom metal and a Jewell trigger with a Leupold VX-R 3-9x40 on top. It was not a straight line to that end result - but, I've ended up with a laser beam of a kids rifle, and my sons love it.
The 12.5" MPW was my go-to pig killer for years. I used Barnes 110 gr Tac XT copper black tip to decent effect, but Clint Smith told me on the front end - hits like the kitchen sink up close, has a rainbow trajectory and is lacking at the pot of gold end. Once I transitioned to the 6.5 Grendel, I never seriously picked up the 300 Blackout again.
And den... recently I heard someone speaking of newer, hotter 300 BO ammo, specifically the Blackarc Munitions 110 Gr Tac XT. It was said to make 2300 out of a 10.x" barrel, which got my attention as that led me to think it would likely be 100-150 fps faster than my previous ammo, and I'm thrilled to say I was correct. Some research led me to also pick up the Hornady 110 gr V-Max. Today, I got them out to the range and I feel like my 300's have a new lease on life.
Barrels are weird. My AAC has a 12.5", my Model 7 has a 12.5" - The AAC shot the Blackarc as fast as 2,370 FPS, but the Hornady wouldn't crack 2,340. The Model 7 wouldn't get past 2,320 with the Blackarc, but got as hot as 2,380 with the Hornady.

Lil Wayne told us it would all work out, and it did, because the Blackarc shot exceptionally well out of the MPW and the Hornady was a laser beam out of the Model 7. Using an ACOG with 4x and no eye box isn't exactly a precision circumstance - but - the attached photos were both shot at 100 yards, and it makes me think it would be a sub MOA situation with a 20X scope as opposed to an ACOG where I was just trying to hold steady on an geometric shape and keep the cross evenly distributed. The Model 7, with the benefit of a Krieger and 9X magnification was same holing at 100.
TLDR - Blackarc and Hornady are making 300 Blackout 110 gr ammo that are knocking on 2,400 fps out of 12.5" barrels and shooting very straight in the process. I am going to leave the Grendel at the house next we chase pigs in the brush, and look forward to my youngest getting a white tail with the Model 7 this fall. This ammo is appreciably faster than what I've tried before by 100-150 FPS.
In other wonderfully serendipitous news, the velocity Blackarc delivers means it is as good as real world gets when it comes to matching up with a 300 BO ACOG. I shot the MPW back to 400 yards today - velocity is about 1,370 fps at 400 yards, expansion threshold is 1,350 - elevation was dead on at 200, 300, and 400 and group sizes range from excellent to sufficient.
When AAC announced the 300 Blackout, I was an early adopter - I immediately bought a 9" AR and 16" Model 7. When the twist rate sped up, I sold the 9" and bought a 12.5" AAC MPW and began the stupidly expensive process of SBR'ing and stripping down and re-imagining the Model 7. It now has a 12.5" Krieger barrel with a 1:7.5" twist, sits in a Bell & Carlson Youth Medalist, has mag fed bottom metal and a Jewell trigger with a Leupold VX-R 3-9x40 on top. It was not a straight line to that end result - but, I've ended up with a laser beam of a kids rifle, and my sons love it.
The 12.5" MPW was my go-to pig killer for years. I used Barnes 110 gr Tac XT copper black tip to decent effect, but Clint Smith told me on the front end - hits like the kitchen sink up close, has a rainbow trajectory and is lacking at the pot of gold end. Once I transitioned to the 6.5 Grendel, I never seriously picked up the 300 Blackout again.
And den... recently I heard someone speaking of newer, hotter 300 BO ammo, specifically the Blackarc Munitions 110 Gr Tac XT. It was said to make 2300 out of a 10.x" barrel, which got my attention as that led me to think it would likely be 100-150 fps faster than my previous ammo, and I'm thrilled to say I was correct. Some research led me to also pick up the Hornady 110 gr V-Max. Today, I got them out to the range and I feel like my 300's have a new lease on life.
Barrels are weird. My AAC has a 12.5", my Model 7 has a 12.5" - The AAC shot the Blackarc as fast as 2,370 FPS, but the Hornady wouldn't crack 2,340. The Model 7 wouldn't get past 2,320 with the Blackarc, but got as hot as 2,380 with the Hornady.

Lil Wayne told us it would all work out, and it did, because the Blackarc shot exceptionally well out of the MPW and the Hornady was a laser beam out of the Model 7. Using an ACOG with 4x and no eye box isn't exactly a precision circumstance - but - the attached photos were both shot at 100 yards, and it makes me think it would be a sub MOA situation with a 20X scope as opposed to an ACOG where I was just trying to hold steady on an geometric shape and keep the cross evenly distributed. The Model 7, with the benefit of a Krieger and 9X magnification was same holing at 100.
TLDR - Blackarc and Hornady are making 300 Blackout 110 gr ammo that are knocking on 2,400 fps out of 12.5" barrels and shooting very straight in the process. I am going to leave the Grendel at the house next we chase pigs in the brush, and look forward to my youngest getting a white tail with the Model 7 this fall. This ammo is appreciably faster than what I've tried before by 100-150 FPS.
In other wonderfully serendipitous news, the velocity Blackarc delivers means it is as good as real world gets when it comes to matching up with a 300 BO ACOG. I shot the MPW back to 400 yards today - velocity is about 1,370 fps at 400 yards, expansion threshold is 1,350 - elevation was dead on at 200, 300, and 400 and group sizes range from excellent to sufficient.
Attachments
-
20250813_103105.jpg74.8 KB · Views: 23
-
Chart.png29.5 KB · Views: 23
-
ACOG subtension.png24.8 KB · Views: 22
-
20250813_120639.jpg58.7 KB · Views: 21
-
20250813_120457.jpg104.4 KB · Views: 22
-
20250813_115148.jpg135.7 KB · Views: 25
-
20250813_112445.jpg172.9 KB · Views: 26
-
20250813_112426.jpg112.1 KB · Views: 26
-
20250813_103822.jpg78.9 KB · Views: 23
Last edited: