I've had a few of the newer Afterburners from Apex in my hands for a while now, but I'm just getting time to start working with them now. I thought I'd post up some of my results as I go along. I have the 102gr 6.5mm, 103gr .277", 117gr 7mm, and 200gr .338" to try out. I'm just starting to work on loads with each bullet, I'll play around with testing expansion later.
102g 6.5mm
I'm going to test these at the low end out of a 6.5 Grendel, and the top end out of a 6.5/338 RUM improved. I just got my first round of testing with the Grendel done today. Here's what I have so far.
6.5 Grendel (CZ 527 with 19" Blackhole barrel, 1:8" twist)
Hornady brass
CCI 450 primer
H335 powder
102gr Apex Afterburner
2.265" OAL
27.4gr - 2408 fps
27.8gr - 2479 fps
28.2gr - 2501 fps
28.6gr - 2561 fps
29.0gr - 2606 fps
29.4gr - 2617 fps
29.8gr - 2670 fps
30.2gr - 2712 fps
I didn't shoot these for groups, just velocity. The 30.2gr charge still didn't show any pressure, so I'll probably try bumping it up a little more. I don't know if I'd go much higher in a gas gun, but I'll push the bolt action a little harder than I would an AR.
103gr .277
I have some of these loaded in a 270/338 RUM improved, but I haven't shot them yet. I expect to be around 4000 fps from a 25" barrel with the 103s. I'm working on getting my hands on a 6.8 SPC to test them at the low-end velocities. I'll add the results for the .270 bullets when I get them.
117gr 7mm
I'll be shooting these in a 19" 284 Win specialty pistol, and a 26" 7mm SAUM. I haven't shot any of the loads in the 7mm SAUM yet, but I have shot them in the 284 Win.
284 Win specialty pistol (18" McGowen barrel, 1:9" twist)
Lapua Brass
CCI 200 primer
Reloader 15.5 powder
117gr Apex Afterburner
2.922" OAL
50.0gr - 2822 fps
50.5gr - 2902 fps
51.0gr - 2940 fps
51.5gr - 2971 fps
52.0gr - 3043 fps
52.5gr - 3060 fps
53.0gr - 3074 fps
53.5gr - 3102 fps
54.0gr - 3145 fps
54.5gr - 3193 fps
The 54.5gr load was just starting to show a drag on bolt lift, so I stopped there. Those loads were all shot at 100 yards and gave a 1"group for all 10 shots fired. I went back out and tested a charge of 54.2gr of Reloader 15.5 with the 117gr Afterburner at 3165 fps and shot a few groups withouth the Magneto strapped to the barrel. The result was 3 separate 3 shot groups right at .5 MOA at 215 yards, which is about what I've come to expect with this barrel these days. For reference, my standard load in this gun for years has been a 168gr Berger VLD at 2670 fps. It has typically shot better with pretty moderate loads. I'll head out again and try shooting at 500+ yards on the next trip out.
200gr .338
The goal is to test these in a 338/375 Ruger specialty pistol for the low end and a 338/408 Improved speciatly pistol for the high end velocities. I have a 338 Win Mag rifle sitting around too, but those velocities will be very similar to the velocities from the 18" 338/375 Ruger specialty pistol. I've run the first ladder in the 338/375 already, but haven't had time to go for a second trip out with them. For reference, the case capacity of the 338/375 Ruger is in the same range as the 340 Weatherby, 33 Nosler, and 330 Dakota. This data might be helpful for anyone shooting one of those.
338/375 Ruger specialty pistol (18" Benchmark barrel 1:9.3" twist)
Hornady brass (375 Ruger necked down)
Fed 215 primers
Reloader 15.5 powder
3.415" OAL
70.0gr - 2735 fps
71.0gr - 2765 fps
72.0gr - 2833 fps
73.0gr - 2904 fps
73.5gr - 2905 fps
74.0gr - 2916 fps
74.5gr - 2970 fps
75.0gr - 2984 fps
I was hoping to get 2950 fps with the 200gr Afterburner, so I'm happy with the velocities I saw. There were no pressure signs, so I'll try loading a few more at a higher charge for the next trip out. If I can get .5 MOA accuracy at 2975-3000 fps, I'd be extremely happy. My standard target load in this gun is a 250gr SMK at 2645 from the 18" barrel, and the hunting load has been a 260gr HH at 2660 fps for a few years. Gaining 300 fps by dropping 50gr of bullet weight makes a pretty big difference. This is my mid-long range (400-750 yard) hunting pistol, so velocity and BC are both a consideration with this gun.
I'll update this thread as I get more shooting done. I'm just starting to slow down at work so I have more time, but now I'm at the mercy of the weather.
102g 6.5mm
I'm going to test these at the low end out of a 6.5 Grendel, and the top end out of a 6.5/338 RUM improved. I just got my first round of testing with the Grendel done today. Here's what I have so far.
6.5 Grendel (CZ 527 with 19" Blackhole barrel, 1:8" twist)
Hornady brass
CCI 450 primer
H335 powder
102gr Apex Afterburner
2.265" OAL
27.4gr - 2408 fps
27.8gr - 2479 fps
28.2gr - 2501 fps
28.6gr - 2561 fps
29.0gr - 2606 fps
29.4gr - 2617 fps
29.8gr - 2670 fps
30.2gr - 2712 fps
I didn't shoot these for groups, just velocity. The 30.2gr charge still didn't show any pressure, so I'll probably try bumping it up a little more. I don't know if I'd go much higher in a gas gun, but I'll push the bolt action a little harder than I would an AR.
103gr .277
I have some of these loaded in a 270/338 RUM improved, but I haven't shot them yet. I expect to be around 4000 fps from a 25" barrel with the 103s. I'm working on getting my hands on a 6.8 SPC to test them at the low-end velocities. I'll add the results for the .270 bullets when I get them.
117gr 7mm
I'll be shooting these in a 19" 284 Win specialty pistol, and a 26" 7mm SAUM. I haven't shot any of the loads in the 7mm SAUM yet, but I have shot them in the 284 Win.
284 Win specialty pistol (18" McGowen barrel, 1:9" twist)
Lapua Brass
CCI 200 primer
Reloader 15.5 powder
117gr Apex Afterburner
2.922" OAL
50.0gr - 2822 fps
50.5gr - 2902 fps
51.0gr - 2940 fps
51.5gr - 2971 fps
52.0gr - 3043 fps
52.5gr - 3060 fps
53.0gr - 3074 fps
53.5gr - 3102 fps
54.0gr - 3145 fps
54.5gr - 3193 fps
The 54.5gr load was just starting to show a drag on bolt lift, so I stopped there. Those loads were all shot at 100 yards and gave a 1"group for all 10 shots fired. I went back out and tested a charge of 54.2gr of Reloader 15.5 with the 117gr Afterburner at 3165 fps and shot a few groups withouth the Magneto strapped to the barrel. The result was 3 separate 3 shot groups right at .5 MOA at 215 yards, which is about what I've come to expect with this barrel these days. For reference, my standard load in this gun for years has been a 168gr Berger VLD at 2670 fps. It has typically shot better with pretty moderate loads. I'll head out again and try shooting at 500+ yards on the next trip out.
200gr .338
The goal is to test these in a 338/375 Ruger specialty pistol for the low end and a 338/408 Improved speciatly pistol for the high end velocities. I have a 338 Win Mag rifle sitting around too, but those velocities will be very similar to the velocities from the 18" 338/375 Ruger specialty pistol. I've run the first ladder in the 338/375 already, but haven't had time to go for a second trip out with them. For reference, the case capacity of the 338/375 Ruger is in the same range as the 340 Weatherby, 33 Nosler, and 330 Dakota. This data might be helpful for anyone shooting one of those.
338/375 Ruger specialty pistol (18" Benchmark barrel 1:9.3" twist)
Hornady brass (375 Ruger necked down)
Fed 215 primers
Reloader 15.5 powder
3.415" OAL
70.0gr - 2735 fps
71.0gr - 2765 fps
72.0gr - 2833 fps
73.0gr - 2904 fps
73.5gr - 2905 fps
74.0gr - 2916 fps
74.5gr - 2970 fps
75.0gr - 2984 fps
I was hoping to get 2950 fps with the 200gr Afterburner, so I'm happy with the velocities I saw. There were no pressure signs, so I'll try loading a few more at a higher charge for the next trip out. If I can get .5 MOA accuracy at 2975-3000 fps, I'd be extremely happy. My standard target load in this gun is a 250gr SMK at 2645 from the 18" barrel, and the hunting load has been a 260gr HH at 2660 fps for a few years. Gaining 300 fps by dropping 50gr of bullet weight makes a pretty big difference. This is my mid-long range (400-750 yard) hunting pistol, so velocity and BC are both a consideration with this gun.
I'll update this thread as I get more shooting done. I'm just starting to slow down at work so I have more time, but now I'm at the mercy of the weather.
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