goldylocks333
FNG
- Joined
- Jan 10, 2026
- Messages
- 34
Hey guys!
Brand new reloader here. I just worked up my first set of test loads for my .308, and I'm having a hard time making sense of how they shot and could use some wisdom! I worked these up mostly to learn about the process and get experience.
Here's the data on the loads:
Bullet:
Hornady 308 150gr FMJ-BT #3037
BC: .398 (G1)
SD: .226
Powder:
Vihtavuori N150. Their tests with this bullet were from 44.0 gr - 48.0 gr. I tested the following, 5 rounds of each:
46.0gr
46.5gr
47.0gr
47.5gr
48.0gr
Brass: All matching Winchester, once fired. No crimp.
Primer: Magtech Large Rifle.
All bullets were backed off the lands by 0.005."
Shooting was done at 100yrds, and from a vice. Loads were shot out of a 20" barrel with a 1/10 twist.
Here is how they shot:
46.0gr loads:
#1: 2712 FPS
#2: 2708 FPS
#3: ERR
#4: 2738 FPS
#5: 2706 FPS
Avg: 2716 FPS
Min/Max difference: 32 FPS

46.5gr loads:
#1: 2686 FPS
#2: 2755 FPS
#3: ERR
#4: 2718 FPS
#5: 2742 FPS
Avg: 2725 FPS
Min/Max difference: 69 FPS

47.0gr loads:
#1: 2780 FPS
#2: 2789 FPS
#3: 2755 FPS
#4: 2794 FPS
#5: 2761 FPS
Avg: 2776 FPS
Min/Max difference: 39FPS

47.5gr loads:
#1: 2813 FPS
#2: 2831 FPS
#3: 2835 FPS
#4: 2816 FPS
#5: ERR
Avg: 2824 FPS
Min/Max difference: 22FPS

48.0gr loads:
#1: ERR
#2: 2841 FPS
#3: 2839 FPS
#4: 2841 FPS
#5: 2831 FPS
Avg: 2838 FPS
Min/Max difference: 10FPS

For comparison (and to make sure I wasn't the problem), here is a 5 shot group I shot right after these with Factory Hornady Black 168gr.

It looks like the 46.5 and 48.0 shot the best groups, and the 48.0 had the tightest FPS. But no group looks good compared to factory.
My question is where do I go from here? Should I try the same loads with a crimp so they have even neck tension? Go down in powder charge? I know that the projectile isn't the greatest, but should my groups be this bad? I'm here to learn!
Brand new reloader here. I just worked up my first set of test loads for my .308, and I'm having a hard time making sense of how they shot and could use some wisdom! I worked these up mostly to learn about the process and get experience.
Here's the data on the loads:
Bullet:
Hornady 308 150gr FMJ-BT #3037
BC: .398 (G1)
SD: .226
Powder:
Vihtavuori N150. Their tests with this bullet were from 44.0 gr - 48.0 gr. I tested the following, 5 rounds of each:
46.0gr
46.5gr
47.0gr
47.5gr
48.0gr
Brass: All matching Winchester, once fired. No crimp.
Primer: Magtech Large Rifle.
All bullets were backed off the lands by 0.005."
Shooting was done at 100yrds, and from a vice. Loads were shot out of a 20" barrel with a 1/10 twist.
Here is how they shot:
46.0gr loads:
#1: 2712 FPS
#2: 2708 FPS
#3: ERR
#4: 2738 FPS
#5: 2706 FPS
Avg: 2716 FPS
Min/Max difference: 32 FPS

46.5gr loads:
#1: 2686 FPS
#2: 2755 FPS
#3: ERR
#4: 2718 FPS
#5: 2742 FPS
Avg: 2725 FPS
Min/Max difference: 69 FPS

47.0gr loads:
#1: 2780 FPS
#2: 2789 FPS
#3: 2755 FPS
#4: 2794 FPS
#5: 2761 FPS
Avg: 2776 FPS
Min/Max difference: 39FPS

47.5gr loads:
#1: 2813 FPS
#2: 2831 FPS
#3: 2835 FPS
#4: 2816 FPS
#5: ERR
Avg: 2824 FPS
Min/Max difference: 22FPS

48.0gr loads:
#1: ERR
#2: 2841 FPS
#3: 2839 FPS
#4: 2841 FPS
#5: 2831 FPS
Avg: 2838 FPS
Min/Max difference: 10FPS

For comparison (and to make sure I wasn't the problem), here is a 5 shot group I shot right after these with Factory Hornady Black 168gr.

It looks like the 46.5 and 48.0 shot the best groups, and the 48.0 had the tightest FPS. But no group looks good compared to factory.
My question is where do I go from here? Should I try the same loads with a crimp so they have even neck tension? Go down in powder charge? I know that the projectile isn't the greatest, but should my groups be this bad? I'm here to learn!




