I recently posted regarding load development for sako trg 6.5cm. I started at the lowest recommended 36.7 gr and loaded up to 42.4 in 0.3 increments (20 rounds). I finally got out to the range today and had some interesting/surprising results:
1. The velocities ranged from 2385-2747 fps and overall group size was less than an inch and probably closer to 0.75 ( this was a huge shocker since the difference in velocity was about 350 fps. Each shot was on its own separate target so I cant give an accurate measurement with my calipers.
2. I did not see any signs of pressure with any of the loads. I was not expecting to shoot all 20 rounds. I've included pictures of my 20th casing as well as my 1st. There were no appreciable differences. Overall the Lapua brass from the loaded ammo had slightly more resistance when extracting vs the hornady factory ammo, not sure why (or if it was all in my head lol). This was noticed immediately even with the lightest load. However, there was no difference between any of the loaded rounds. (see pics below)
3. I measured each shot with my chronograph and did not really see any that were close enough in velocity to call a node.
On to the data
Round number/ Charge (gr)/ Velocity(fps)
1. 36.7, 2389
2. 37.0, 2385
3. 37.3, 2403
4. 37.6, 2415
5. 37.9, 2427
6. 38.2, 2462
7. 38.5, 2477
8. 38.8, 2489
9. 39.1, 2514
10. 39.4, 2533
11. 39.7 2564
12. 40.0, 2565
13. 40.3, 2588
14. 40.6, 2612
15. 40.9, 2631
16. 41.2, 2662
17. 41.5, 2685
18. 41.8, 2704
19. 42.1, 2734
20. 42.4, 2747
Top left target was factory ammo, I was having a hard time getting my chrono to read, it was my first time using my labradar with a muzzle brake, but once i figured it out it performed flawlessly. Round 1 was shot at the large green and orange target, to be honest i was not sure what to expect with my first ever loaded round so i wanted to make sure I hit the target. I then started on then started my string of shots beginning on the 2nd row. However i realized i only had 15 targets remaining on that specific sheet. I ended up shooting 18-20 on the green and orange target as well. All shots are marked with the corresponding number.
Now for the advice portion... Should continue to increase my charge to figure out what max load is? Or should load in 0.1 gr from 41.8-42.4. 3 rounds of each? This should give me more information on SD and ES. Or is there something i am missing?
Thanks for reading this long post!
The first 2 pictures of brass are the lowest load, the 3rd and 4th picture is the hottest load.
And lastly the targets.
1. The velocities ranged from 2385-2747 fps and overall group size was less than an inch and probably closer to 0.75 ( this was a huge shocker since the difference in velocity was about 350 fps. Each shot was on its own separate target so I cant give an accurate measurement with my calipers.
2. I did not see any signs of pressure with any of the loads. I was not expecting to shoot all 20 rounds. I've included pictures of my 20th casing as well as my 1st. There were no appreciable differences. Overall the Lapua brass from the loaded ammo had slightly more resistance when extracting vs the hornady factory ammo, not sure why (or if it was all in my head lol). This was noticed immediately even with the lightest load. However, there was no difference between any of the loaded rounds. (see pics below)
3. I measured each shot with my chronograph and did not really see any that were close enough in velocity to call a node.
On to the data
Round number/ Charge (gr)/ Velocity(fps)
1. 36.7, 2389
2. 37.0, 2385
3. 37.3, 2403
4. 37.6, 2415
5. 37.9, 2427
6. 38.2, 2462
7. 38.5, 2477
8. 38.8, 2489
9. 39.1, 2514
10. 39.4, 2533
11. 39.7 2564
12. 40.0, 2565
13. 40.3, 2588
14. 40.6, 2612
15. 40.9, 2631
16. 41.2, 2662
17. 41.5, 2685
18. 41.8, 2704
19. 42.1, 2734
20. 42.4, 2747
Top left target was factory ammo, I was having a hard time getting my chrono to read, it was my first time using my labradar with a muzzle brake, but once i figured it out it performed flawlessly. Round 1 was shot at the large green and orange target, to be honest i was not sure what to expect with my first ever loaded round so i wanted to make sure I hit the target. I then started on then started my string of shots beginning on the 2nd row. However i realized i only had 15 targets remaining on that specific sheet. I ended up shooting 18-20 on the green and orange target as well. All shots are marked with the corresponding number.
Now for the advice portion... Should continue to increase my charge to figure out what max load is? Or should load in 0.1 gr from 41.8-42.4. 3 rounds of each? This should give me more information on SD and ES. Or is there something i am missing?
Thanks for reading this long post!
The first 2 pictures of brass are the lowest load, the 3rd and 4th picture is the hottest load.
And lastly the targets.