1984dog
Active Member
I spent some range time yesterday with a chronograph. Here are some of my observations from shooting sabots:
1) My first shot with a clean barrel was always a little high. My ML likes a slightly dirty barrel for best accuracy.
2) I used a bore snake twice after each shot and after 3 shots, the muzzle velocity would drop >260 ft/sec. I have always attributed bad groups to a warm/hot barrel but now I know it is the plastic fouling of the rifling that adversely impacts accuracy and velocity. After an aggressive barrel clean, muzzle velocity went back to normal.
Using a Hornady SST 300g, my velocities were: 1757, 1702, 1697, 1489 - clean barrel - 1846 and then 1474. Maybe a different sabot will help.
I've been trying to tie down the load that works best in my ML. I have found that the Hornady Bore Driver and the Hornady Bore Driver ELD-X was the most accurate with the most consistent muzzle velocities. Neither of these use a full sabot but have a unique plastic base. Here are the chronograph results:
Hornady Bord Driver (290 g) 1777, 1820, 1846, 1830 - this is the bullet with the best grouping at 100 yds. ~ 1.2" group
Hornady Bore Driver ELD-X (340 g). This is a big bullet with a boat-tail design. The bullet coefficient is 0.315. Muzzle velocities were: 1704, 1762, 1770, 1778, and 1805. ~2" group. Without the first shot and one flier, I had 3 bullets within 1"
The Hornady Bore Driver (290 g) was the top performer and would be my choice for shots under 125 yards. The ELD-X (340 g) was just a tad slower (and more recoil) but it actually shoots flatter with more energy. If you have shots greater than 125 yds, this would be my choice.
1) My first shot with a clean barrel was always a little high. My ML likes a slightly dirty barrel for best accuracy.
2) I used a bore snake twice after each shot and after 3 shots, the muzzle velocity would drop >260 ft/sec. I have always attributed bad groups to a warm/hot barrel but now I know it is the plastic fouling of the rifling that adversely impacts accuracy and velocity. After an aggressive barrel clean, muzzle velocity went back to normal.
Using a Hornady SST 300g, my velocities were: 1757, 1702, 1697, 1489 - clean barrel - 1846 and then 1474. Maybe a different sabot will help.
I've been trying to tie down the load that works best in my ML. I have found that the Hornady Bore Driver and the Hornady Bore Driver ELD-X was the most accurate with the most consistent muzzle velocities. Neither of these use a full sabot but have a unique plastic base. Here are the chronograph results:
Hornady Bord Driver (290 g) 1777, 1820, 1846, 1830 - this is the bullet with the best grouping at 100 yds. ~ 1.2" group
Hornady Bore Driver ELD-X (340 g). This is a big bullet with a boat-tail design. The bullet coefficient is 0.315. Muzzle velocities were: 1704, 1762, 1770, 1778, and 1805. ~2" group. Without the first shot and one flier, I had 3 bullets within 1"
The Hornady Bore Driver (290 g) was the top performer and would be my choice for shots under 125 yards. The ELD-X (340 g) was just a tad slower (and more recoil) but it actually shoots flatter with more energy. If you have shots greater than 125 yds, this would be my choice.
