I went to the range yesterday morning and shot up the last of the 130 TGK bullets with IMR4451 powder.
Shot 6 groups at 2711 fps at the same seating depth as in post #1 and averaged 0.382 with one bad group (probably my fault).
The other 5 groups averaged 0.358.
I also shot groups with 130 gr Tipped Match Kings for comparison also with IMR4451 powder.
Shot 8 groups at 2713 fps at the same seating depth as in post #1 and averaged 0.330 with no diverging groups.
Here is a comparison of the results with all 130 TMKs and 130 TGKs that I shot to date.
Performance Summary 130 gr Tipped Sierra 6.5mm Creedmoor Bullets
Powder ----Bullet ------------------------Avg. # grps Median St Dev
IMR4451 Tipped Match King #7430--- 0.354 --32 ---0.361- 0.049
IMR4350 Tipped Match King #7430--- 0.370 --18--- 0.357- 0.068
RL-17 ----Tipped Match King #7430--- 0.376--- 6--- 0.379- 0.049
All Powders Tipped Match King #7430- 0.361- 56--- 0.362-- 0.055
Powder ----Bullet -------------------------Avg. # grps Median St Dev
IMR4451 Tipped Game Changer #4330 0.379 --14--- 0.401-- 0.079
The TGKs are just slightly less accurate but are very still accurate for a hunting bullet.
I also noted that the POI for the TGK was consistently about 1/4 to 5/16 of an inch to the right of the TMK POI with the same POA.
I hypothesized that this might be the result of the slightly thinner jacket on the TGK interacting with the rifling slightly differently than the heavier jacket on the TMK.
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