Wednesday, January 28, 2015

Ballistic Chit Chat....or Anecdotal Evidence, Pt. 2

A while back I posted up some anecdotal terminal ballistics results... found here As mentioned then it is hardly definitive, but rather data for the wider body of knowledge.

The year's results are as follows-

.300 WSM/ 180 Accubond- this load continues to give good results. 2 caribou this year, one at an easy 150yds and the other my longest shot to date- 355 yards. The 150yd shot showed perfect expansion, very few bullet fragments in the wound channel and a large exit wound. Placement was good on the rear of the on side shoulder and it exited the gap of the last two ribs. Death was near instantaneous. The 350yd shots- took two, neither placed perfectly. The first was a bit far back, through the liver. The second through the shoulder blade and spine. Both were solid hits, but not immediately fatal. 350yd. energy figure are down quite a bit but both bullets exited despite some bone  being involved. No fragments were found.

.338WM/ 180 Accubond- this load accounted for two caribou. Both dropped at near 400yds. The light for caliber but tough Accubond in the .338WM has turned in good performance- particularly on light game (for a .338 at any rate) at long range. Good expansion, no fragments and one shot kills. This combination makes the .338WM a very versatile cartridge when compared to what was available in the last couple of decades.

7-08 Rem/ 140gr Fusion- this load out of my son's Savage carbine did not impress. On the first shot at his caribou, the bullet failed to expand much (if any) on a high lung shot. The animal showed little reaction but would have expired after some period. 2nd shot hit a veterbrae, results were instantaneous and would have been so regardless of bullet weight, construction or cartridge. Limited testing showed acceptable accuracy in the rifle- better than a couple of competing brands- but I think the 140r Fusion is a Speer DeepCurl bullet and was designed for 7mm Remington Magnum velocities  and not the milder 7-08 Remington. The Savage's 20" barrel further exacerbates this reducing speeds over a 24" barrel to a degree.

It seems that poor performance on game follows last year's results- simply put, bullets being too hard for impact speeds. This is in stark contrast to previous trends in bullets as too soft for magnum velocities and premature expansion being the rule.  In the 7-08 I will try to find a load with the typical 120gr bullet given how open our usual environment is and the shorter barrel length of the carbine. I'll do tests on the 120gr Ballistic Tip and the TTSX, both at 2950. The BT should open at lower impact speeds while the TTSX will provide greater penetration within our usual ranges.

The "tipped and bonded" bullets seem to produce good results at all ranges to date, with a balance of expansion and penetration.

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