Perhaps Cody can comment on the difference on bullet performance, the 156 seemed to be a bit more explosive than the 140
Sure, I have a good amount of data on the 156 on game, I think we're at around 20 critters with them now?
I'll attach some photos, and link the thread on the terminal performance of the 156 I did. Game results start on page 10 -
I have seen similar effects switching to the hotter 450’s, particularly when temperatures are running lower. The thicker cup is also less prone to cratering at the higher pressures. Apologies if it was mentioned in a previous post, but what twist rate are you running? I will be very anxious to...
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Overall, I like the performance of the 156 over the 147 eld-m significantly better, photos and ballistic numbers don't really tell that story well, but the way the animal reacts to impacts. With the 147, animals seemed to run more, or at least cover more ground. With the 156, it hits them hard. Had only two animals I saw hit with the 153 A-Tip, both doe pronghorn, one impact was a solid bone hit, lots of damage, but a FMJ would have come unglued with a hit to the shoulder socket. The other was in the pocket just behind the shoulder, broadside. I will say this is hard for many bullets, there is less than 4" total for the bullet to do its thing, and very little resistance, less hair than a chihuahua, paper thin rib meat, and lungs. The A-tip did not expand, at all, and the lungs were still fully in tact, with a small bruise the size of a nickel around the smaller than pencil hole that the bullet left. I have made this hit many times with Bergers successfully on pronghorn.
The real kicker comes when comparing to the 140 VLD. I have taken or my rifle has been used to take somewhere in the neighborhood of 50+ animals, mostly pronghorn but up to bull elk, with the 140 VLD. They both killed fantastic, however I only ever recovered 1 140 VLD in all those animals, from a 6x6 bull elk shot at 713 yards through the upper shoulder, and the bullet was hanging in the exit hole on a piece of meat. The 156, with around half the animals taken, always exits on pronghorn, but only about half the time on mule deer and elk. Internal damage is always fantastic, and surprisingly not a terrible amount of meat damage when looking at the photos above, but not as many exits. So here is how I look at it.
If white tail, blacktail, pronghorn, pigs, sheep, or smaller mulies are the main target, the 156 is excellent, really hard to beat, and the 6.5x284 is an excellent cartridge choice for it. Big mulies, elk, moose are the main target, look at something bigger than a 6.5, my other gun is a 9.5 lb .338 Norma, for mountain mulies and elk, which are also typically longer range. My 14 lb .260 ai lives in the flatlands for pronghorn, or lowland mulies. This combo makes gives me all the warm and fuzziness a guy could want!