Hunting seasons are winding down and I've had a chance to play around with more home swaged hunting bullets this fall. I carried a 21" Shilen barreled M70 chambered in .400 Whelen for both guiding moose and bear clients and my own deer hunting this fall. Here's a thread over on AccurateReloading with a lot of info and data on the .400.
http://forums.accuratereloading.com/...3/m/7511088471
I only used one load, a 350gr core bonded bullet at 2300MV, made with drawn '06 or 308 brass and tried three types of core material. I started the season with SOWW alloy cores and had an opportunity to shoot at least ten slugs into moose bones and scraps and one 9 1/2' brown bear carcass.
In the moose scraps, the bullets penetrated around 24" and appeared to open quickly, leaving a 3" permanent hole for about 8-10" then closing up to where the bullets were found. The scrap pile was stacked with a scapula about every 10" to help trace the bullets. A lot of scraps went flying when hit by one of these rapidly opening slugs!
When testing bullets in a bear carcass, I use a few angles as standard shots for comparison purposes. One is across the neck with the thought that it would prove whether the load could break a bear's neck and be a viable load for self defense. To put it in perspective, at PBR, a .338WinMag/250gr Partition/2700MV will generally penetrate to the vertebra, break it handily but remain within that area. Most hard cast magnum revolver loads with do the same - 180gr .357s, 240-300gr .44s etc. A 300gr .338 Accubond at 2500 will exit the neck completely. The 350gr .400 managed to penetrate the neck completely, including a good bit of destruction at the vertebra and I luckily found one of the slugs in the dirt on the offside (the other ricocheted away).
Another standard test shot is on the shoulder, trying to hit the humerus and to see if the load will break one major bone structure and carry on into the vitals. Most hard cast magnum pistols are barely capable of this much penetration but the holes are VERY small. The 350gr/400 managed to smash the humerus rather well but once inside the rib cage, it only made it as far as the heart. That did not seem like much penetration.
With these results, it made up some more 350grainers with 12:1 and 20:1 cores with the thought that a harder core might mushroom less. These bullets were test fired into water and used to hunt deer.
The first deer was shot with a SOWW bonded cored and was a good 250-275 yards away. Bullet caught the 175lb buck on one shoulder right at the scapula/humerus joint and exited at the same on the offside. Needless to say, the deer didn't go anywhere. Total penetration was approximately 10" but I was delighted with "baseball" sized areas of destruction on the inside with modest bloodshotting. I was afraid there'd be little left of the shoulders but that wasn't the case.
Second deer, another 175lb buck, was shot with a 12:1 bonded core and was running almost directly away at approximately 150 yards. The bullet caught him in the right hamstring, penetrated forward through the ham, through the paunch, through the liver and was recovered under the skin about 1/3 of the way forward along the left rib cage. The buck did not react to the shot but there was a lot of hair where he was hit and he only made it another 50 yards where he bedded down just inside some timber. He was sick enough to be pretty much down and out but I immediately put a mercy shot into the base of his skull.
The 12:1 core has proved to be disappointing in this deer and also water. Instead of holding together like the SOWW cores, they crumble and even though there's a lead wash bonded to the inside of the peeled back jackets, the core has separated.
Last deer was back to the SOWW cores. This was a 100lb doe that gave me a perfectly straight on frontal shot. The bullet entered her throat, nicking the vertebra on the way in, split all the vessels above the heart, missed the liver but penetrated the stomach and paunch, penetrated the inside top of the left ham and exited just beside her tail! I was hoping to get a lengthwise shot and recover another bullet but not to be. This slug penetrated a good 32-36" and since she was in tall grass, no chance of finding the slug. The deer collapsed to the shot. The same damage evident in the moose scraps occurred in the deer but due to placement, it was all in the chest and I recovered almost 100% of the meat (wonderfully delicious meat!)
So, I'm really liking the weight retention of the SOWW cores and for anything less than bears, they'll give plenty of penetration. To use up and test some random slugs, I shot the remainder into water. It appears that 20:1 is a little better than 12:1 but not quite the answer. I'll try some 30:1 this winter to see if that will reduce the mushroom diameter yet remain ductile enough to retain 90% or better. I've thought of Corbin's "partition" trick of two jackets, one up-side-down in the other but that seems like a lot of work. Any other suggestions are welcome!