Barth, you have to consider a few things. It's more than just the size of the shot used. It's the fact that it's encased in a copper jacket to hold it together for penetration and the fact that it's moving at Three Thousand Feet Per Second when it hits and fragments.
Look, the whole point of a fragmenting round is NOT to penetrate. You can't very well make a logical argument that this round is optimum because it won't overpenetrate drywall but will penetrate adequately in a human body. It makes no sense.
3,000fps isn't going to help once the load is no longer compressed and consists only of individual #12 shot. And exactly where does the Glaser break up and release its shot load? At much lower handgun velocities, the x-ray above shows that it appears to do so immediately upon contact. I don't see much in the way of extra penetration provided by a compressed mass in a copper jacket. In fact, if you'll follow the link to see a picture of the victim you will note two things:
A) The victim is moving under his own power well enough to pose for a picture
B) The initial entry wound shows the shot has already opened up before it has even begun penetrating the skin.
Remember the basic concept of physics that the more mass an object has, the harder it is to accelerate or decelerate that object? This same phenomenon explains why heavier, slower bullets penetrate more deeply than faster, lighter bullets in many scenarios.
Your shotgun full of birdshot ain't doing that. And we're not talking Glaser out of a handgun here, we're talking about an aught-six. Unless you live in the Clampett's masion all of your in the same room shots will be less than 20 feet.
The shotgun full of #6 birdshot is ~1oz of shot (438.75 grains) traveling at 1,300fps from the muzzle (and still mostly compressed by the shot wad at 20'). The .30-06 Glaser is 130gr of #12 shot (1/3 the weight of smaller mass pellets) traveling at 3 times the speed.
Look at the example I showed regarding an arm intervening. What is going to happen in that scenario regardless of whether you use a handgun or rifle Glaser? The shot will break up out of its compressed mass into individual pellets of #12 shot - it will then have to exit the opposite side of the arm (which is very elastic and can use up the same amount of energy as penetrating 4" of gelatin according to researchers in terminal ballistics). It must then penetrate the skin of the torso and continue on deep enough to cause serious blood loss or hit the central nervous system. You are telling me that this will happen with the .30-06 Glaser?
A 130gr Glaser round does not carry that much more shot than a handgun round (80gr for 9mm) and the extra velocity is meaningless because once the slug fragments it will bleed off because a small mass decelerates very quickly.
It's obvious you have NO first hand experience with Glaser rifle ammo. You're just speculating.
I do have firsthand experience with the Glaser .223 rifle ammo. I have never used the .30-06 ammo; but I'd be surprised to find that it both substantially improves the performance of the .223 in penetration and alters the laws of physics regarding the tendency of objects with little mass to quickly accelerate and decelerate. In fact, if you'd like to read my experiences with Glasers (and my former defense of them), you can find them archived at TFL.
If you have some first hand experience with .30-06 Glaser that is relevant, I'd be interested in seeing it presented.
And the original question was what the best ammo for the gun he already has. And I not so humbly gave the best answer based on his criteria.
His criteria was that he wanted something that would not exit the target and present an overpenetration risk. The round you gave him certainly meets that criteria; but I think that your recommendation sacrifices too much performance on the target to meet the goal of reduced penetration.
That's a face full of gas, which can be hard on the eyebones...
