Hi,
I've been reading the forum for a long time, but I believe this is the first time I've posted. I'm a little surprised that the discussion has not mentioned wound ballistics. From what I've learned, and I'm by no means an expert, the number one thing you are looking for is depth of penetration and number two is permanent cavity. Ideally you should have 18 inches of penetration, but for a self defense round you require at least 12. This is to ensure you hit vitals with your shot.
I've also heard that only 60% to 70% of hollow point bullets expand after impact because they strike bone or get shrouded in clothing. So you want to look at the permanent cavity you attain with an unexpanded round.
What I've been able to see from looking at the available statistics is that there are a number of 9mm rounds that penetrate as well as the .45 but none expand as much, and the majority of the time the .45 slug penetrates further. So wouldn't the logical conclusion be to use a double stack .45?
My personal opinion is to find a gun that suits you and practice until it is an extension of yourself. For example I use an M4 for home defense because I've had extensive training with it. I prefer a 1911 because it's what I grew up shooting and I'm the most proficient with it. When I fire a Glock or double stack 1911's I'm much less accurate due to the wider grip, I tend to pull left for some reason. Anyways, the real key is shot placement and being comfortable with your weapon.
“When a training gun stops firing (due to running out of pellets), the shooter is still in the fight and still trying to shoot his enemy as well as trying to not be hit by him. We see them continue to try to work the trigger for one or two times before there is a realization that there has been a stoppage (malfunction or empty gun).”
I thought that was an interesting comment as well. I hadn't noticed the same thing in my training except at the beginner levels. It may be due to different platforms as well. The majority of the training I have participated in was using either blanks or simmunition and has generally been for m4/m16 series rifles and/or m9 pistols. I'm guessing by “pellets” he's talking about airsoft guns, but I can't be sure and I don't want to pretend to know more than I do.
Also I don't want to make it sound like I'm some high speed CAG operator or anything like that. I've spent some time as an armed guard, and I'm currently in a Support Company for the U.S. Army Special Forces. So I have some experience, but take it with a grain of salt.
P.S. It's good to finally talk to you guys, I really have been just reading for years now.
http://www.firearmstactical.com/ammo_data/45acp.htmhttp://www.firearmstactical.com/ammo_data/9mm.htmhttp://www.firearmstactical.com/pdf/fbi-hwfe.pdf