[Qwiks draw]

Glasers and Magsafes will penetrate clothing (includes heavy clothing) before dumping it's load.
Couple of caveats though. Being very light bullets these will hit very low on a target. Not written in stone, but many have been known to hit from about 6 inches to lower on a target. Have to shoot a few to see where actual POI is and make adjustments to raise the sights so POI hits dead center. These loads did hit low in .38 Special for me.Taurus model 66 and the 2.5 inch barreled guns were what is used.

Very heavy winter clothing will reduce the penetration available. Will use the Glasers in the revolvers (.357 magnum/.38 Special) in during the warm months of the year.

Auto pistol rounds for any frangible defense load may or may not cycle the slide properly or consistently. So like any defense round a decent number of rounds has to be tried for to check for proper function. Not just a few rounds either. Expensive in some ways, but one's betting one's life or or other's that the round will function everytime otherwise.
This is a case by case basis for each pistol, pistol brand,make, and model.

This has been documented by the police trainers and gun gurus who do the actual teaching and have real world experience with this.

I have several the 9mm. Glasers first up the spout on my Ruger 95s and JHPs after that. All work together.

I do not use +P normally in the 9mm. PT111 Mil/pro. This due to battering the gun,little velocity gain, and there are 9mm. +P loads that the velocity, bullt weight, or pressures that may be to great for the small framed pistol.

Glasers, Magsafes, and other frangible defense rounds do have a place in the niche as others have stated above.

One last thing. This may have been noted already. Glaser Silver will penetrate deeper than the Blue nosed versions. The wounds are not as dynamic as width wise for Silver as for the Blue versions. Not written in stone though. But the wound width is still large and deeper than for Blued versions.

There are good reasons for having one or both types of Glaser.

 

[Qwiks draw]

Glasers and other defence loads of similar ilk all have a place in the great scheme of things.

These were developed mostly for the Sky Marshalls on commercial aircraft. Overpenetrative regular JHPs roundnose, or hardball just won't get the job done safely in the confined spaces of a airliner as will Glasers and their kin.
This for safety of others at all levels for a whole lot of good reasons.

Pentration regardless of the test media used, does not begin to simulate flesh and bone. Granted some testing is needed for obvious reasons.

Will get back to that in a minute.

Safety covers many different aspects. Most of all it covers "collatoral damage".

The fragmented rounds will not put at risk life and limb of unintended targets through ricochet of the round or overpenetration of an assailant.
One other factor. These loads dump their entire payload into the assailant. This being kinetic energy and the payload of shot. These were designed to cause major trauma to organs and flesh. They do that as designed. Most of the time that is.

Very soft tissue or the neck hits have not at times dumped the payload as advertised. Granted.
Safety also alludes to the fact that if the trauma is suffered then the assailant need not be shot excessively. Thus multiple wounds( trauma surgeons claim that gunshot wounds,even round nosed ones are most hard to repair) do not need be repaired sparing the person shot and making recovery more likely.
Penetration on most subjects shot has been over 4 inches. Been documented folks. Police and tactical journals.
Oh yes, Glasers and their kin were designed for full frontal torso shots. Happens for civilains close up more so than for LEOs. Granted this situation does not always present itself.

The average male torso (larger than 5'9'tall) is a little over 9 inches through and through.Granted there are exceptions.
In several well documented cases (read that as Mas Ayoob,Marshall& Sanow, Dr.Topper, Chuck Karwan) overly obese assailant hits took place. One shot mind you. Attackers took one look at the fact they were bleeding very heavily, sat down due to shock and the fact they had been shot, and desisted from more mayhem. Some of the shot asked not to be shot again. Granted this might not happen in every case. But can you say that is also true for any handgun bullet. Magic bullet, please? There are none. Placement is the major key.

If one has a residence that is of mostly sheetrock walls or has others inside the residence, then having something that does not overpenetrate(JHPs and hardball can and will) the assailant or assailants is an excellent idea. Glasers and their kin disintegrate on hitting thin walls or major obstacles. Less chance of major trauma over that caused by an intact bullet.

Since these close encounters are more the norm for inside buildings this just makes some sense.

Glasers are not magic bullets. There are none. If used for within the parameters that they were designed for Glasers and their kin will do the job.

Will use Glaser inside dwellings and do. Won't use them much outside of that where long shots may take place.
So they have a niche. Narrow, but it is there and has to be considered.

 

[Qwiks draw]

Needed doing. There are lots who have no idea of the how or why of these. Thought putting out some info might be of use.
First Glasers had a liquid base along with the payload for suspension reasons. Or so it was thought it ws needed. The load was re-engineered to take out the liquid and make it a dry load.

Then there were bullet stability problems in the smaller calibers. That was addressed way back when.

Then the company made them " more user friendly" in pistols because of feed issues. The ogive needed more rounding and slimming.

All that's been taken care of down through the years.

One caveat. A goodly number shoud be fired or tried out to see if they feed through the action. Fire and function of the pistol are critical obviously.

Just that feed reliability is a case by case basis for each gun. This is true for any ammo.

 

[Qwiks draw]

Just added that as there are those who assume anything will feed through any action. 'I bought it brand new and it should do what I expect it too' is the mantra of some.
Granted it might get a bit expensive, but it's worth it IMHO.