Wow, that is penetration.
I am a hoarder of the early Colt autos. Personally inspected hundreds of the 38acp 1900, 1902 Sporting, 1902 Mil, and 1903 Pckt hammer and have fired all but a few of my many 38acp's. I have NEVER seen a stress fracture in the 38acp. I'm sure it has happened, and I would guess that some pistols have been destroyed because of this ( however that is just my guess). Still, I would never shoot 38 super ammo in my old Colt's.
As far as the 1905 45 is concerned, just as previously mentioned, I own a few have had the stress fracture in the front of the slide. My repairs have looked awful. My friend and I tried anther repair that looked better, but would not take a chemical bluing - so it still looks bad. My guess is that large quantaties of military 230 gr hardball went trough many of these 1905's and/or the spring weakened or is to week for this ammo.
As far as the slide coming off while shooting, I've put thousands of rounds through my early autos and will continue to. Never actually seen it happen. Just like my fishing club, without a picture and witness it doesn't count. Not saying that it didn't happen!
Indeed - with the m1905 Colt .45 Automatic, it's appropriate original Ammunition was some ways less powerful than the later Model "O" Ammunition.
I doubt that hardly anyone ever bothered to insist to stay with the proper Ammunition, for their '05, once the Model "O" came out along with it's Ammunition, as the decades wore on.
Nor have I ever seen any Boxes of early .45 ACP, which seemed to represent in the Label, which .45 Auto they were for, other than, when stating Bullet Weight and FPS, they were for the Model "O".
And or that I think far more people were or remained cognizant, of the Ammunition distinction, of .38 ACP and .38 Super.
I have only seen one or maybe two small 'cracks' on the front of the Slide, forward of the Key, on .38 Automatics.
What I have seen far more of, is Bulged Barrels!
One 'Antique Arms Show' I remember, I saw five Bulged Barrel Colt .38 Automatics...which were being offered for sale by three different Sellers.
Sellers had not noticed this, and, had not removed the Slides to notice it.
When feeling interested to maybe buy a .38 Automatic, I would want to field strip, and inspect, which, in each instance I did with the Seller's permission, and, Lo and Behold, "Bulged Barrels".
I imagine this had resulted from 'squib' Loads, long ago, which got the next round firedon top of the lodged Bullet, without clearing the Barrel.