An amusing story I'll tell on myself.
I had such an arm, some years back. It was a Winchester model 1892, not a 94, marked something like
P de DSJ (maybe San Juan District Police???) The original 44 WCF marking had been neatly overstamped to 4
5 and I could see how the lifter had a new cartridge stop brazed on, for the shorter cartridge. The finish was rather worn and the wood, though badly scratched up, was sound. But the action locked up like a bank vault and the bore was in nice shape. I picked it up at a Fort Worth Gun Show for what I considered quite a bargain. I stopped on the way home on a country road and fired about ten rounds of mixed .45 ACP ammo into a ditch. Functioning was very good.
It was a couple of weeks before I could take it to the range. I was very disappointed when I couldn't keep it on paper at 50 yards. At 25 yards, I could sometimes hit the target but noticed that half the bullet strikes showed keyholing. Recoil was fairly sharp with standard level handloads and ball ammo. I took casual notice that the primers were somewhat flattened on the brass. While changing targets, I picked up a couple of bullets from the berm and saw that something "looked funny" about them.
At home, it dawned on me that, compared to some other bullets fired through handguns, the rifling marks extended over a greater length than looked proper. The exposed lead at the base appeared to have melted.
When it finally occurred to me to measure the fired bullets, the light finally penetrated my dim brain.
Diameters ran about .428" rather than the expected .452! When the rather neat conversion and rechambering had been done, someone neglected to replace or rebore the barrel to the proper dimensions.
The fact that the nifty little carbine suffered no ill effects was a tribute to the strangth of the '92 action. It did not reflect positively on my own perceptions, though.
With full disclosure, I sold the piece to a gunsmith friend, for a conversion with a new barrel.
I'd imagine that most of the police carbine conversions were fitted with properly bored barrels, but I'd sure suggest careful examination before firing one of them!
Best,
Johnny