Lots of cartridges are interchangeable. Here's one list of them. I take no responsibilty for this information, but since it was on the net, it must be true... right?
FROM
http://yarchive.net/gun/ammo/cartridge_interchange.html
BEGIN QUOTE....
CARTRIDGE INTERCHANGEABILITY CHART
------------------------------------
Cartridges within the groups shown are interchangeable. Other
substitutions should not be made without specific recommendation
of the firearms manufacturer, since improper combinations could
result in firearm damage or personal injury.
-----------------------------------------------------------------
RIMFIRE
22 W.R.F.
22 Remington Special
22 Win. Model 2890 in a 22 Win. Mag Rimfire but not conversely
-----------------------------------------------------------------
CENTERFIRE
25-20 Remington
25-20 W.C.F.
25-20 Win.
25-20 Win. High Speed
25-20 Marlin
25 W.C.F.
-----------------------------------------------------------------
6mm Rem. (80 & 90 grain)
244 Rem.
-----------------------------------------------------------------
25 Automatic
25 Auto. Colt Pistol (ACP)
25 (6.35mm) Automatic Pistol
6.35 Browning
-----------------------------------------------------------------
7mm Express (TM) Rem.
280 Rem.
-----------------------------------------------------------------
30-30 Sav.
30-30 Win.
30-30 Win. Accelerator*
30-30 Marlin
30-30 Win. High Speed
30 W.C.F
-----------------------------------------------------------------
32 Colt Automatic
32 Automatic Colt Pistol (ACP)
32 (7.65mm) Automatic Pistol
7.65mm Automatic Pistol
7.65mm Browning (not interchangeable with 7.65mm Luger)
-----------------------------------------------------------------
32 Short Colt in 32 Long Colt but not conversely
SEE NOTE C
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32 S. & W. in 32 S. & W. Long but not conversely
-----------------------------------------------------------------
32 S. & W. Long
32 Colt New Police
32 Colt Police Positive
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32 W.C.F.*
32 Win.*
32-20 Win. High Speed*
SEE NOTE A
-----------------------------------------------------------------
32-20 Colt L.M.R.
32-20 W.C.F.
32-20 Win. and Marlin
SEE NOTE G
-----------------------------------------------------------------
38 S. & W.
38 Colt New Police
380 Webley
-----------------------------------------------------------------
38 Colt Special
38 S. & W. Special
38 Targetmaster (R)
38 S. & W. Special Mid-Rage
38 Special (+P)
38-44 Special (+P)
38 Special
38 Special Flat Point
SEE NOTES B & D
-----------------------------------------------------------------
38 Short Colt in 38 Long Colt but not conversely;
Both can be used in 38 Special
-----------------------------------------------------------------
38 Marlin
38 Win.*
SEE NOTE A
-----------------------------------------------------------------
38 Remington*
38-40 Win.
38 W.C.F.*
SEE NOTE A
-----------------------------------------------------------------
38 Automatic in 38 Super (+P) but not conversely
-----------------------------------------------------------------
380 Automatic
9mm Browning Short (Corto, Kurz)
-----------------------------------------------------------------
9mm Luger
9mm Parabellum
SEE NOTE E
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44 S. & W. Special
SEE NOTE F
-----------------------------------------------------------------
44 Marlin
44 Win.
44 Remington
44-40 Win.
44 W.C.F.
-----------------------------------------------------------------
45-70 Government
45-70 Marlin
45-70 Win.
45-70-405
-----------------------------------------------------------------
NOTE A: *High-speed cartridges must not be used in revolvers.
They should be used only in rifles made expecially for
them.
NOTE B: Ammunition with (+P) on the case headstamp is loaded to
higher pressure. Use only in firearms designated for
this cartridge and so recommended by the gun manufacturer.
NOTE C: Not for use in revolvers chambered for 32 S. & W. or
32 S. & W. Long.
NOTE D: All 38 Special cartridges can be used in 357 Magnum
revolvers but not conversely.
NOTE E: 9mm sub-machine gun cartridges should not be used in
handguns.
NOTE F: 44 Russian and 44 S. & W. Special can be used in 44
Remington Magnum revolvers but not conversely.
NOTE G: Not to be used in Win. M-66 and M-73.
-----------------------------------------------------------------
SOURCE: 1993 Remington Products Catalog
Not listed in Remington's information are the following:
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.38 Special and .357 Mag. in .357 Maximum, but not conversely
-----------------------------------------------------------------
.44 Special and .44 Mag. in .445 Super Mag, but not conversely
-----------------------------------------------------------------
.45 Long Colt in .454 Casull, but not conversely
-----------------------------------------------------------------
Also, there are many examples of cartridges that can be "fire-
formed" in larger chambers (eg. firing a .300 H&H in a .300 Wby)
but I'll leave off here for now.
. . . . . . . . .
Randy Lyman
[email protected]
END QUOTE (Just trying to preserve the preservie tabbing in the above chart)
Hatcher also has some anecdotal remarks in "Hatcher's Notebook" regarding this.
For instance, some auto cartridges will fire in other auto guns but not vice-versa. I believe he said that .45 ACP will feed from the mag and function, and fire normally in a .455 Webley auto, but not the other way around. This, if I recall correctly, was only true if the rounds were fed from the magazine. It would not work if the cartridges were single loaded, since the cartridge would not engage the extractor hook unless the round came up from the magazine.
I myself have fired 9mm Luger cartridges in a .357 revolver, but I had to tip the gun upward to assure the cartridge was sitting against the recoil shield.
I have also fired .308 Win cartridges in a .30-06 rifle with no ill effects except really crappy accuracy.
Ditto with .22LR in a .22 Mag rifle.
I have done other experiments which are not recommended, but these were when I was young and foolish. As opposed to now, when I am old and foolish.
But I
did get old, despite some hairy experiments.