Cartridge conversions and rifles cartridge compatabikity

[Coffinmaker]

  H.T. JIM 

Perhaps not "widely."  Perhaps "some" conversions were made by local smiths in 45 Henry Flat.  Not by Colt.  Colt only converted to .38 Colt and .44 colt (centerfire).  The first we see of Colt chambering (that I remember) other than 44 Colt was the Colt Open Top.  The Open Top Chambering was actually intended for Colt's proprietary cartridge, the 45 Stetson, which was basically a 44 Henry Flat with a different head stamp.  Colt did that because the original chambering for the 1866 was the 44 Henry Flat and with Colt and Winchester not being Bosom Buddies, yet the market place clamoring for a companion hand gun to the 1866, Colt responded with the Open Top, hence,  the Colt proprietary (but interchangeable) 44 Stetson.  Such a tangled web business weaves.

I could be all wet as I haven't plunged deeply into this history for a long long time.  But atz as I remember reading it.  And, since the 44 Henry Flat/44 Stetson were such short cartridges, I have always tried to give that historic impression using 44 Russian or C45S or 45 Squirt cartridges.  Fun Stuff.

[Hair Trigger Jim]

O estimable crafter of pine boxes,

It's probably me who's all wet.  Now that I think about it, I don't have any knowledge of Colt factory conversions in the Henry cartridge.  I recall seeing an 1860 that I believe was converted to the Henry, but now that I think about it, I think it must have been a gunsmith special because I believe it required removing the barrel to reload.

Colt did, I understand, produce some SAAs in .44 Henry, but of course those aren't conversions.

Is the .45 Henry Flat different from the .44 Henry Flat?

[Coffinmaker]

Oh Krap 

Type 0.  Corrected it I did.  45 Henry Flat should have (now does) read 44 Henry Flat.

Mumble mumble mumble.

[Griff]

And I must chime in with a correction about the 45 Colt... It's "rim" diameter or thickness has not changed since introduction... what has changed is the addition of an extractor groove.