Colt C&B Transitions

[rodwhaincamo]

I'm considering between the Walker and a model (most likely the 2nd as I kind of like the squared trigger guard) of a Dragoon, and am curious about the modifications Colt had made.

Why were the cylinder notches changed from oval to rectangular?
Why change froma V-shaped mainspring to a leaf?
Why was a wheel added to the rear of the hammer?
Why was the trigger guard rounded?
The pins between the nipples are places to safely rest the hammer?
Thanks

 

[rodwhaincamo]

Oops!

 

[Fingers McGee]

I do not know exactly why the changes took place; but can speculate:
Why were the cylinder notches changed from oval to rectangular?
Easier to machine than round/oval stops; rectangle with lead offered more positive lockup and lessened chance of over-rotation or peening of the stop
Why change froma V-shaped mainspring to a leaf?
Easier/cost less to manufcture flat leaf vs V shaped. Leaf easier to replace than V type
Why was a wheel added to the rear of the hammer?
smooth the action/reduce friction
Why was the trigger guard rounded?
square back had tendency to rap knuckles when firing the gun
The pins between the nipples are places to safely rest the hammer?
Correct