Just took a look at some of these you mentioned. The model 1
American Derringer.
http://www.amderringer.com/m1.html
Also looked at the lm4. I wondered what ever happened to that
Simmerling. It seems to me though that it wasn't an auto. Something in
the back of my mind saying it is some kind of manual action,
that requires some sort of pump action to cycle it.
http://www.amderringer.com/lms.html
I have got interested in light guns recently after having just
bought a Keltec p3at. I wanted something that was so easy
to carry as to be as near unnoticeable as possible. My
previous light weight has been a Star PD. This is quite a
nice little package. It is actually lighter than many 380
autos, even though its a 45. It weighs 25 oz with empty
magazine. Surprising, it is very comfortable
to shoot. The only thing I have found to fault it, is the safety.
It can dig into your side when worn close in. After getting
this new Keltec, with no manual safety, it got me to thinking,
too bad, Star didn't make the PD with double action and
no manual safety to dig into your side.
http://www.alpharubicon.com/leo/starpdserger.htm
The Keltec is nice shooting also. I had an AMT backup
in 380 for a number of years, and I hated shooting it,
it was so uncomfortable, not that you shoot one of these
types of guns often, but I tried to cycle a box through
it about once a year.
Another thing that comes to mind here is on the Star PD.
As I searched for a picture of it, for this post I came
across references to guys using a shock buff in these
guns. I have never used one, and I am curious, as to
where you would put it. Can some one tell where it
would go, possibly using one of the pictures in the above
link to field stripping, to describe where a shock buff
would go, if a colt 45 type would fit in it somewhere.
Ooooh, look here. A Glock 36 weighs 22 1/2 ounces.
and the Para ordnance p10-45 goes just 19 oz
according to this:
http://www.angelfire.com/art/enchanter/carryguns.html