Warning: Math Content!
Maybe this was kind of obvious, but...
I first measured the length (on the picture) that the slide looks like it can move. On my monitor, that turned out to be 17mm.
Since we know that the magazine pictured is the same as the LS mags, I then measured the width of the magazine in the picture: 14.5mm
From that alone, we can see that the length of the plunger draw and that of the LS mag are fairly close. To be more exact, however, we can use the relationship:
Length of slide movement (pic)/length of mag (pic) = length of slide movement (real life)/length of mag (real life)
Unfortunately, I don't know of any LS mags within 45 minutes of me (besides those in stores, of course). So, I can't give you the answer.
However, if someone would kindly measure the length of their LS mag (in inches or millimeters, doesn't matter) then multiply by 17 and divide by 14.5, we'll know the length of the plunger chamber.
Of course, that tells us nothing about the radius of the plunger chamber, but at least it's something.
Edit: Furthermore, to find total length, its the mag length times 122 and divided by 14.5.
Finally, the length of just the pistol (as far as I can tell) is the mag length times 44.5 and divided by 14.5.
Edited by jwasko, 25 October 2007 - 07:14 PM.