this probably belongs in the build it yourself section, but the G.D. board gets read much more frequently so:

I have a Chipmunk rifle that my (soon to be) 6 year old daughter will get for her birthday.  I will teach her to shoot with it.  I will also be shooting at the same time with some centerfire rifles.

If (and I don't doubt she will) she eventually wants to shoot a "big person's" gun--

How should it be configured to make it easy for a sub 50 lb child to shoot?

It would pretty much have to configured as a post-ban with a muzzle brake.  So, that leads to these questions--

If I use a pre-ban, I can use a collapsable stock, or a post ban, fixed postion (shortest setting) "collapsable" stock.

Where can I save weight?  

What is the lightest barrel and/or complete upper to use?

Thanks for any pointers.

AFARR

Go for the pre-ban multi folder with a 16" LW barrel A1 style.  In addition, you could add a .22 converison kit with it.  This way you can teach your daughter with the .22 until she is comfortable to shoot the .223.  I think the fixed stock post ban will be too much for a small child.  With the folder, you can at least adjust to her stature.

"big person's guns" are for big people. Handing over a high powered rifle to child who doesn't understand the consequences of its misuse is just plain irresponsible.

Sure letting her fire it once or twice for kicks is nice but let her grow up a little bit before she is shooting centerfire rifles on a regular basis.

AFARR,

I have a CAR15 set up for my 7yr old son.  You might have seen it/him in action at the last "pit session" over Memorial Day.  It's a 16"HBAR that I had Kurt'sKustom do a M4 job on.  The result is a barrel that is lighter than a M4 (smaller O.D. to begin with), and handles super nice.  I permanently pinned a telestock to the shortest position to finish it off.  Yea I know, there's debate on this, but trust me....you would have to destroy it to get it to move.   The result was a super-light carbine that is the proper length for his frame and he enjoys shooting it.  When he grows a bit, I'll buy another stock, move it down a pin, and do the same thing.  The shorter one will be saved for his younger brother.

A .22 short will kill just as dead as a .223.  The key here is maturity, not caliber.

sorry....had to rant!