How to measure length of pull for youth gun?

[nutterbug]

Bought a H and R 223 for my son, he's 6. It's still hard for him to get it fitted right? How can I measure his length of pull, I'm gonna cut the stock off? It's an old best up gun, but still shoots good?

[Outback77]

If you do it right, you can cut off 1 inch sections and add them back as he grows. There are videos on line.