ruger marK III problems help

[cdpII]

Hi i just bought a ruger mk III target model and shot about 200rds out of it when i got home i started to clean it. I removed the mainspring housing and then tried to pull the slide back just as the book showed but the slide only came back about an inch, so i reinstalled the mainspring and tried again but the mainspring is now jammed also it only moves out about a half inch. does anyone know what is wrong/ how to fix it?

 

[Bullseye57]

This looks like a double post - moderator please remove this post there's another one created three minutes earlier.

R,
Bullseye