here's a PM I got from someone who just posted a review on Arnies:
"Funny question to ask, The M14 SOCOM takes large type batteries as well as the mini types so a large 9.6v will fit. I use the 9.6v Killer by Giga Tec which is one cell smaller than the Sanyo Eagle Force, It will rattle a little so I used some packing foam to keep it from bouncing around inside."
http://img133.imageshack.us/img133/9...1mediumlh8.jpg
Full review:
http://www.arniesairsoft.co.uk/forum...6&hl=M14+Socom