[kengel]

Edit: Dammit...I noticed the "srock" typo in the title as I was clicking on "submit". It should, of course, say "stock"

I have my PTW assembled and ready to roll just in time to watch the outdoor season disappear. I guess that means I'm switching my focus to CQB.

The problem I'm trying to dance around is that even the Systema M90 cylinder is 10-20fps above our indoor field limit (400fps).

I'd like to create my own home frown M80 equivalent.

Anyone know if the spring inside the factory systema cylinders are swappable with standard systema (or any other) springs?
If so, has anyone got first hand experience doing this? Any detail would be appreciated (spring type, fps achieved, reliability, etc).

Thanks