One solution I'm thinking might work is a correctly sized recoil spring plug with an end hole, like on a 1911.
A modified version of one of these:
http://shopwilsoncombat.com/Replacement-Plug-Full-Length-Guide-Rod/productinfo/25P/
Does anyone know where I can find a non capture guide rod for a Sig P320 Compact? I see GGI make a fat rod for the full size version, but have drawn a blank trying to find anything for the midsize Compact.
Thanks.