hopdoc,

I agree with 400

And everything I have seen where people rechamber DR's do so to increase value. To be honest with all the stuffing around and time and effort in trying to find or make a "cheap" DR you might as well just buy one and get on with having fun.
I think in the end you don't end up saving anything and often end up having trouble selling it afterwards anyway.

Just my HO.

500 Nitro