
This January I purchased a JG AUG-A3, and have used it in several skirmishes since then. I have been pleased by its stock performance, and my only complaint would be the weight (and I sometimes find bb's inside the stock? I think this may happen when I am removing a mag...).
Now, I am looking to upgrade its internals.. I play in a fairly wide-open grassy/sandy/bushy area, and often find myself looking at people knowing I can't hit them at their range. While the gun does have some impressive range (relative to stock guns), I am looking to get some more out of it with internal upgrades.
I have never upgraded an airsoft gun before (my only previous gun is the Echo-1 E90, which I left stock). I have been doing my research as to upgrading a gun's accuracy, and it appears I have a few things to look at.. A tightbore barrel, a hop-up bucking, and a hop-up nub (?). I'm convinced these, when upgraded, will provide the biggest boost in accuracy...
What would you recommend I buy to overhaul my accuracy? For a tightbore, I would prefer a 6.03, so that the maintenance is a little less than that of a 6.01.
I have started leaning towards this Madbull 6.03 (the price appeals to me): http://www.airsoftgi.com/product_info.php?products_id=1231
What sort of hop-up upgrades should I look into?
If possible, I would like to keep it all under $100, as I'd like to have a little money reserved for an optic or low-mag. scope.
One final sidenote: I am planning on modifying one of my spare 9.6v minis to fit in the battery compartment of my A3. Are there any parts I should plan on upgrading due to greater stress on the internals(from the higher voltage/rof)?
Thanks all!

-Brazlo