The pursuit of the best performance is indeed not inexpensive.I know that virtually any shooting discipline is not an inexpensive hobby. But how do those of you with a modest income deal with all of the above? Or should I switch to bird watching where all I absolutely have to have is some fairly decent binoculars?
Finding the best performing ammo is never about finding the "brand" of ammo a rifle allegedly "likes". The major match ammo makers all make batches of ammo that will perform well in a given rifle. These batches are called "lots" and every variety of match ammo -- eg. for Lapua, from most expensive to least, X-Act, Midas +, and Center X, and for Eley, the most expensive is Tenex, followed by Match and Team -- is produced in these batches or lots.
Performance isn't based on the price of the ammo. Some less expensive lots shoot better in a given rifle than more expensive one.
Perhaps the most effective way to find the best performing lots of ammo available is to send your rifle (or go with it) to an ammo testing facility such as Lapua's in Ohio or in Arizona. There's a wait to get an appointment, but they will be able to test a number of lots of ammo in an attempt to find one that performs well. There's the caveat that this doesn't guarantee you that you'll be able to get a lot that performs exceptionally because they can test only what they have available.