There is a TON of good information in this thread and I wish I had something like this to read when I was doing my dedicated PRS build in 2015. Lot's of good points have been brought up, and if it's any consolation, this is what I have learned through my past few years of experience with gun building for this game:
Action - doesn't matter. Get something that a.) fit's your budget, b.) has an aftermarket and c.) gun smiths will work on. I started with (and still currently run) a Tikka T3 factory action, but a standard R700 or Savage also works well. If you're going aftermarket and want to keep the price down, have a look at Ultimatum (no import fee's and they offer a barreled action option), Defiance Tenacity (newly released at $885 US) or maybe try get on the ARC Nucleus order list (?). If you want to swing for the fences, as mentioned before, there are much better options available than Cadex (and customer service is meh), I am going Defiance on my next rifle, but Impact, Surgeon, Curtis, Tubeor, Kelby's, PGW, etc are all solid. DO NOT OVERTHINK YOUR ACTION CHOICE... rather overthink the:
Barrel - Much more important than the action, IMO. For the PRS game, Rugby Dave is right and weight is your friend. The average barrel used by top PRS competitors is a 26" M24/M40 contour barrel, threaded for a brake (5/8"-24 usually). I highly advise going heavy with the barrel, partially for the weight gains and partially for the heat dissipation gains. If you're going 6.5 stick with a 1:8" twist, but if you're going 6, the caliber can determine the twist (safe bet there is probably 1:7.5"). As for manufacturers, for sure check out Krieger, Bartlien, Benchmark, Hawk Hill, Proof Research (NO CARBON just their steel offerings) or Broughton, and I'm sure Gary will be able to bring them in for you. If you want to stick Canadian and have a relatively short lead time, maybe give the boys over at International Barrels in BC a shout and they will be able to help you out, usually for cheaper
Stock/Chassis - This one is also a never ending debate, but can be summarized really easily: BUY WHAT FITS YOU. There is no right answer. Don't know what fits you? Don't worry, none of us did when we started this game and most PRS/NRL competitors will tell you that they're probably on at least their second or third chassis/stock already. You're probably going to go through a couple of these, but a sneaky way to test a lot of really high end gear, without having to buy any of it is to volunteer as an RO for a match. Your profile says that you're in N.B, so there aren't that many national level matches around you, however, I am sure you could find your way to a club match! If you RO a stage, you get to watch and talk to pretty much every competitor that comes through, and more often than not, they will let you get behind their gun and try stuff out. That way, you get to watch what works and what doesn't (pay attention to how the stock/chassis works on terrain, barricades, odd angles, when the mag is compromised (tilting), etc.) and make a choice based on that.
Optics/Rings/Magazines/Bipods/Bags/you name it - will also be evolving as you go, and you will never stop collecting gear. Do not stress the little things, spend the money where it is needed (good optics and good rings (like more than $1000 on glass and $150 on rings)), and just go shoot. Look at the amount of guys out there (and in this thread) who will say "I don't actually shoot PRS, but..." or "I'm about to shoot my first match, this is what you should do...", don't worry about what those guys say, they still have the same amount of learning to do as you. Go to a match (or RO), talk to competitors and get your grubby little hands on as much as you can before you jump down a $2000+ hole!
It's up to you my friend, but have fun out there. Just my 0.61 cents,
- Kudu
Action - doesn't matter. Get something that a.) fit's your budget, b.) has an aftermarket and c.) gun smiths will work on. I started with (and still currently run) a Tikka T3 factory action, but a standard R700 or Savage also works well. If you're going aftermarket and want to keep the price down, have a look at Ultimatum (no import fee's and they offer a barreled action option), Defiance Tenacity (newly released at $885 US) or maybe try get on the ARC Nucleus order list (?). If you want to swing for the fences, as mentioned before, there are much better options available than Cadex (and customer service is meh), I am going Defiance on my next rifle, but Impact, Surgeon, Curtis, Tubeor, Kelby's, PGW, etc are all solid. DO NOT OVERTHINK YOUR ACTION CHOICE... rather overthink the:
Barrel - Much more important than the action, IMO. For the PRS game, Rugby Dave is right and weight is your friend. The average barrel used by top PRS competitors is a 26" M24/M40 contour barrel, threaded for a brake (5/8"-24 usually). I highly advise going heavy with the barrel, partially for the weight gains and partially for the heat dissipation gains. If you're going 6.5 stick with a 1:8" twist, but if you're going 6, the caliber can determine the twist (safe bet there is probably 1:7.5"). As for manufacturers, for sure check out Krieger, Bartlien, Benchmark, Hawk Hill, Proof Research (NO CARBON just their steel offerings) or Broughton, and I'm sure Gary will be able to bring them in for you. If you want to stick Canadian and have a relatively short lead time, maybe give the boys over at International Barrels in BC a shout and they will be able to help you out, usually for cheaper
Stock/Chassis - This one is also a never ending debate, but can be summarized really easily: BUY WHAT FITS YOU. There is no right answer. Don't know what fits you? Don't worry, none of us did when we started this game and most PRS/NRL competitors will tell you that they're probably on at least their second or third chassis/stock already. You're probably going to go through a couple of these, but a sneaky way to test a lot of really high end gear, without having to buy any of it is to volunteer as an RO for a match. Your profile says that you're in N.B, so there aren't that many national level matches around you, however, I am sure you could find your way to a club match! If you RO a stage, you get to watch and talk to pretty much every competitor that comes through, and more often than not, they will let you get behind their gun and try stuff out. That way, you get to watch what works and what doesn't (pay attention to how the stock/chassis works on terrain, barricades, odd angles, when the mag is compromised (tilting), etc.) and make a choice based on that.
Optics/Rings/Magazines/Bipods/Bags/you name it - will also be evolving as you go, and you will never stop collecting gear. Do not stress the little things, spend the money where it is needed (good optics and good rings (like more than $1000 on glass and $150 on rings)), and just go shoot. Look at the amount of guys out there (and in this thread) who will say "I don't actually shoot PRS, but..." or "I'm about to shoot my first match, this is what you should do...", don't worry about what those guys say, they still have the same amount of learning to do as you. Go to a match (or RO), talk to competitors and get your grubby little hands on as much as you can before you jump down a $2000+ hole!
It's up to you my friend, but have fun out there. Just my 0.61 cents,
- Kudu
). 
