Great to see you giving the reloading scene a chance! Makes me wonder if your 6.5x47 was a casualty of timing...
I learned a lot of stuff searching for that "perfect" load for my JP (which isn't going to be exactly applicable since NO two rifles are the same and because it was a heavy/long barreled set up) but there are some generalities that I'm sure will hold true.
-DONT spend a lot of time (or money) on brass for a gas gun. Coming from a way bolt gun heavy background, this was my natural tendency when looking for better accuracy. Time and again I'd spend hours and hours sorting/prepping/annealing ect... then come back from a range trip with my ammo box of 50 perfect brass less the 8 that managed to disappear, the 5 that got ruined, the 3 someone stepped on, and all 34 dinged, scratched dented. Bottom line is you need to find as good of brass as you can afford to think of as DISPOSABLE, not an investment. As cool as it is having a precision rifle that fires as fast as you can aim, your gun WILL throw your brass across the room, into the mud, and under every rock. Every time. And beat it up. I had a serious mental hurdle with this issue. I found in the end that my gun liked lake city once fired brass just as much as the expensive much fussed over lapua/win/federal/ect... I spent a bit more time sorting/and swaging but ZERO time in detailed prep, and saved (a bunch) of money, time, and heartache when they didn't all come home.
-Unless you *have* to use an extruded powder due to lack of availability (I know what this component market is like) I think you'd be better off to use a spherical powder. There is definitely some great accuracy to be had building loads with 8208xbr, varget, mine loved 4895, and the others recommended above... but I personally would only look there if I couldn't find any CFE223, BL-C(2), TAC, A2520, H335, PowerPro2000MR, or WIN748. If done correctly (this is a large "if") ball powders will be just as accurate as extruded, and save you many hours at the loading bench.
This debate has deep, deep roots, and many people feel strongly one way or the other about this topic... my $.02 goes like this: My bolt gun will shoot 0.2-0.3 MOA at my home range (100, 200 and 300 yds only unfortunately) all day long. That requires 45g of varget, federal 210m primer, a 168g Nosler Custom Competition and Lapua fully prepped brass. Weighing each charge and spending that much time in prep is worth it for me personally for that level of precision, at the VOLUME that I shoot my bolt gun. My brass stays pristine, and I feel like I've shot a TON if I go through a box of 50.
When I was shooting my gas gun a lot, 3/4 moa was all I was capable of as a shooter with that platform. Gas guns are MUCH harder to shoot well. My gun would approach 1/2 moa performance, but I couldn't (consistently). Come to find out 3/4 to 1 moa was all (usually more than) I needed to have all the fun I could afford smacking steel, popping various containers of water, or reducing the local predator/pest population. The smallest units I would load would be multiples of 100, not 20 or 50 at a sitting like I had always done before. Bottom line for me comes down to volume. The end result is well within acceptable limits, and its WAY faster. Semi auto's are at their best in a target rich environment, and that boils down to higher volume shooting.
So, empirically the pros and cons are like this: Ball powder will throw charges volumetrically at or above the level of precision you can weigh extruded powder if you have good equipment. This nets you easily 3 to 4 times the production using a single stage press and larger batches, and if you end up with a Dillon or other progressive set up you will gain exponentially increased levels of production.
The down side is that ball powder can be more finicky to work with, pressure curves can get spikey, and it WILL be more temperature sensitive. I also found that primer compatibility tests were useful to get my velocity extreme spread down, where extruded powders usually work acceptably well w/anything. This wasn't a big deal for me... I didn't mind fussing around a bit more in the development stage, and knocking your load down a half grain in the summer was a VERY small price to pay for having copious amounts of ammo quickly, with little effort.
I started with a single stage rock chucker and RCBS 1500 scale, and was able to keep up production-wise if I threw charges of ball powder and loaded in batches of 100 or more. Then I got the RCBS Chargemaster auto dispenser for my scale, and a Redding T7 turret press... couldn't find CFE223 (AWESOME powder btw) or BL-C(2) anywhere, and found out my gun absolutely LOVED IMR4895. Having all my dies set up and interchangeable would let me auto dispense, seat, check and crimp each round at about the same speed I could before with my Harrell powder meter and single stage press. Several pounds of TAC became available during the ammo shortage, and I found my gun loved it as well.
-Projectiles have more to do with your intended use and barrel preference than anything. For hog hunting I think I'd go with a 150 ballistic tip, or a 150 SST/GMX, a Barnes ttsx, or any of the bonded bullets. Definitely something tough, and preferably the same weight as your target load so as to have a similar trajectory for field expedient bullet drop estimations. My barrel preferred seating depths on the short side, which worked well when I had to crimp to avoid bullet set back. That brings me to-
-Neck tension is a big deal for semi-auto's, because it (and/or crimping) is the only thing holding your bullet in place while the bolt carrier group is kicking its ass from mag into the chamber. Crimping works well, but necessitates trimming every case every time, which is a huge pain in the ass. I recommend getting a good quality name brand full length resize die (I think the small base dies are overkill) and polishing the expander ball down until you get at least .002" of neck tension, and as much as .0035". The name of the game is making sure that the bullet stays put while its getting violently slammed into battery. Any more neck tension than right around three thousandths is wasted. That is what I've found to be the elasticity limit of brass... as in the bullet is just "resizing" the neck if you try to make it any smaller. If you are getting unexplained fliers in an otherwise good load try single feeding a group by hand into the chamber and closing the bolt on top to avoid disrupting the bullet seating depth as a test to eliminate bullet setback.
That's about all the stuff off the top of my head, but if there is ever anything to do w/reloading you want to chat about please feel free to hit me up, its been my main hobby for about 15 years and I pretty much always enjoy "bench racing" with fellow enthusiasts! =)
When I really sank my teeth into the gas gun handloading challenge one of the books that I read on the topic that helped me the most was
Handloading for Competition by Glen Zediker. If you are a bookie type or like to read I recommend that one for the tons of great info (his writing style takes some getting use to though... he is apparently very southern, and likes to use various figures of speech and made up words).
Zediker Publishing Yukon
