I do all of my Highpower competition (.308Win for a match M1A) reloading on my 550. I really really love my Dillon FL Carbide sizing die. You still need lube, but it takes about 1/4 the effort to resize as it does with typical FL sizing dies (and you have a much lower chance of getting a case stuck in the die). It will turn out brass on the tight side (almost like a SB die).
Brass prep usually takes me a while. I tumble, then size. Then I wipe off all the lube (you could tumble again instead). I end up trimming every other reload. I like to cut my primer pockets the first time through to a uniform depth (or clean them after the 1st firing) to minimize the chance of slamfire in the M1A, and I also deburr the flash holes (again, first time through).
(I use a cordless drill to spin all my case prep cutters--Lee trimmer, deburrer, primer pocket uniformer, and primer pocket cleaner). Dillon makes a combination sizer/automatic trimmer, but it's spendy and it uses a special, non-carbide sizing die. And it's a little spendy.
Once the brass is prepped, I run in progressive mode to prime, charge and seat (no crimp).
The powder measure will certainly throw consistant enough for match accuracy at short range (300yds or less), but you need to understand it's shortcomings. I would definitely recommend that you polish the inside of the powder funnel (the thing that drops into the powder die). If you don't do this, you will probably find that extruded (stick) powders tend to hang-up or bridge in the funnel from time to time. Getting a smooth consistant stroke on the handle is key. If you bang the press or jar a case up against the bottom of one of the dies, the next charge is going to be pretty heavy. Sizing/seating effort is always going to be somewhat variable, and this will add inconsistancy, so I like to run the press with only one case on the shellplate at a time. I find that if I tap the side of the powdermeasure body before I drop the charge, I get more consistant results. I recommend that you weight and record the weights for 50 consecutive throws, and make a note when the stroke on the press is less than ideal--you'll quickly be able to anticipate out-of-whack powder drops. Mine started to get flakey when the measure was down to 1/4 full. Again, for 200 and 300yds, I was able to get slightly better than 1MoA loads (iron sights, match-grade rifle). +/- 0.3grs is not going to matter one bit. For 600yds, I weighed each individual charge--I am not even sure that it's necessary there for 1MoA accuracy, but it's the standard practice among highpower shooters, and I don't get a lot of opportunities to shoot the full distance--so I go with what works.
If I was working with Max or Near-Max loads, I would weigh each one.
I use short and long extruded powders exclusively because I want to minimize the amount of compensation that I have to use due to temp change.
I've never lost a point due to ammunition induced fliers, even when shooting IMR4064 straight from the powder measure. I got a Harrell powdermeasure for Christmas, but I still use my Dillon to size, prime, and seat.
If you're reloading for a polytech or norinco, definitely get some sort of case gage and use only milsurp brass. Measure a fired case and set your sizing die to bump the shoulder back by 0.002-0.003". The chicoms are notorious for being on the long side as far as headspace. If you set the shoulder back too far (0.005 or more), you'll see case head separations. If you follow the sizing die mfr instructions to set the die, you'll end up pushing the shoulder back by 0.008-0.010". Get a case gage.
Ty
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