Pete, I would argue that configuration does not matter; however capacity MAY - and THAT may vary with regard to bullet weight, burning rate and bulk:density; it could get complicated! ;)

With regard to tuning, in the last couple of seasons, subsequent to seemingly MINOR changes, I have observed some startling IMPROVEMENTS in the grouping of particular barrels - so startling, that had I not been a participant, I'd likely dismiss even the notion that the adjustments might "take"!

Most notably, was the tune of a HBR rig, owned and piloted by Dale Fritts at one of last summers BOONE VALLEY IKes Score Events : during the warm-up match, both the sighter and record bulls on Dale's target looked like the makings of a LONG and dissapointing day - though he was able to keep all of the shots on the ten ring, THAT was due to happenstance! He was shooting PATTERNS - probably about 0.40" grouping.

I was shooting on the bench to Dale's right - my sighter consisted of a "middle teen" five-shot group, followed by 9 out of ten Xes on the 'record' bulls (I do THAT on the warm up - it provides a better perspective of TRUE ZERO, as opposed to sighter bull ZERO) - obviously, conditions were much more favorable than Dale's target made them appear! Being familliar with both the reamer and bullets Dale was using, I questioned him regarding the "load": "how  much JAM; powder charge weight, etc. His responses indicated that he was "in the ball park" - that is, his target should have looked a LOT better (Dale is a very good competitor - but he was new to HBR) - the only thing left to do was suggest a TIGHTER neck-size bushing . . being an attentive student, Dale DID have the .324" diameter bushing that I had recommended he purchase and keep in the tackle box! ;)

I suggested the he load a few using the smaller bushing (he had been using the more conventional .327' variety) and, during the first record match, shoot a couple of groups on the sighter - maybe things would get better . . or worse . . . Dale determined to simply skip part of the lesson and loaded ALL of his cases using the .324" bushing . . and he proceeded to kick our posteriors until it HURT! ;) For his particular barrel, the difference went from being fortunate to scratch out a ten, to having to be an IDIOT in order to miss the X-dot - the rig became "automatic".

So, the lesson here is to never give up . . and, in my opinion, make a BIG change  - B4 making tweaks, which may or may not provide a readily observable change in performance, CRANK the wheel and see what happens . . .

By the way, I still haven't collected my due! ;) After changing the bushing, Dale went on to shoot a winning 499-something HBR agg, which he then combined with with a 499 VfS, which added up to claiming the IBS Two Gun (score) Record - a nifty 998-44X! Once Dale has a tuned rifle, we're in DEEP Dooo!

But, if I'd just kep me mouth shut, I guarantee, someone else would have won the HBR leg, and Dale would not have establisheda new record THAT weekend - he'd have been depressed . . . I still have a difficult time believing that the neck bushing made such a dramaticlly positive change in the tune! Oh, then, yours truly proceeded to shoot his wel tuned .30x47 like . . well, like an IDIOT! Meanwhile, Dale took his now SHOOTIN' rig and demonstrated his superior shooting and decision making abilities! ;)

At a BR tournament, the winner ALWAYS has one of the best tuned rifles AND a fully functional computer working together!

Keep 'em ON the X! R.G.