1) Good deal. In that case, I would most CERTAINLY plan to run 80's from magazine. They can be pushed at the same speed as a 75 or 77 "magazine" AR-15 load (or faster), simply because you have the room in the mag to load them at 2.45"+ and still repeat.
2) Stick with the Lake City; it's good for 1/4 Minute, even in an AR, and can 20X clean every Highpower target made. In a normal .223 chamber of 0.253"-0.255", it has ample neck clearance for consistent velocities, which of course you will need.
The Lapua, honestly, is very nice brass, but unless you have a 0.254" neck or better, in our sport, I think it can cause pressure and elevation issues unless turned. It ends up at a loaded round diameter of 0.2495"-0.250". For XC, with possibly 100 rounds fired between cleaning, I just think more clearance is more better.
Shoot the LC as-is, anneal at 3, and toss it at 5...you got your money out of it.
3) Good. I'm not saying VLDs aren't worth the trouble, but I AM saying that unless you are an extremely accomplished shooter in XC, your time spent dicking with the VLD would have been better spent at the dryfire range.
I dearly love the 80 SMK and the 82 Berger. That being said, some more work of mine this year with just the 77 SMK has yielded some pretty impressive performance in terms of sheer accuracy, even jumping nearly 1/4".
4) You have illustrated to me that--forgive the term--you are asking for a somewhat run-of-the-mill chambering (you're not looking for some extremely long 90-only chamber that will restrict barrel life to 1,000 rounds).
As the Wylde (freebore of 0.062") is intended to put the 80 SMK at the lands at ~2.475" COAL, and usually shoots best somewhere between 0.025" and 0.040" jump, that would give you a theoretical throat life of 50-65 thousandths with a Wylde....maybe 3,000-3,500 rounds before it would need to be set back to keep them in the magazine. That's assuming you stick to the 0.100" erosion = dead principal.
With the Wylde:
If you choose a premium cut blank, don't hit the powder can too hard, and pay attention to concetricity, your barrel's surface would probably outlive it's throat, in regards to the magazine length. SO maybe the Wylde is actually a little longer than you want. Now, if you went with a Wilson or similar buttoned blank, maybe it dies at about the right time (2,500-3,000 rounds)...but that's kinder false economy to me.
Shorter: to pick up some barrel life and keep 80's in the mag, I think you might want something a touch shorter than a Wylde.
Best thing would just be to call up JGS or Manson and see what prints they have that would put the 80 SMK at lands somewhere between 2.450-2.460". In terms of length ONLY, that would be about a "NATO", as they are I think about 0.055" freebore.
Trouble with the NATO reamers is the freebore diameter (YUGE at +0.002" over bullet). Don't allow that to be run into your barrel unless you like the hotdog + hallway effect.
Were it ME doing what you are, I would want:
-0.253" Neck,
-0.050" Freebore length,
-1.25-degree leade,
-0.2240" Freebore diameter.
If you want a little more life, but a touch longer throat, make that a 1.5-degree leade rather than 1.25.
-Nate
