John,
Great article. I only own a Cooper 57M Custom Classic in 22LR and if it's any indicator of other Cooper's, then they're all keeprs; in both accuracy and build.
Just the other day, on a different forum, a gent asked about this wonderful caliber. I gave a pro/con list. This is it.
I own two 6.5x47's.
Pro
1. small primer pocket allows more brass around the primer and thus allows more pressure which means more velocity.
2. Case is short enough to fit short action.
3. Case is short enough to never worry about bullet intrusion into powder space.
4. Good shoulder and body angle to greatly or totally reduce neck growth thus reducing or eliminating the necessity to trim necks. I finally trimmed a few necks after about 10 firings.
5. 6.5mm with numerous hunting and target grade bullets
6. 6.5mm with numerous bullets with high BC's.
7. Lapua brass
8. .308 case head so many many reloading items available for .308 case head dimensions.
9. .308 case head so many many short actions with .308" diameter bolt faces; great for custom builds.
10. Smallish case capacity means it's not a powder hog.
11. Many after market items available for .308 case. Example; Accuracy International mags in both 5 and 10 rd configurations.
12. Numerous bottom metals built around the AI mag.
13. Mild recoil, even with heavy for caliber bullets.
14. Mild recoil means you can sometimes see hit/misses if far enough out from muzzle.
15. Numerous proven bullets that greatly succeed in both the hunting and target arenas.
Cons
1. Smallish case capacity means it won't stand shoulder to shoulder with the big cases but IMHO will do so with the 6.5CM and 260 Rem. My 24.5" Pierce/Broughton can push 140's up over 2900 fps with ease.
2. Some say the small primer will not fully ignite the powder is super cold temps; say 0 deg and below. I've only tested mine to about 10 deg with zero ill effects.
3. It's not a 30+ cal.
4. Some actions need the firing pin hole bushed otherwise primer cratering extrusion can be excessive. My Surgeon action is nearly so. My Pierce action does not suffer that problem.
5. Expensive brass
6. Only source of brass is Lapua which can mean occasional shortages.
7. Occasional shortages of popular bullets such as the 140 Berger VLD.
I hope I've given a fair representation.
Another thing John. If you'r only getting 2700+ fps with 140 Bergers, you're either using the wrong powder or just not letting it breath. As you said, it's a round that can handle high pressures. With my 26" Broughton, I was getting 2950 fps with Rel 17 and 1/2 MOA 5-shot groups with the 140 VLD. Not as much with bullets that have more bearing surface like the 140 Accubond and Partition but still in the high 2800's. These two bullets, having more bearing surface, present pressure signs earlier than the VLD with it's shorter bearing surface.
All in all, I love the -47 and expect to have it in my arsenal until the end of my life.
Thanks,
Alan