FWIW, I've always reckoned the standard 6.5X55mm underrated as a good all-round target cartridge, especially for the clubman looking for good performance allied to reasonable barrel life. It has excellent brass available and despite the nominally slightly larger case-head diameter than the ubiquitous 0.473" Mauser / '06 / 308, is usually a straight rebarreling job.
In Europe, including here in the UK, M1895 Swedish Mausers are usually the rifle to beat in Historic Arms comps when we talk about the cartridge in its original low pressure form. As well as often amazing precision for elderly rifles, its mild recoil makes it very easy to shoot compared to say the '03 Springfield.
We also see a lot of really good results from heavy-barrel Tikka T3 Varminter and similar factory rifles in our 'Factory Sporter' class in 600 and 1,000yd bench rest. They've pretty well taken over the top slots from equivalent .308 Win H-Bar Remington 700s and more surprisingly from the Savage 12 F-Class in 6.5-284. (The demise of the Savage is probably due to commercial + ITAR issues. Some years back we could buy this rifle at a really attractive price - not anymore as it now costs us little short of what many custom rifle builders charge. With the early wave of Savages having shot their 6.5-284 barrels out, we simply cannot get factory replacements at any price and a match barrel substitution takes the rifle out of 'Factory' status.)
I bought just one of these 6.5-284 Savage F-Class models new at a bargain price in 2008, but it was a disappointment. Not so bad that it could be returned as unsatisfactory, but it just never produced the quarter-MOA groups that the best of the breed saw - double that was good, three time it the norm. It never produced full 6.5-284 MVs either, loads that gave a 140 ~2,950 fps + in a friend's FS-Class winning Savage barely made 2,800 fps in mine. Giving it lots of patience, different loads and running-in made no improvement at all.
I eventually came to the conclusion that it was just a relatively poor barrel, so had a 30-inch True-Flite 6.5 Heavy Palma put on chambered for 6.5X55mm, no Dave Kiff special here either, just a standard PT&G CIP/Saami spec job. With the rifle otherwise as it came out of the box, this transformed it - not into a 0.1-MOA BR rifle, but into one that would regularly produce quarter-MOA with 139/140s at over 2,800 fps and with barely double-figure ES values. In testing, I got the 139gn Lapua Scenar up to almost 3,000 fps (2,999 fps 5-shot average) with Viht N160 with only slight high-pressure signs - but this was silly and pushing the cartridge much too far. In fairly limited testing, I got my best groups with the Viht N165 I had left over from the rifle's 6.5-284 incarnation - the most widely used powder for that cartridge in Europe. A tentative match load of the 140gn Berger BTLR and N165 gave something in the 2,825-2,850 bracket, quarter-inch groups and shot very well at mid ranges in one or two F-Class matches.
At this point, other Savage / UK related matters got in the way. My 308 F/TR build was to be based on the supply of a bunch of 'tricked-up' Savage 12 actions allegedly en route to to my gunsmith. Getting on for three years later, they're still stuck in the USA somewhere waiting on an export permit. Unaltered Savage PTA actions had been a great buy here at the time I bought my rifle - as in the US - but not any longer, doubling in price ...... now you can't get them at all. So, the 12 F-Class was cannibalised - the action and scope rail are part of my current F/TR rifle and doing very well indeed, the barrel will be reused at some time in the future, the stock was sold.
Out of interest, I tried a couple of 6.5X55mm factory rounds in the rebarrelled F-Class. Lapua 139gn Match is loaded to 6.5mm SKAN CIP levels, which should be warmer than US SAAMI and gave 2,596 fps against a claimed 800M/S or 2,625, 4 groups averaged 0.59-inch at 100yd, ES was 35 fps and SD 13.5 fps. Hornady 140gn 6.5X55mm PSP hunting ammo produced an average 1.1-inches from four groups, 2,487 fps average MV 126 fps ES and 38.4 fps SD - kind of mild!!
Whe I rebarrelled, I did look at the AI version, but the unavailability of dies put me off, plus the extra cost of getting a reamer. There is a view that an 'improved' 6.5X55mm may be the ultimate practical 6.5 match cartridge as the 284 version has a larger capacity case than needed or is desirable. I'd like to test this out, but there is a great deal going for the standard version of the cartridge for users who don't aspire to getting the last 100 fps for 1K shooting and want a good straightforward proposition. And yes, you do have to trim the cases rather often - my least favourite handloading chore.
