Cheers for all the help and advice guys, sorry muir but I'm with RPA 6mm br on that one, if that was the case we all might aswell just throw are coal gauges away and just load what it says on the box, after all who want to spend ££££'s on a custom made rifle and then just run factory ammo through it
Well, that actually IS the point about the 6.5mm Creedmoor - those who wish to buy a custom rifle and get good results from factory ammo will do so. In the USA, the factory ammunition is affordable and many users stick to it. Hornady, Ruger, Savage and Dave Kiff of Pacific Tool & Gage came up with a standard chamber reamer spec that is optimised for the 140gn Hornady AMAX at exactly 2.800" COAL as the original raison d'etre for the cartridge was the 'match' division of American Hi-Power 'XTC' competition, a three-position quasi-service rifle discipline involving rapid fire and in-stage magazine changes and where the ammo has to fit and feed ultra reliably from standard 'big AR' and short action bolt-rifle detachable magazines.
That's not to say that you cannot or should not fine-tune handloads, but it gives people a good starting point. Most US handloaders of the cartridge also use H4350 even those who've tried alternatives. With the powder being expensive here, and often difficult to get hold of, it makes sense to find an equally good alternative that has a more secure supply chain. I believe that Reload Swiss RS62 may become the European alternative to H4350 for this cartridge, but we'll have to see.
So far as COALs go, I found that a rifle chambered with the standard chamber that almost everybody uses, PT&G print number (10618) provides 15 thou' jump for the 140 AMAX at exactly 2.800 COAL and the 120 at 2.720 as per the factory specs. Dave Wylde at Valkyries uses this reamer as does every other UK rifle builder that I've spoken to. And yes ... subject to individual smiths running the chamber reamer into the blank a thou' or two different amounts every custom rifle chambered with this standard reamer will have the same freebore plus or minus 0.002" or thereabouts.
Hornady presumably hopes that even those users who handload will buy its AMAX bullets as a proven reduced work option. Other makes / models of bullets may obviously produce different COALs. In a custom rifle chambered with the industry standard PT&G reamer, I got the following COALs at 15 thou' 'out', but people should
always check their own chambers:
123gn Scenar .................... 2.743"
139gn Scenar .................... 2.759"
140gn Berger LR BT ............. 2.800"
142gn Sierra MK ................. 2.800"
140gn Nosler CC Match ........ 2.748"
and some 15 thou' 'in the lands' for VLD forms:
136gn Scenar .................... 2.727"
130gn Berger VLD ............... 2.861"
140gn Berger VLD ............... 2.865"
I'm a little amused too at a forum member with 6BR in his or her forum name implying that off the shelf loads are sub-optimal. 300 metre ISSF 3-position competition isn't very popular in the UK, but it is the biggest centrefire rifle discipline by far in most European countries and attracts serious media and online interest, big prizes and corporate sponsorship that we just don't see here. What do the top competitors use? Factory Norma or more often Lapua 6mm BR Norma fodder. As is the intention with the Creedmoor, custom rifles are built around the ammo spec. Nothing exactly new here - the .22 Long Rifle rimfire competitors have done so for generations.