6br loads

I currently shoot a Blaser LRS2 in 6BR with 8 twist barrel. It shoots the Lapua 77FBHP great with Lapua brass, Fed 205M a stout load of N135 with the bullets jammed about 10 thou. I am just able to reach the lands with the 77's; they're in the neck about 3-4mm. However, I would like to try some of the shorter varmint bullets for absolute humane kills. Informal ballistic testing on water bottles/fruit/veg shows that the 77FBHP can produce pencil holes compared to total destruction with V-Max/Blitz King etc. So, I have some Sierra 55 Blitz King's to try. Can you suggest an OAL given that the 55's cannot reach the lands. I tried with the Stoney point gauge but the bullet was barely touching the case neck! Also, can you suggest a starting load for the 55's? I have looked on 6mmBR.com but most suggested loads are for the obscure American powders. I have N133, N135, N530, N140, Re 15 and a bit of Varget at my disposal. My last question is, given that N135 is such a great powder for the 6BR and N530 is, according to Vihtavuori of a similar burn rate (and high enegy), why is there is virtually no mention of this powder on 6mmBR.com and not one suggeted load for N530 and the 6BR in the Vihtavuori load manual? Given it's burn rate and high density one would think that N530 should be a great powder for 6BR and the 55-70 grain bullets.

Dear Steve,
It's very difficult to comment on your loads / results and answer your questions that have arrived via Blaze Publishing and Vince Bottomley as I haven't used directly comparable loads / components, the nearest to the 87gn V-Max being for the 90gn Lapua Scenar where I don't find much correlation with your loads / findings.
I started doing a series of varmint bullet loads some time back in 6BR but have only done the 55s to date, as other things (like .308W and the GBFCA League F/TR) have got in the way. I will resume this programme at some point and work up to the 85s and 87s, but that will be a while off yet.

On MVs, I'd recommend cross-checking your readings against somebody else's kit as they seem very high. A mere 3% error can add / subtract 100 fps near enough, and this may be the issue here.
So far as whether these MV /MEs are feasible - just maybe, but unlikely in a 24" barrel rifle with a fair bit of wear. A reasonable, but not infallible, rule is that if you can get x,000 ft/lbs ME from a cartridge with one particular load in a rifle without exceeding safe pressures, you'll get it again or something close with a different bullet weight in the same rifle.

Optimum 6BR loads with 105s on the 6mmBR.com website and achieved by people I know are around the 2,900 fps mark from 28" barrel target rifles. This equates to 1,961 fps. Remember, a lot of the data from sources like this are worked up by people with custom action rifles like the BAT and factory actions with larger looser firing pins get primer cratering / piercing at lower MVs with the small size primer. I used to run at nearly 2,900 with 105gn Lapua Silver Scenars, but got too many pierced primers, so now run at below 2,800 with 'naked' 105 Berger VLDs in my Remy 700 28" barrel rifle - 1,795 ft/lbs which I think is a reasonable ME figure for the cartridge. On that basis, 3,045-3,050 fps are 'realistic' MVs for 87s.

Without being 'funny' about it, with the number of things you obviously want to try or consider, you really need the QuickLOAD internal ballistics program. This is available from J.M.S. Contracts for £115 and lets you model potential loads with virtually any powder and bullet you can think of. That's the only way you'll be able to see if say N530 is likely to work out in practice and what would be a sensible charge level. J.M.S. phone number is 01444 400126

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