I did say before that I’d pass a little more load data on. Late last year after a new barrel went on, I decided to give Viht N150 a try. I’d avoided the powder previously after hearing from Jerry Tierney over in California that he’d had some worrying pressure spikes with it,
Sorting a Savage Part 2 THE CONCLUSION By Laurie Holland
tout this as a 1000 yard load but it shows a great deal of promise for the shorter-range club shooter, has no recoil to speak of and will probably give 4,000-5,000 rounds barrel accuracy life. The 80.5gn Berger BT at 2800-2900 fps is gaining a good reputation too and I’ll try this bullet later on in the year in my F/TR rifle as well as another Savage .223 we’re working on – a rebarrelled ‘sporter’ designated as ‘an affordable clubman’s F/TR rifle’.
Figure 3: With the tension at just under 15 in/lb, a return to the 90gn VLD / Re15 ammunition combination appeared to have got the rifle shooting well again
Figure 4: Graphed
getting a huge rise in MV and pressure signs from a 0.2gn charge weight increase. I’ve always liked this powder with heavy bullets in the cartridge and decided to give it a try, albeit acting very warily.
Five batches in well-used Lapua match brass, CCI-450 SR Magnum primer and charges of N150 rising from 23.6 to 24.0gn in 0.1gn steps (weighed on Acculab high-quality electronic scales to accurately allow such small differentiations) produced 0.2 to 0.7” groups, only one exceeding the half-inch. The top load produced a modest MV of 2,641 fps with a small ES of 9 fps, so there is scope for working it up a bit higher. Before shooters scoff at such ‘low performance’, run the 90gn Berger BTLR’s external ballistics on a decent G7 based program. The 800 yard wind-drift for a 2,640 fps load is 6.7-MOA in the classic 10 mph 90-degree crosswind which is better than that of the NRA’s RWS .308W / 155gn SMK ammunition, assuming that the latter produces a full 3,000 fps MV from a ‘tight-bore’ 30 inch barrel.
Retained velocities and wind-drift values for this load fall between those of the ‘old’ and ‘new’ 155gn Sierra ‘Palma’ MKs at a full 3,000 fps MV in fact. I wouldn’t
19
elevations of the 20 shots in the 600yd Diggle F Class competition corrected to a common elevation setting on the riflescope. Despite the use of the Re15 load, the problem has not been solved! 0 = perfect elevation with a strike on the V-Bull centreline; low shots have minus values; high shots have plus values. Shots 13- 19 suggest a solution may be close
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