Pet load

[johnd]

Anyone got a long range load for 185 jug's using vit 540 out of a 32", 1-12 barrel thank you.

[Laurie]

Not N540, but N150 and N550. 540 may be a little fast burning to get the best out of this bullet. I'd very good results with 46.3gn N550 in Lapua standard brass and with the F210M primer. That was in quite a long-throated chamber with the 185 BTLR nearly optimally seated. Start ~43gn and work up. 46.3gn gave around 2,800 fps from a 30-inch Broughton.

 

Many people shooting this bullet in F/TR switched away from N500 series powders a season or two back. You do hammer the barrel throat with maximum loads, for what is maybe 50 extra fps at the end of the day. It's quite easy to lose accuracy in 1,500-2,000 rounds with such a diet.

 

N150 loads seem to vary a lot between barrels and throats, weights that work well in some barrels give serious over-pressures in others even when chambered with the same reamer. I'm beginning to wonder too if Viht has lost some of its legendary lot to lot consistency, as Eurenco has allegedly been switching production of some grades between different plants that it owns.

[johnd]

Hi Laurie, thank you for you're post I've had good results running Lapua 155 and vit 540 I was thinking it might work with the 185 jugs as well, as you say I may be better off with vit150 or maybe varget for both?.

[Laurie]

If you want to use a Viht N500 series powder with 155s, N540 is absolutetly the one to choose. Try it with 185s, but it's just a bit on the fast burning side. Mosxt Americans use Varget with this bullet and it'll likely give you good results. I'd use N150 myself in preference, cheaper for a start especially if you buy one of the big bottles (3kg, 3.5kg?).

 

I've also used N150 for years with 155s in 308 and often got my best groups with this powder for the bullet weight. Velocity is a bit down on N140 / and even more so N540 at around 2,850 to just over 2,900 for a 30-inch barrel, so it's not a great choice for 1,000 yard comp loads. It makes an excellent 300-600 yard combination and should be kinder to the barrel than many.

[johnd]

My main reason for using vit 540 is because I always shoot silver scenars and need a bit more speed to keep up with them , 3050 is easily achieved using 155s from a 32" barrel with no pressure signs.I will work up load using N150 as most of our comps are held over 3,5 and 600 yards. If you have a moment Laurie I'd love to hear you're views on gain twist barrels, example 12 1/4 to 12 for 185 jugs in 308 cal, thank you.