Little bit concerned

[Triumph045]

All,

 

I'm fairly new to all this re-loading malarkey!!!

 

I want to work up a load for my Remmington 700 in .308 Win. I'm using 167gr Lapua OTM bullet (looks like a hpbt) fiocchi large rifle primers, Lapua brass, and Vhitavori N-150 powder.

 

In my Lee reloading manual (Modern reloading, second edition) it doesn't give me a Vhitavori N-150 option for a 167gr bullet, but it does say that a start load for 168 gr (jacketed bullet) is 38.6 grains of Vhitavori N-150, With a never exceed load of 44.5 grains. Now here's my problem, in my Speer reloading manual #14 it gives no options for a 167gr bullet, but it does say that a start load for a 168gr 30 match BTHP with Vhitavori N-150 is 43gr with a maximum charge of 47.0 (although the latter is a "C" compressed load (which I wouldn't go near anyway) my worry is that if I go with the Speer manual and ladder load to say 46.4g of Vhitavori N-150, I'm not maxing out according to Speer, but I'm well over the "never exceed" according to RIchard Lee.

 

Could someone please give me a steer as to where I'm going wrong?

 

Many thanks

 

Triumph045.

[baldie]

Use this one.

 

Its lapua's accuracy load, and it shoots in any .308 i've ever tried it in. It was so good in my AX, I did absolutely nothing with it.

 

44.8 grains [max load ] of vhit 150

 

Lapua brass

 

167 g scenar

 

I use BR2 primers.

 

OAL of 2.795"

 

Drop it by a grain, and play with the seating depth. Its the best .308 load i've ever used.

[JSC]

Well, in Quickload the 167gn Scenar and N-150, with a 26" barrel predicts:

 

Load A= Max pressure of 49115psi and MV of 2632fps using a charge of 44.5gn (106% filling)

Load B= Max pressure of 59135psi and MV of 2770fps using a charge of 47.0gn (112% filling)

 

So both are potentially compressed loads if you stick to the standard OAL of 2.8".

I'd not be too worried trying load A, but I'd definitely build up to load B.

I'd probably start at 44.0gn and go up in increments of 0.3gn to 47.6gn maybe and stop if I felt the bolt was becoming a bit sticky to lift.

 

However, it begs the question why you are using N-150 here, as it's a bulkier powder than some you could use for .308.

Are you trying to get to a particular velocity with this bullet or just looking for good accuracy at short range?

[Laurie]

As Baldie says, the Viht accuracy (also listed as maximum) load is a very good one. As usual for Viht it's a conservative loading, so definitely don't worry about pressures especially in a Remy 700 which if typical of the genre will turn out to be 'generously' throated.

 

http://www.vihtavuori.com/en/reloading-data/rifle-reloading/-308-winchester.html

 

I've just finished a series of small primer tests using this very combination, but in Palma brass, and the loading used throughout was the 167 Scenar with a rather heavier charge of 45.5gn N150, CCI-BR4 primer.

 

In the initial 'work-ups', 100 yard 5-round groups shot from a Stolle action FTR custom rifle off a bench were:

 

43.0gn ... 0.6" / 2,704 fps

 

44.0gn ... 0.4" / 2,737 fps

 

44.5gn ... 0.3" / 2,763 fps

 

45.0gn ... 0.6" / 2,786 fps

 

45.5gn ... 0.2" / 2,809 fps

 

46.0gn ... 0.7" / 2,828 fps (4 in quarter-inch + 1 lateral 'flier')

 

Palma brass / small primers usually produce slightly lower pressures and MVs for any combination, but the rifle has a 32-inch barrel, so you won't get those from your Remy if it a factory job.

 

There were no pressure issues at all even at 46gn with easy case primary extraction.

 

If you're intending any long-range shooting, find something other than the 167 Scenar, as well made bullet though it is, it is a low BC shorter-range number (ie 100-600 yards and starting to struggle against more efficient designs at the top end of that range).

 

JSC - I've used N150 myself in 308 often enough for shorter range matches even with 155gn bullets. Although MVs are down a bit on other suitable propellants (~2,900 fps for a 155 from a 30-inch barrel), I've found that precision is up with the very best combinations. One of my favourite combinations for club matches in an earlier FTR rifle was the Australian manufactured Dyer HBC 155gn that Bryan Fox used to sell for a very attractive £28 / 100 allied to N150 in Norma brass with F210Ms.

 

QuickLOAD massively overstimates the fill-ratio for this (and some other Viht powders) IME.

[JSC]

 

QuickLOAD massively overstimates the fill-ratio for this (and some other Viht powders) IME.

 

Agreed. And it exaggerates pressures, but better to err on the side of caution.

 

I didn't do much development with 167/168gn bullets, so I bow to Baldie's and your experience with these loads.

 

I did try a 168gn Hornady when I first got my 700 and from my notes it looks like I got 1/4MOA accuracy at 300yds using 39gn of N140, so that might also be worth trying maybe?

[Triumph045]

Thanks everyone, really appreciate all the advice. I'll let you know how I get on.

 

Regards

 

Triumph045.