308 Win w/ N150

[Longone1]

Is anyone shooting 308 Winchester w/ 175 Sierra or similar and N150? I have a 30" Lilja 3 groove and would be interested to hear from anyone that has had + or - comments about this combination. Hoping to make it work for 1000 yes.

Longone

 

[Minesweeper3433]

My favorite recipe so far is N150 and 175 VLD's from berger. Works great but I get best accuracy right at max pressure so I'd rather not share charges.

 

[Longone1]

I appreciate that. Is N150 temp. sensitive?

Longone

 

[Laurie]

N150 works very well with 155 to 200gn bullets in 308. It's down on MVs with 155s compared to say H4895 or VarGet, but usually gives very good accuracy and barrel life. It's very well suited to 175/185s, but the 175gn SMK is not a great choice for 1,000 yards - you'll struggle to get enough velocity with this relatively low BC bullet to be competitive at this distance. The 175gn Berger LRBT is a better choice and also has a short bearing surface so can be driven faster than the SMK within acceptable pressures.

However, unless your rifle is very short throated, the 185gn Berger LRBT 'Juggernaut' is by far the best choice in this bullet weight category. It can be a very effective combination with N150 turning out 2,800 fps or more in a suitably chambered 30-32 inch barrel.

No, the powder isn't particularly temperature affected although it may not be as good as the Hodgdon Extreme powder grades in this respect. we don't worry about it all in the UK, but then again we don't get really hot here. However, Bob Pitcairn the Canadian top national and international sling shooter uses N150 in .223 Rem long-range loads with 90gn VLDs and one of the reason he likes it it is its lack of temperature issues. And, .223/90 is a combination that really can suffer from heat induced over-pressure, believe me! Viht N550, the same powder but infused with a percentage weight of nitroglycerin, gives very much higher MVs - but it IS relatively temperature sensitive, so be sure it's the single base N100 series version you're dealing with.

 

[Dgd6mm]

Jim, Laurie gave you some verygood info. It helped me also.

 

[Longone1]

I just got my box of Juggernauts and plan on giving N150 a try. Not a lot of starting data out there. I also picked up a copy of the Berger manual and of course they don't list 150 with that bullet.

Longone

 

[Laurie]

I used to run it at 45.1gn in Lapua brass in a minimum SAAMI chamber throated to suit the longer 155s seated pretty far out and the 185gn Berger LR BT a tad deep. I have seen people over here run at 46gn plus with this bullet in Lapua cases.

A great deal depends on brass and your freebore though. My 45gn equates to ~46gn in Winchester cases, and freebore can affect the usable and safe maximum by two or more grains.

Unless your rifle is very short throated and the COAL with the bullet just off (say 0.010 - 0.020") the lands is under 2.85", I'd recommend starting at around 42.5 to 43gn, go up in relatively coarse steps to 44.5gn and then work up in 0.2gn steps from there. You may find you need a powder funnel with a five or six inch drop tube once you get up to the 44.5 or 45gn mark as you'll run a full case and very likely a compressed load at the sort of loads you'll want to use. Don't jam seat the bullets in the lands, the Juggernaut doesn't need it, and it WILL put N150 pressures through the roof.

 

[michaelnel]

I have had great results with the 167gr Lapua bullets, N150, Lapua brass and Fed 210M primers in my 28" Criterion-barreled .308. Last week I shot a 1.04" five shot group at 300 yards with that stuff. When I do my part, it shoots great.

 

[Laurie]

I have had great results with the 167gr Lapua bullets, N150, Lapua brass and Fed 210M primers in my 28" Criterion-barreled .308.

The 167gn lapua Scenar is a short-range bullet very much in the tradition of the 168gn Sierra MK with an equally high i7 'form factor' value (a drag based measure of efficiency where high is bad), and hence low BC. Such bullets often shoot very well indeed at shorter distances, the Sierra originally designed for 300M 3P discipline shooting a long time ago, and the Lapua was likely aimed at the same market, but they disappoint in 1,000 yards competition when fired at 308 Win MVs. It's this task, one that really stretches the 308 to its ballistic limits, which the OP wishes to undertake.

 

[Longone1]

Unless your rifle is very short throated and the COAL with the bullet just off (say 0.010 - 0.020") the lands is under 2.85", I'd recommend starting at around 42.5 to 43gn, go up in relatively coarse steps to 44.5gn and then work up in 0.2gn steps from there. You may find you need a powder funnel with a five or six inch drop tube once you get up to the 44.5 or 45gn mark as you'll run a full case and very likely a compressed load at the sort of loads you'll want to use. Don't jam seat the bullets in the lands, the Juggernaut doesn't need it, and it WILL put N150 pressures through the roof.

My OAL is 2.894" with this bullet, I'm using Lapua cases and my starting load is 42.0. From there I went to 43.5 in .5 grain steps, after that I worked in .3 grain incriments to 44.8.

I'm using CCI BR-2 primers and am .015" off the lands. My plan? is to shoot one of each till I get in the 2700 fps range (if I do) and then shoot at least 3 shot groups of each to get some ES and SD numbers. Most likely a second trip to the range will be needed to find the max load but I'm OK with that, still better than cutting the grass.

Thanks to all who have help guide me to this point, I will be posting my results tomorrow evening. Any other thoughts will be welcomed.

Thanks, Longone

 

[memilanuk]

I've used it in .308 and .223, with the B82BT, B155.5BT and B185 Juggernaut. From 30" bolt gun (.308 & .223) to 26" AR spacegun. Works great, final loads seem to end up pretty dang close to what I use with Varget in the same gun with the same bullet.

Current load - Berger 185s in a Sav 12 F/TR barrel (set back 0.3" and re-chambered with the 2013 US FTR reamer, i.e. 0.170" freebore) jumping 0.020" over 45.7gn Viht N150 in a Lapua Palma case lit by CCI 450 primers. MV ~2775fps. Load seems to shoot pretty well when I do my part.

YMMV,

Monte

 

[Longone1]

Made it to the range yesterday and N150 continues to amaze me with how constant it burns. The last load I loaded was 44.8 grains with a Lapua case and a CCI-BR-2 primer. The Av. vel. was 2706 while the SD. was 3 and the ES. was 8.
The group did not reflect the great numbers being only MOA. From 44.5 to 44.8 there was a 22 fps. increase so I think I should work up in .2 gr. as recommended.

Longone