"An improved version of N150, similar in burn rate to 4350, RL-15 and H414. Clean burning and velocity increases of 100-200fps" as advertised on the specials at www. sinclairintl.com Maybe this powder as been discussed before on this board before but what is your opinions on this powder? How is the thermal stability?

If you mean by thermal stability whether it is temperature tolerant or not, it isn't any more than any other double base powder. Certainly not in the same league with Hodgdon's Extreme line. I've used the N500 series powders and they've worked pretty good for me but I have yet to find a rifle that preferred them to other powders.

N550 is good but I get better groups from
N150.

I have found that N550 gives me the highest velocities and best accuracy in my 308 Win (165gr Partition), 338-06 (210 gr Partition) and, most recently, a 9.3x62 (250 gr Ballistic Tip and 250 gr Barnes X). I really like it.

I am in the middle of doing some load development on a 270 Win. VV doesn't have any published data, nor does anyone else, so as soon as I come up with a Chronograph I will be getting some data.
After that I am going to put together some 30-06 loads and 7.62x54r with the N550

DV

if you email VVn they will send you 270win data with N550 but i have had vary dismal results with it in the 270. ES of over 100fps and shotgun patterns.
I have found it to shin in 260rem and 7mm08
burn rate is on the fast side of 4350 much more like H380 for me.
N560 works great in the 270 or just about all other 06 based cases.

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born on a mountain, raised in a cave, hunting and fishing is all i crave!

I load 59 grs of N560 in my 24" Rem 721 270 Win in Winchester brass with the 130 gr Partition. It goes 3160 fps and averages 3 shots in .8".

Seems to me I also remember reading somewhere that the "High Energy" element (whatever that is)deteriorates over time. I can't recall where I read it though. FWIW - Dan

Thanks to all,
I think I'm going to stay with Alliant and Hodgodon. sure-shot

I buy large quantities of whatever is one sale. I bought some H-380 a few years ago for $2 a pound, got WW452 for $5 a pound, and Norma N202 and MRP for $8.

I know the Brits use N-550 in their .308's in what they call "Match Rifle" competitions. They get good results with N-550, 210gr Bergers and their 34" barrels @ 1200yds. spock

Hay Ed, what's your .308 load with N550 and the velocity? I've used 46.5 of RE15 with moly Hornady 165s and get 2950 fps from my 700 VSSF. I was thinking of changing this coming hunting season to get a little better group. The only problem with my load is that it is compressed. I've got to trickel each case by hand and then tap to get the powder down to the base of the neck.

It is my 35 whelen ackley's favored powder, pushes a 250 gr a-frame 2700 fps from the 24" barrel.

It seems to work as advertised.

It is a good compact powder. It gives best velocities in my .338-06 Acl. Imp. Never tried N-560. Some more mussle-blast is noticed by some users, but it burns really clean.

A reputable rifle maker in England reports a good friend halving his 308 match rifle barrel life (from 4k plus to 2k) by switching from VVN150 to VVN550. It is more expensive, less clean burning and produces a bit more muzzle flash.

I have used it with satisfactory results in 6.5 x 55. However, I would describe muzzle flash as substantially increased. In low-light conditions - dawn/dusk - you would be blinded by the flash.

Fine if you like doing an impression of the "A-Team" but otherwise not very practical.

Patrick

I am looking around for some 550. Looks to me that this powder works best in long barrels 24"+.