Looking at powder options in a brand new Brux 6 GT. 107-108-115 dtac does anyone have any experience. What say the hoard?
Vihtavuori in a 6 gt
- Thread starter ramslammer
- Start date
No experience but from what I have read, many have success with Varget, and N140 is pretty close to Varget. I have some N540 that I want to try.
Getting a clear answer on this has been interesting. Everything from N140 to N555 has been suggested. I’m still sitting on enough H4350 to not care to try VV, but I’m so curious.
I'm very interested in this living somewhere where Varget and H4350 are now banned. N140 up to 105gr and N150 above? I'm going N140 works for everything as I have some and it is at least possible to buy more.
N150, 105gr Hybrids. 27" Krieger.
5 shot groups.
5 shot groups.
Normally I would think N540 might be a bit fast for heavies, but it seems like it’s working for people. N550 will probably give you a better velocity/case-fill ratio though. N150 will definitely save the throat on your barrel in exchange for some velocity loss, but N160 tends to be a better fit for the 6mm GT/Creed cartridges again giving you better velocity/case-fill ratio.
I thank you all for the info I think I am going to try to find some n550 and n160 and try it. With 108 eldm and 115Dtac again the Hoard come thru. THANKS
Surprised VV don't have any data out yet. I've requested some data, see what they come back with.
I will try N140 and N150 at some point when I run out of SWPR in 6GT... and whichever one seems closest to Varget/SWPR is probably what I'll be rolling with for my next couple of barrels. I don't care about max speed/MV at all and case-fill very little.
I'm a Varget/Varget-alike kool-aid drinker at this point, there's something about the faster powders that is magical when it comes to making low SDs easy. I don't think case-fill matters as much as some (incuding me) think/thought (truthfully it doesn't seem to matter at all since I started dropping every single one of my charges to the nearest kernel/flake). After shooting a lot of both, I will probably always choose the faster class of powders over the the slower for the foreseeable future (I don't worry about pressure since I'm not chasing speed).
I only run 32 grains in my 6GT (which some might consider low case fill) and haven't ever seen an SD higher than a 6 over 20 shots.
I'm a Varget/Varget-alike kool-aid drinker at this point, there's something about the faster powders that is magical when it comes to making low SDs easy. I don't think case-fill matters as much as some (incuding me) think/thought (truthfully it doesn't seem to matter at all since I started dropping every single one of my charges to the nearest kernel/flake). After shooting a lot of both, I will probably always choose the faster class of powders over the the slower for the foreseeable future (I don't worry about pressure since I'm not chasing speed).
I only run 32 grains in my 6GT (which some might consider low case fill) and haven't ever seen an SD higher than a 6 over 20 shots.
Interestingly that works fine in pistol cartridges. Most of my most accurate, admittedly low velocity, loads are light loads of fast powders. Whether that translates to rifles cartridges I don't know.
It's funny you mention that, I have noticed that it's kind of miraculous that my mixed headstamp range-pickup, cranked out at hundreds of rounds an hour Dillon bunny-fart USPSA 9mm is always low single-digit SDs... I never made the connection before, but there might be something to it?
I just have always noticed that all the 6mm cartridges that everyone always raves about being easy to load for and accurate like 6BR/BRA/BRX and Dasher always use Varget or Varget-alikes in their "classic recipes"... using Varget/SWPR in 6GT the same things seem to hold true IME.
...and while I've only tested a couple of hundred rounds of it, 35-36gn of SWPR in 6CM is/was eye-opening: works awesome!
My theory is the slower powders need a fuller case to get consistent combustion, whereas the fast powders burn so quickly that any difference in pressure is negated. The fast powders may also be less influenced by primers for similar reasons? If N140 works in 6GT with all bullet weights that would be a bonus as it's reasonably easy to obtain here.
The only downside I see is the possibility of reaching pressure before max velocity. As I'm only targeting 2850 FPS that may not be an issue.
N140 may be a bit too fast for heavies - barely 90% case fill and already approaching max pressure.
N150 is an improvement and probably the better case-fill/velocity ratio
N160 will give you more velocity with lower case-fill
And N550 will give you even more velocity for roughly the same case-fill at the expense of faster throat erosion
Vihtavuori N150 Smokeless Powder 8 lb. - Whidden Gunworks
Due to safety considerations and legal/regulatory reasons Smokeless Powder may not be returned.
www.whiddengunworks.com
I wouldn’t wait to long…
I only ran it with Berger 108 BTHPs. I used it during the pandemic to break in a barrel when my supply of Varget was limited. 33.5 grains got me about 2850 in a new Bartlien 26" barrel. It was the older version of N140 that did not have the reduced temp sensitivity.
I was reading some of the earlier comments, and looking at the Viht site, and you might be onto something about N160 being worth a try...
Its supposed lower flame temp may help with barrel life, I'm just weary of it being a little too slow to where it loses some of the magic? But it does look promising as an option closer to H4350 than Varget.
The general rule of thumb from a VV rep: use N100–series if you’re shooting rapid fire stages and want to prevent the barrel from heating up too quickly, or just to mitigate throat erosion a bit. For everything else, N500-series.
I still think N160 is going to be better optimized for the 6CM, but I don't think it will suck for the GT either. If you have a need for speed in the GT though, I'm going to guess that you'll run out of case capacity with N160 well before you eclipse the speeds you'd get with N150 or N540.
I've got 8lbs of N160 sitting here for my next CM barrel, maybe I will get into it just a bit to see what kind of velocities and accuracy I'll get with it. My 27" Krieger has definitely shown a preference for the H4350 burn rate more than it has the faster stuff like Varget. Sample size of 1 however.
I've got 8lbs of N160 sitting here for my next CM barrel, maybe I will get into it just a bit to see what kind of velocities and accuracy I'll get with it. My 27" Krieger has definitely shown a preference for the H4350 burn rate more than it has the faster stuff like Varget. Sample size of 1 however.
My pet load for my 6GT 26" 7.5 barrel
33.5gr Varget
GM205m Primer
Alpha brass
Berger 109gr LRHT
SD 4.5 -5.5 ES under 16 for 20 rd strings
FPS avg 2865
This week worked up a load with N140 because i have a bunch of it (great for heavy 223) ended up with
33.5gr N140
GM205M
Alpha Brass
Berger 109 LRHT
SD 5.2 ES 17.4 for 40 rds fired
FPS avg 2881
Same point of impact at 300 yrds
Groups virtually the same
So only difference was 16FPS
Works for me!!!
33.5gr Varget
GM205m Primer
Alpha brass
Berger 109gr LRHT
SD 4.5 -5.5 ES under 16 for 20 rd strings
FPS avg 2865
This week worked up a load with N140 because i have a bunch of it (great for heavy 223) ended up with
33.5gr N140
GM205M
Alpha Brass
Berger 109 LRHT
SD 5.2 ES 17.4 for 40 rds fired
FPS avg 2881
Same point of impact at 300 yrds
Groups virtually the same
So only difference was 16FPS
Works for me!!!
I have...IMHO N140 is to fast for the GT....N150 works really well but if case fill is a concern I only get about 80% in Alpha brass but ES's-SD's and velocities are real good....N160 would probably give a better case fill...I think my buddy @John Glidewell has been playing with N160 in the GT maybe he can chime in here with some info.
Not yet, still sitting on ~16lbs of SWPR (and have 24lbs of Varget to burn through after that).
VV 140/150 will be next. I’ll get back to you in 2026 sometime lol
I am liking N160. 37 gets me 2845 with 115 dtacs. 37 is not compressed.
Similar threads
Reloading Equipment
6mm GT Brass Alpha, GAP, and 6 GT Match Master RCBS Die Set for Sale
