Powder Question

15 November 2008, 03:56

1894mk2

Powder Question

Is there a double base non ball powder that is slightly faster than RL15 or Varget?

My moderated 7mm08 gets considerably louder once 40gr is exceeded.

I'd like to shoot 120/130gr bullets as quick as I can with no more than 40gr of powder. There seems to be a bit of a gap.

15 November 2008, 04:09

vapodog

IMO all alliant powders are double based....there may be others but Rl-12 is slightly faster burning.

///////////////////////////////////////////////////////////////////////////
"Socialism is a philosophy of failure, the creed of ignorance, and the gospel of envy, its inherent virtue is the equal sharing of misery."
Winston Churchill

15 November 2008, 05:32

swheeler

VV N540 is double based extruded and somewhere between RL15 and varget in speed.

15 November 2008, 06:38

308Sako

I do believe that I understand your question, but:

Isn't muzzle pressure the causative agent for the sonic issue you are attempting to address?

15 November 2008, 16:51

vines

why do you need to have double base.?? i mean, i really like RL-15 IN MY 7-08,.. but, 4064 gives me the same results.. if you need something faster you could get some 3031, 4320 or 4895. but these are single base.

15 November 2008, 19:06

unique

I suspect louder is a function of muzzle pressure more than anything. My approach would be to use Quickload program to show muzzle pressure versus velocity for a host of powders.

15 November 2008, 21:06

amamnn

According to Lapua/Vihtaouori's burn rate chart N540 is the same or a tiny bit SLOWER than RL-15. N 135 would be more in line with what you asked for though single based and is one of their rcommended powders for your load. Their faster double base, N530 is nowhere recommended for that cartridge in their manual.

17 November 2008, 01:48

1894mk2

quote:
Originally posted by amamnn:
According to Lapua/Vihtaouori's burn rate chart N540 is the same or a tiny bit SLOWER than RL-15. N 135 would be more in line with what you asked for though single based and is one of their rcommended powders for your load. Their faster double base, N530 is nowhere recommended for that cartridge in their manual.

Reccomended would be to minimise the risk of pressure excursions and to maximise velocity in standard length barrels. Minimising noise in short barreled moderated rifles is somewhat specialist!

There really does appear to be a gap.

For those who asked I've found double base powders to yield slightly more velocity.

I am sure muzzle pressure is an issue but so is charge weight and burn rate. Charge weight seems to be the most noticeable difference.