308 load

[20series]

In my old pss set up i used to run 46 gns of Varget with a 175gn sierra match king.

My current set up is using 46gns of Reloder17 under a 200gn sierra matchking


Alan

[Alpha1]

155G A MAX with 43.2grains of N140 works for me.

[ovenpaa]

From the Vhit data - the max load for both (and also the 'accuracy load' quoted for 170s) 155s and 170s gives around 2700 fps...but the factory RUAG 155gn velocity is more than 2900... :-P

The Lockbase is 170 grains so more weight and it can be pushed quicker, I ran them at 860m/s (2820fps ish) through a 24" barrel. A 170LB at 2800+ is going to be every bit as good as a 155 at 2900 and I found them very accurate when they were used at longer distances.

There was however an odd problem which may have been specific to my rifle (Nothing dangerous!!) So I do look forward to hearing how Meaty gets on at 1000+

[Dougan]

[/quote]The Lockbase is 170 grains so more weight and it can be pushed quicker, I ran them at 860m/s (2820fps ish) through a 24" barrel. A 170LB at 2800+ is going to be every bit as good as a 155 at 2900 and I found them very accurate when they were used at longer distances.[/quote]

I would experiment with different bullets, but want to make a practice round that is as close to the RUAG as possible (as it's what would be issued in some comps I'd like to try) - I've got plenty of RUAG brass, and will use 155gn SMKs, so that's 2 of the same components - And I was hoping to use VN140 for convienience (as same as .303), but to match the velocity of the RUAG you may have to go beyond the max recommended load...?

I also had a look at the Vhit loads for 6.5 x 55 - It stops giving them for N140 after the bullet gets heavier than 130gn...and I have to confess I don't fully understand why...

I thought I was getting the hang of loading, but it's getting confusing again ... will have to read up about the hows and whys of powder choice :-P

[DaveT]

The usual reason for 'dropping' a specific powder after a given bullet weight in the calibre concerned is that it is considered too fast burning for the heavier bullet and you need to go to a slower burn-rate powder to keep pressures sane and still get reasonable velocity.

[Dougan]

The usual reason for 'dropping' a specific powder after a given bullet weight in the calibre concerned is that it is considered too fast burning for the heavier bullet and you need to go to a slower burn-rate powder to keep pressures sane and still get reasonable velocity.

Thanks Dave - That makes perfect sense

[DaveT]

BUT.. might also be that they simply haven't tested that Bullet / Powder combo yet!

[rox]

...but the factory RUAG 155gn velocity is more than 2900... :-P

...what would be a good accuracy load for the same powder (V140) and distances, but with a 155 SMK?

In order to get the Sierra 2155 (the bullet in the NRA RUAG ammo) to arrive at a 1000 yard target at above transonic speeds it is generally considered that it needs to exit the barrel at a minimum of 2900 to 2950. To achieve this using N140 I use 45.5 gr (30" 1-in-13" barrel, Fed GM210M primer, 0.015" jump), and this has worked well from freezing up to 46° C / 115° F.

A recent series of measurements with this load at about 13° C gave the following velocities:

2980, 2980, 2977, 2977, 2976, 2958

A friend of mine uses Rem 9 1/2 primers and 45.8 gr N140, same barrel, and obtained the following velocities at 22° C:

2962, 2975, 2956, 2967

Some recent RUAG velocity measurements (at 22° C):

2994, 2974, 2994, 2940

IIRC, when I measured RG 'Comp' (155gr) recently it was pretty close to 3000.

Of course, what works for me may not be suitable for you, so work up and follow safe practices.

..

[Dougan]

Nice one Rox - excellent info

From the comments it does look like you have load at the maximum with N140 to shoot 1000yds - but obviously I'll work up to it carefully, and see how it goes...