Duplicating Lapua 338 factory 300g Scenar Ammo

[stuntpilot]

The first two groups at 100 and 200 yds out of my new DTA SRS 338 using Lapua factory loaded 300g Scenar rounds looked like this:

If they weren't $6 each, I'd skip working up loads all together and stick with what's working. I took apart a couple of the factory rounds when I got home. They had 91.3 grains of powder in them. From comparative burn rate, I'd hypothesize H1000 or VV570 would be closest to what the factory was using (although neither looks precisely identical in a side by side view, nor did Retumbo or RL25). Has anyone managed to duplicate the factory load over a chronograph and mind sharing?

I've worked up some loads I intend to test with a chronograph in H1000/VV570 across propellant weights of 91.0, 91.5, 92.0, and 92.5g over F215M primers. I'll share the results here when I'm done. Just curious if I was re-inventing the wheel, or if someone had better insight into the components?

Thanks in advance,
Stuntpilot

 

[turbo54]

Re: Duplicating Lapua 338 factory 300g Scenar Ammo

Lapua ammo uses custom-blended Viht powder not commercially available to hobbyists like us.

 

[Jeffvn]

Re: Duplicating Lapua 338 factory 300g Scenar Ammo

+1 Lapua factory ammo uses a powder that you can't buy off the shelf.

Did you chronograph the load when you shot it? You can expect similar results from your hand loads if you can match the velocity, ES and SD numbers.

JeffVN

 

[stuntpilot]

Re: Duplicating Lapua 338 factory 300g Scenar Ammo

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Jeffvn</div><div class="ubbcode-body">Did you chronograph the load when you shot it?

JeffVN </div></div>

Tested from my DTA SRS 338 today in 101 degree central Texas heat with winds S15G23. Groups are 5 shots at 200 yards.


Powder Bullet Average Velocity SD Group at 200yd
Factory loaded Lapua 300 Scenar 2641 22 0.934"
91.5g VV 570 300 Scenar 2634 11 0.579"
91.5g H1000 300 Scenar 2758 25 0.717"
91.5g H1000 300 Berger 2580 19 1.624"
91.5g RL25 300 Scenar 2798 23 1.301"

Will be doing some more work on the VV570/300Scenar combo, but we're already "close enough" in my book.

 

[Jeffvn]

Re: Duplicating Lapua 338 factory 300g Scenar Ammo

Yep the 570 looks like a close match to what you were looking at. If you back down the H1000 a touch it might give you a good match also.

You may want to try Retumbo, but if you like the VV570 and H1000 there is no reason to keep experimenting...

Here in Vegas, its too hot to even consider RL-25, at lest in my rifles, but my 7WSM loved it when I lived in Houston.