We have spent a vast amount of time and energy working on the 25×47 Lapua load development for this new cartridge setup. Likewise we have been constantly posting information trying to expand the data for the shooters looking to adopt it. http://Blackjackbullets.com
With hundreds of rounds down the barrel with this cartridge, we have solid performance, additionally multiple talking points. Starting with velocity, the Berger 135 Hybrid is a fast bullet. With that being said, this cartridge only opens its stride with it being ran relatively hard. Consequentially, finding the sweet spot takes finding the max pressure as a baseline.
Jump the 135 Berger Hybrid
Find the pressure zone for the cartridge with whatever you choose for a powder, then you tweak the seat depth. We found that the bullet like a jump over .100. Above are the results of .130 jump resulting in 2900 FPS. You can see that the groups on the left were doing pretty well with Atlas CAL bipods and Armageddon Gear Gamechanger rear bag. Comparatively the groups on the right row were off a prop using only a bag. Its good to see that the group size did not really change as a result.
Group Size
The scale of this target is slightly off given that the white box should be one minute of angle(MOA). It measures somewhere in the ballpark of .9 MOA just for size reference. In the end of all this work with this projectile and cartridge, we have gathered enough info to confidently get people switching over. Moreover, If you run 6.5×47, the change is easy while seeming to be worth it.
BULLET DROP WITH 135 BERGER HYBRID
Above is a range card from Applied Ballistics. Its representing a the Berger 135 Hybrid at 2900 FPS at sea level with a 10 MPH full value wind. Important to realize is the wind drift and the bullet drop. Notably the wind drift. The wind drift is on par with the best of them. 1.4 MILS of drift with a wind speed like that is impressive to say the least. Also dancing with the 7 MILS mark means that at higher altitude its in the 6 MILS range yielding not only a flat projectile but one that is forgiving. 25×47 Lapua How-To
Do you have any data for R15.5 and 135 Berger or the new 134 ELDM?
Thanks Anthony
Crown Ridge Barrel Works
If you shoot me an email at GOATVALLEYPRECISION@YAHOO.COM we can discuss this in depth. Thanks Anthony.