Load Mapping

[broncman]

With all the load development threads and ideas I decided to collect as much data as possible and enter it into some Excel spreadsheets to make it easier to compare.

I loaded some 308 Berger 215 Hybrids in brand new out if the box Lapua brass, Tula primers and Varget powder. Loaded up 4 powder charges at 3 different seating depths for each charge. 5 shots each.

I will post up the target pics and graphs. This was very interesting and learned a lot but it raised even more questions.

One very interesting fact was at higher case fill densitys of the same charge, velocity DECREASED as I got near the lands...INCREASED with the lowest charge weight?????

So, off to enter in all the data

 

[broncman]

Got all the data in and some charts that show some very intereting trends in the data!

Can anyone tell me how to post up the charts so they can be viewed? Some kind of file conversion that can be viewed in the post?

 

[broncman]

Ok, got Excel figured out...
This one tracks velocity by charge weight and seating depth.

 

[broncman]

And extreme spread fps by seating depth . Interesting info. Going to try higher charge weights as pressure signs were still ok.

 

[broncman]

After looking at the charts, you can see the node that seems to revolve around .010 seating depth and 2450 FPS, so I loaded up 5 at 41.8 gr and 42 grains to see if their was a large sweet spot . Here is the 41.8

And the 42 gr. Their is some recoil to deal with but these loads look real good.

 

[broncman]

After a pm from a forum member I decided to try 43.2 to get to a higher speed node. The current speed of 2450 gives me little advantage over the juggernauts. I loaded three to check for pressure signs and used once fired, neck sized cases. Very promising. For these 3 loads, es was below 10. Not sure if it will hold that for more shots but looks promising.