6.5 Grendel CAD - FEA

[cory]

If I were you, I would consider just cutting a piece of Grendel brass in half longitudinally, taking a picture of it, and making your CAD file that way.

What would be very helpful to the forum would be if you compared Lapua, Hornady, Wolf PPU, 7.62x39 Federal, Lapua, Winchester, IMI, etc. necked-down to Grendel. The members here could provide you with samples of everything you don't have brass-wise.

You would also want to do a hardness analysis on all the samples, as they aren't the same. Lapua brass has the best longevity.

I found some dimensions for the Grendel, but I'm not sure how accurate they are.

http://www.6mmbr.com/cartridgediagrams.html

If it is correct all I'd need to do is cut some brass in two and measure the material thickness. I've got Hornady and Lapua Brass I could measure, if someone could provide me with the measurements or the other brass itself. Any suggestions on how to best cut brass in half without damaging it more than necessary?

I don't have the resources for a hardness analysis at this time. If someone here does and could provide the data, it would be much appreciated.

I could model the brass in SolidWorks. I would need someone to supply external and internal dimensions. Meaning full results will be tricky as the material properties are different at the head and neck do to annealing. It would be interesting to check if case stress would be different in max and min chambers due to varying deformation. Simulating the "belted magnum" affect due to early extraction would be cool too.
Sorry to ramble and pull big words out of the air. It has been a long time since I took an FEA class. Good luck.

dmsims21 welcome aboard! If you had time to model it that'd be great, if not I'm sure I'll find time to do it.

Could you elaborate on the "belted magnum" effect?

I intend to do my initial analysis at the instance before the bolt releases, with the assumption that pressure is the highest at that point in time. I may continue it introducing more variables as I go, if it appears further analysis is useful/necessary.