What is the stated twist rate of the 8.15x46R in Aydt rifles.
No, I haven't measured mine and can if no one knows the answer off the top of their head.
Purpose:  I am preparing loading data to shoot the new Alliant 300-MP using the Powley Calculator.  Velocity is a variable input in the formula based on bullet factors to generate if the loading data is within the perimeters of the known twist rate.

In the other Powley calculator, plan to use the SAMMI 32-40 CUP of 30,000

Thanks for Looking!

You know how you have an itch and have to scratch it?
Went to the basement put the rod in bore, marked the rod and the twist is 1:15 ... measured 3 times
Fired up the Powley Stability Cx and determined for a 1:15 twist:
BACO 316180, cast Dan's 3:7 at 181gr
Min - Max fps = 1125 to 1129
Stability Factor = 3.22.  A factor > 1.5 is maximality stabilized 
Bullet length Cx to 0.930 for maximum stability ...and the BACO bullet is 0.930!  
This program is an excellent tool.  When I got the mold remake of the Ideal 375166, puts the numbers in the program, calculated the min-max velocity (black powder), took the reloads to the range and shot less MOA at 100 and 200 and a little over MOA at 300yds 

OK, now to the the Powley Interior Ballistic Calculator to determine the closest exact Alliant 300-MP powder charge that has a burn rate a tad slower than H-110.  Believe the charge will be a little more than 12gr.  Cause I cheated.  Back in February I ran 4 different charges over the chrono.  Twelve grains averaged 1214 fps and produced the best group of the 4 different charges using this BACO bullet  

Thanks for looking and hope this information is beneficial to the ASSRA members and Schuetzen shooters

Confirming Frank's recomendation: I have been using 14.5 grn of 4227 with the 175grn stop-ring bullet for some years now---it works.
Fred

Joe, if yours is 14and Frank's is 14.5 twist ... even though mine came out 15 ... may be prudent for me to measure again