Has anyone experimented with removing the radius where the base meets the boat tail by turning on a lathe or grinding the base of a bullet? I was looking for anyone that had reproduced the “square heel experiment” presented in Bryan Litz’s Modern Advancements in Long Range Shooting. I am interested in performance gains to the form factor or BC with regards to the current crop of heavy 7mm match bullets (183 SMK, 195 Berger EOL, 197 SMK). If anyone is willing to share their experience I would appreciate it, I will share what I observed today. I tried it out a limited test today with the 7mm 180 Hybrid and recorded velocities at the muzzle, 100 yards down range (Lab Radar) and 1000 yards (Shotmarker acoustic target). While the results were less than expected, I was hoping to get a 2%-4% increase to the form factor of the bullet and observed approximately 1.2% increase. This was a very limited test as I only tested 9 modified bullets against a control of 11 unmodified bullets. All 20 where all presorted by base to tip length and all were (1.528-1.529) inches an effort to uniform BC (the bullets were not pointed or trimmed) . The modified bullet’s bases were ground flat removing the radius edge and approximately 15 thousands from the base to ogive, this was also 1.26 grains of copper (178.74 down from 180). The test was shot alternating between the control and modified rounds and the difference between the modified and control average velocities at the three ranges were as follows: CONTROL: 0 2862.8 100 2734.8 1000 1618.9 EXPERIMENT: 0 2869.556 100 2734 1000 1622.778 Difference: 0 6.755556 100 -0.8 1000 3.877778 If my math is right I believe this is a BC of .310 for the control (180 grain) with a 1.028 form factor and a BC of .3115 with a 1.016 form factor for the experimental group (178.74 grain) Conditions 82F 13% Humidity 29.3 Barometric The difference is so small it could be simply be chalked up to experimental error in the variance from the chronograph, but I figured I would throw out the results because there does appear to be a weak effect from squaring the base of this particular bullet. And I was interested if anyone else had ventured down this path with 7mm bullets and found any interesting gains.