diff --git a/ace_advanced_ballistics.dll b/ace_advanced_ballistics.dll
index 1af3d8ca3c..09b93a543f 100644
Binary files a/ace_advanced_ballistics.dll and b/ace_advanced_ballistics.dll differ
diff --git a/extensions/advanced_ballistics/AdvancedBallistics.cpp b/extensions/advanced_ballistics/AdvancedBallistics.cpp
index 7e4a537678..32955b4316 100644
--- a/extensions/advanced_ballistics/AdvancedBallistics.cpp
+++ b/extensions/advanced_ballistics/AdvancedBallistics.cpp
@@ -681,7 +681,9 @@ void __stdcall RVExtension(char *output, int outputSize, const char *function)
 
         if (TOF > 0) {
             double bulletDir = atan2(velocity[0], velocity[1]);
-            double spinAccel = bulletDatabase[index].twistDirection * (0.0482251 * (bulletDatabase[index].stabilityFactor + 1.2)) / pow(TOF, 0.17);
+            double r1 = pow(TOF - deltaT, 0.17);
+            double r2 = pow(TOF, 0.17);
+            double spinAccel = bulletDatabase[index].twistDirection * (0.0482251 * (bulletDatabase[index].stabilityFactor + 1.2)) / ((r1 + r2) / 2.0f);
             velocityOffset[0] += sin(bulletDir + M_PI / 2) * spinAccel * deltaT;
             velocityOffset[1] += cos(bulletDir + M_PI / 2) * spinAccel * deltaT;
         }