Home Forums Reloading Reloading Software Another Free Upgrade

I was playing with ballistic explorer this weekend and found another free upgrade was available. This time they've added Spin drift and Coriolis effect, but also included a bullet length estimator and a bullet stability and twist rate calculator that open right from the trace window. They've also added over 300 bullets to their database and now all the bullets have lengths, even for loaded ammo. Must be close to 5000 in there, but many are estimated lengths. Got this image from the website.



Wondering how good the estimates are I dug out a bunch of old bullets I've had for many years that aren't listed in any database I've found, so I figured I would use them to test the claim that the bullet length estimator is accurate to within 1/3 caliber over 92% of the time. What I found is that it was even more accurate on 8 of the 10 bullets I tried, being within 1/4 caliber. The only bullet that was outside the 1/3 caliber was a hunting type I considered round nose, but with that selection it was about 1/2 caliber off. When I selected semi-pointed for the bullet shape then the estimated length was with 1/3 caliber. Overall I found the bullet length estimator is accurate, but with some margin of error in selecting the bullet's shape from a dropdown list of 9 shapes. That said, I know of no other such tool be it on a website or in an app.

How useful it is depends on how much you try new bullets and loads. Many bullet manufacturer websites list bullet length now, but some still don't, so I can now use the estimator to get a good idea of a bullet's length. For loaded ammo few manufactures publish length figures, so if I want to check if a gun has enough spin to stabilize them I have to buy a box and pull a bullet, or use this handy estimator, even before I buy a box.

http://www.jbmballistics.com/cgi-bin/jbmstab-5.1.cgi

Has 98% of all bullets measured and test numbers from Litz.

I've used JBM, but it's torturous using a web interface after working in Ballistic Explorer's Windows® interface. Also, Ballistic Explorer has many more tools, and gives me estimated lengths for any bullet including loaded ammo. Of course, it's not free, but I've always found paying for good tools paid off in time.