On-Line Velocity Estimation

[JASmith]

I just posted a tool for helping folks estimate muzzle velocities when their loads involve different barrel lengths and reduced loads compared to existing load data:

http://shootersnotes.com/calculator/velocity-estimator/

The estimator is effectively a modest extension of the Powley calculator. It allows you to use your powder even though it might not be one of the IMR powders the Powley calculator was built to handle.

The method was calibrated with jacketed bullets. Folks have, however, pointed out that it may work with cast bullets and, possibly, black powder. I am curious about how well the method might extend into this arena.

To use the tool, you will need to enter a reference load that uses the same powder but with a charge weight equal to or greater than the one you use in your load. Same for the bullet, it will need to be the same weight or heavier than the one you use and more likely even better if its the same brand. Barrel length for reference load is needed along with your barrel length.

Let me know how it goes!

Thanks!

[versifier]

Welcome to the Guide.

Thank you for the link. Interesting, but there is still no substitute for running the load over a chrono and measuring the real numbers. No simulation can be relied upon ever to give more than a general idea of what actually happens in the real world. Differences in components and the interior finish of barrels all add variables that are impossible to simulate or calculate. After years of loading cast and playing with wildcats I have come to the inescapable conclusion that there is just no substitute for loading up a few rounds and actually testing them. Some formulas do come fairly close sometimes, and I will check this one out come spring when I start testing seriously again, but that is always for me an after the fact observation when I am going over my chrono data and planning the next tests to run.