I think it has to do with the bullet getting distorted or canting in the worn barrel in the Luger, and when the powder is slowed down the bullet has a better chance of starting on the right track and engraving into the grooves better. But that's a guess too. I am trying to figure out how I can test a couple of theories to try to find out what is going on.
I know one thing, that this is not just isolated to a luger and red dot, but all loads are affected somewhat by powder burn speeds and also plated bullets might be more susceptible to distortion than plated...but again, that too is a theory and needs to be tested.
I like some of the testing methodology in the book Rifle Accuracy, and how he exaggerates certain issues to prove his theories. the guy really debunks a lot of reloading dogma rather quickly.
|