hi everyone, this is my first post, i've been playing a very long time and look forward to hearing from you all and getting advice about my acoustic guitars. i first question is what's the deal with bending the ball end of the string? the only "good" acoustic i ever had was a Gibson Hummingbird. back in the '90's i had an endorsement with Gibson and the would lend me stuff but that's over. now i have a Blueridge BR-140 adn i love it. i'm also having a hard time with getting the new bone pins to seat uniformly, does it matter? and if it does how do i fix it?
You bend the ball end slightly to make it clear the end of the pin more easily and seat against the bridge plate better, that's about it. I generally round over the end of the pins slightly too when I first get a guitar, though some come this way. I prefer ebony (or other hardwood) pins. Either way, it's not a big issue and you don't have to do these things if you're otherwise careful.
Check to make sure your bone pins are the right taper for the holes, they should match. If they are, then it may be an issue with the pin slots, or the slots at the top of the holes, or the bevels at the top of the holes.
As far as seating the pins uniformly, you can use some 400 grit sandpaper and go slowly sanding each from the skirt down to fit. It doesn't take much sanding at all usually so only take off a little at a time and test frequently for fit. I would then use a fine Sharpie to label each near the bottom as each one will be "custom fit" to the corresponding hole. When you re-string you do also have to pay some attention to the pins as they otherwise have a tendency to float up a bit in a non uniform fashion while tuning up. If after this they're still seated non-uniform as long as they're not about to "fly" out I wouldn't worry about it. At the end of the day, I think it's really esthetic as everything is held in place with tension anyways. Definitely don't press down on them if they are popping up with any force once under tension as you don't want to potentially crack the bridge!
All the best,