when i started bowling a year and a half ago, i was using 14lbs equipment. after learning how to bowl and what not, i decided it was time to move to 15. i ended up trying to go with no finger inserts as well and felt i was throwing the ball great. then i realized that i was coming out of the ball flat and my ball would just roll out. my pro shop guy then suggested i go with finger inserts so i can stay in the ball longer and get more lift. it worked for a while, but i still never was able to come around the ball as i used to with my 14lbs equipment. i thought it was the different release i got from bowling with no inserts and getting some coaching from another coach then my usual one, but when i went back to my old way, i would still come out flat.
i went out to practice today and for the hell of it, i took out one of my 14lbs balls. got an hour and for the last 15 minutes i pulled out the 14lbs ball. i noticed immidiately that i had a way better roll on the ball and the ball reaction was amazing! i never hooked the ball that much since i started! i knew the guy there so he let me bowl another 30 minutes free and i kept throwing balls. i threw my 15lbs stuff after and it would roll out again. same ball, same layout, same surface, everything! i wanted to same reaction so i got the same ball in 15 after moving up.
after this long story, my question is, would the weight be a big factor? its not that i cant keep my speed up with a 15lbs ball, i still throw it around 15-16mph. i sold most of my 14lbs stuff, but still kept a couple for sentimental reasons. good thing i did cause i brought them all back out for the next time i practice.