I was going to order my first load of cast bullets and a friend said only use the ones lubed with blue lube but my research has shown that about 90% of suppliers bullets have red lube so I'm wondering if my friend knows what he's talking about

Never knew there was difference... some bullets are lubed for the use with black powder but the black powder lubed bullets work with smokeless powder too. I wouldnt worry about it

Good cast bullet lube can be almost any color. However, there is one made by LBT (Lead Bullet Technologies) Company called LBT Blue, and this lube will prevent leading while allowing you to get velocities over 2700 FPS (with cetrain bullets & alloys) with bullets you cast yourself! I know of no source for ready-made bullets with this ability, but there may be some.....

Maybe your friends were referring to LBT Blue?? If so, they're correct!

I never knew there was a difference either. My friend sold his 44 and gave me about10,000 240 gr cast bullets all with the blue lube. I loaded a counted 1000 and it didn't look like I even dented the quantity.