better to ask than do something dumb

[Bassfish1952]

Note: the difference in length of the test barrel between the gas gun data vs the bolt gun data. If all else were equal in terms of barrel length. The Gas gun lower pressure loads may not be giving up quite as much velocity as may first thought. Barrel length is a factor in velocity as well.

So with the all metal GMX or CX bullet it is lighter weight or the bullet is to long for chamber compared to like a ELD-x 

So I need a GMX with a tungsten center to have a 103gr bullet without a lead center that retains energy down range ?