Tony Williams Wrote:In principle I like the idea of a very aerodynamic jacket with a hardened steel core (with a blunt penetrating point) set back inside the jacket, with either an air space or lightweight plastic tip filler. This should yaw readily on penetration of a soft target and also penetrate hard targets. The main problem would be getting enough weight into the bullet to achieve the ballistic coefficient needed for long-range performance...Hmm... it does appear that way. If I figured correctly, scaling up the 5.45mm bullet to 6.5mm would result in a projectile weight of only 90 grains!
Quote:Tungsten is technically the ideal core material which would make all this possible, of course, but for the cost!Cost is not the only problem. Tungsten was eliminated by the US Army from use as the slug material early in the development of lead-free M855, due to environmental concerns (heavy metal pollution). One might think the same restriction would be in Europe, too?
Quote:There is obviously a trade-off between weight and shape, in that the more aerodynamic the shape, the lighter the bullet can afford to be for any given BC. Maybe we should take a look at the 5.56mm FABRL and the light-alloy and plastic cored CETME bullet designs, and start from there. After all, if the CETME bullets showed a good BC with a light-alloy core, then we should surely be able to do better with a steel core.Several years ago I discussed the FABRL and CETME with Frank Hackley, who said:
[COLOR="blue"]"The long pointed streamlined bullets did have a number of short comings. First, terminal ballistics [i.e., helmet penetration] were never achieved, primarily because of the bullets light weight. Second, it was assumed that the bullet's armor-piercing ability would be limited because of the shape. And finally, the FABRL bullet made a very poor tracer.
I do not know very much about the CETME, but would not be surprised if some of the same problems prevailed with this round too.
However, there were designs made with the AR-2 shape which included bullets made from copper coated steel and given limited testing but I do not have the test results."[/COLOR]