03-03-2014, 09:56 PM
Polymer cases have better thermal efficiency than brass?
I saw a very interesting statement recently from someone who is fairly well-known in the alternate caliber market (.458 SOCOM). Basically, the guys working on propellant technology are light years ahead of what is commonly available. The claim was made that the 5.7x28 case was lengthened and out-performed .223 Remington using these new propellants.
I haven't seen any verifying data, but it isn't outside the realm of probability. I have my own ideas of different propellant geometry for existing metallic cartridge designs, that would stage different burn rate mediums in the case for optimum pressure curve, without spiking pressure, while keeping it higher down bore.
It would be interesting to play with these in the .221 Fireball case with a 6.5mm.
I saw a very interesting statement recently from someone who is fairly well-known in the alternate caliber market (.458 SOCOM). Basically, the guys working on propellant technology are light years ahead of what is commonly available. The claim was made that the 5.7x28 case was lengthened and out-performed .223 Remington using these new propellants.
I haven't seen any verifying data, but it isn't outside the realm of probability. I have my own ideas of different propellant geometry for existing metallic cartridge designs, that would stage different burn rate mediums in the case for optimum pressure curve, without spiking pressure, while keeping it higher down bore.
It would be interesting to play with these in the .221 Fireball case with a 6.5mm.