The Firing Line Forums - View Single Post - caseless ammo... could it really be that easy ???

briandg · April 12, 2012, 08:05 AM

it is conceivable that something could be created with solid propellant extrusion. A projectile could be created with a spud on the back that would be friction fit into a hollow in the solid propellant cylinder.

We make extruded propellant used in artillery that is quite a bit like polyurethane in nature. so, create a cylinder of this. use a bullet of like diameter, like a pistol round. Bolt face should have a heavy blasting spark plug, just like a car plug, that would send an arc of at least 1/8 inch across the base of that propellent slug, igniting it at the base, and letting it burn just like a rocket would.

Tapered bolt with high temp o rings, a solid push into locked battery, and a shroud would be mandatory. The shroud should capture any leakage, and there obviously will be leakage, and expell it forward through a channel under the barrel.

Setting the thing up as a rocket propelled type cartridge that would burn front to back instead of a fully involved powder charge would allow pressures to remain more constant chamber to muzzle, and hence, lower.

I am also picturing it as a semi auto, gas operated, with a reciprocating action. like the old steam engines.
A charge of bled off gas blows bolt out of battery. When the bolt reaches full extension backward, a bolt return spring is assisted by the same gas that opened the action being vented into a system that forces it back forward.

There are ENORMOUS problems with this. One of the biggest problems I see are that the caseless rounds are absolutely not safe around heat sources, and are going to be incredibly fragile.

But, bottom line, imo, is that without solid propellant charges and reliable electronic ignition, this is impossible. You also have to find a way to seal that chamber against 20k psi shot after shot. There's no way to do that, I don't think, that will be better than just staying with the good old metallic cartridge.

April 12, 2012, 08:05 AM	#14
briandg Senior Member Join Date: May 4, 2010 Posts: 5,468	it is conceivable that something could be created with solid propellant extrusion. A projectile could be created with a spud on the back that would be friction fit into a hollow in the solid propellant cylinder. We make extruded propellant used in artillery that is quite a bit like polyurethane in nature. so, create a cylinder of this. use a bullet of like diameter, like a pistol round. Bolt face should have a heavy blasting spark plug, just like a car plug, that would send an arc of at least 1/8 inch across the base of that propellent slug, igniting it at the base, and letting it burn just like a rocket would. Tapered bolt with high temp o rings, a solid push into locked battery, and a shroud would be mandatory. The shroud should capture any leakage, and there obviously will be leakage, and expell it forward through a channel under the barrel. Setting the thing up as a rocket propelled type cartridge that would burn front to back instead of a fully involved powder charge would allow pressures to remain more constant chamber to muzzle, and hence, lower. I am also picturing it as a semi auto, gas operated, with a reciprocating action. like the old steam engines. A charge of bled off gas blows bolt out of battery. When the bolt reaches full extension backward, a bolt return spring is assisted by the same gas that opened the action being vented into a system that forces it back forward. There are ENORMOUS problems with this. One of the biggest problems I see are that the caseless rounds are absolutely not safe around heat sources, and are going to be incredibly fragile. But, bottom line, imo, is that without solid propellant charges and reliable electronic ignition, this is impossible. You also have to find a way to seal that chamber against 20k psi shot after shot. There's no way to do that, I don't think, that will be better than just staying with the good old metallic cartridge.