I use that chute as a drogue on my 4" Jart and it's perfect. Drops straight down with enough drag to hold the nose above the body.
My Jart probably weighs close to what your Magnum does, but the sectional density is much higher. You may want a slightly larger drogue.
My Jart probably weighs close to what your Magnum does, but the sectional density is much higher. You may want a slightly larger drogue.