Yeah, why not? Even if the railgun described was perfectly vertical, it would have 20km of length (vs presumably ~10m max for a military railgun that hits mach

Yeah, why not? Even if the railgun described was perfectly vertical, it would have 20km of length (vs presumably ~10m max for a military railgun that hits mach 3+). If I'm doing the math right, at 20km of length you need an acceleration of about 160 Gs to reach 8 km/s over that length. Survivable for some payloads. If the railgun is sloped at a 1% grade, it has ~2,000km of length. On that track, a comfy 1.6 Gs of acceleration for 500 seconds gets you up to 8 km/s.