That's sort of why I included the possibility of a detonation right out of the barrel. From a narrative perspective, they'd continue to make sniper rifles and grenade launchers because of the inherent instability of compressed plasma. Satchmo points out a point I need to consider, however, in that someone with 3 Brawn (to satisfy the Cumbersome rating) will likely Soak most or all of the damage. I mean, with a 1 in 12 chance of an Engaged detonation on an upgraded roll, you're taking your health into your own hands, but that doesn't mean much if you don't have any chance of taking damage.
Maybe a better solution would be to give it the Concussive property, rather than Blast damage. That way it's still only affecting the main target, but it does have that something extra without overpowering the weapon. I'm also exchanging Prepare 1 for Slow-Firing 1. How does this compare, in your opinion, to the E-11s?
LR-42 E-11s
Damage 10 10
Critical 3 3
Range Extreme Extreme
Encumbrance 6 6
HP 3 3
Price 3750 (R) 3500 (R)
Rarity 7 7
Special Accurate 2 Accurate 1
Cumbersome 3 Cumbersome 3
Concussive 2 Pierce 2
Slow-Firing 1 Slow-Firing 1
Essentially you're exchanging Pierce 2 for an extra point of Accurate and Concussive 2.
Edited by Simon Retold