(Answered) Multiple Attack Roll, Alternate Munitions and Sandblaster SPA

[zakumaru]

Regarding Multiple Attack Roll (page 175, AS:CE v5): Say I have a Hunchback HBK-4G (which have AC 2/2/- ) equipped with Precision ammo (p.145 ) and it attacks a target a short range dealing 4 damage.  Do I roll 4 times and designate 2 of the rolls as the AC attack with the -2 TN mod from the Precision ammo dealing 1 damage each? Or do I roll 3 times and designate 1 of the rolls as the AC2/2/- attack with the -2 TN mod and dealing 2 damage for this roll if hit?

Another question is regarding the Sandblaster SPA in combination with Multiple Attack Rolls: the Archer ARC-2R has LRM 1/2/2 and it's standard attack is 2/3/3. When it attacks a target at short range, can it say it rolls 2 attack rolls and have one of the rolls be designated as the LRM attack which in turn applies the effects from the Sandblaster SPA in similar fashion as with the alternate munitions? 

[nckestrel]

HBK-4G: You roll one attack roll for each point of damage (4), designating two of them as the AC/Precision ammo.

Sandblaster requires that you only use AC, FLK, IATM, LRM, SRM or TOR.  Multiple Attack Rolls does not allow you to ignore that restriction.  For your ARC-2R, you can attack with its standard damage values of 2/3/3, or you can make a Sandblaster LRM attack with a -1 target number modifier and 3/3/3 (LRM1/2/2 plus 2 at short range and 1 at medium or long for Sandblaster) damage values.

[zakumaru]

Thanks for the clarification, it all make sense. One more question though regarding the alternate munitions, this is regarding Armor Piercing which has an example on the same page (p.175). It is clear that you would need to "sacrifice" an attack roll, however does it strictly require from the AC attack? If so   it would mean that units with AC 1/1/1 must always roll for Minimal Damage even if the unit have a base attack of 4/4/4?
Also if the AC attack roll hits but the roll for Minimal Damage fails, does this mean the effect for Armor Piercing would also "fail" (ie. no chance for a crit roll)?