So friends and I are new to D&D and we were wondering about how some class mechanics would mix together...
Could a Wizard archetype Spellslinger multiclassed with Magus archetype Myrmidarch use ranged spellstrike with a pistol/revolver, and if so could that character then perform a full-round action using the ranged spellstrike and whatever other normal attacks with the pistol(s) they could?
More general question: could a wizard with a high int ability cast spells higher than they could through class spells per day (via gaining higher level bonus spells from Int)for example could a level 4 wizard with 22 intelligence cast a 3rd, 4th, 5th or 6th level wizard spell?
For being new to D&D, you're certainly jumping in headfirst. Normally I'd just suggest picking a base class and running it vanilla.
A myrmidarch can certainly deliver magus spells through a gun. However, the spell-delivering attack comes in place of the free ray attack you normally get when casting a ray spell. Casting the spell is (usually) standard action, so that's the only attack you get.
Normally, a magus uses spell combat to get the sword+spell+touch combination, and this stacks with spellstrike to give sword+spell+swordtouch. Unfortunately, spell combat is limited to melee weapons, even for a myrmidarch. So you're out of luck there. Spellslinger doesn't really change things at all.
As for spellcasters casting higher level spells than normally available: nope, sorry. You don't get the bonus spells until you qualify for those spell levels. So no level 4 disintegrates for you.
You might want to talk with your DM about letting your Myrmidarch have the gunsmithing feat and a beaten up firearm at 1st level like gunslingers. That could work too.
As to your first question: Yes, it's a ranged weapon so it could work.
Second: No. They just get bonus spells when they are able to cast that level of spell