Would this work?

[Pie Guy]

I recently got complete mage.
After having a look at abjurant champion, I realized this very good build. Mostly for gishes, but any caster would benefit.

I like Sorcerer for the combat synergy (combat panache, assassin's handbook), and Fighter because I'm going to be spending all of my free feats on metamagic.

Sorcerer 1 Feat: Practised Spellcaster(sorcerer); allows no loss in CL for fighter levels
Fighter 4, using ACF armored mage, bonus feats don't matter. Lvl 3 feat, Combat Casting
Sorcerer 2; Might as well not lose the caster level for now; gets to BAB +5
Abjurant Champion 5; utter-cheese! At level five, your CL is equal to your BAB

From there on, it's easy; just use a full BAB class, and the best part is that Practised spellcaster no longer applies to your old CL, so you make up that lost level of Spellcasting.

Please read title in regards to feedback.

[Douglas]

This is a decent gish build for a medium power game, but no more than that. Neither Practiced Spellcaster nor Martial Arcanist apply to spell progression, so you're four levels behind in spells per day and your highest level spells are two levels lower than for a straight Sorcerer.

Also, the Armored Mage alternate class feature is near useless. Just use Mage Armor or Greater Mage Armor instead of actual armor or, if your DM allows the Book of Exalted Deeds, (Greater) Luminous Armor.

[Fax Celestis]

Or, if you're really desperate for actual armor, take a Spellthief dip and use Master Spellthief, or go with Battle Sorceror--either lets you cast in light armor without ASF.

There's really no reason you should need more than light armor, but you can up it to medium with a feat--a feat likely better spent on a metamagic feat or similar.

[Pie Guy]

I knew there was a catch! but my friends don't.

[Biffoniacus_Furiou]

You never need Fighter 4 in any Gish build, ever. Two levels is the most Fighter any Gish build would ever need.

If you want to cast in armor, take Battle Sorcerer and maybe pick up Battle Caster (CA) to ignore ASF in Medium armor, and/or get Spellsword (CW). Then you can go something like Fighter 1/ Battle Sorcerer 4/ Spellsword 1/ Abjurant Champion 5/ Eldritch Knight 9. With Practiced Spellcaster your caster level is higher than your BAB anyway.

Martial Arcanist is worthless, no Gish build would be better off focusing on BAB to use it than focusing on more levels of spellcasting ability and taking Practiced Spellcaster. The only reason to get the 5th level of Abjurant Champion is so you can Quicken your 3rd level Abjuration spells, otherwise it's a dead level. Abjurant Champion 1 gives Extended Abjuration, anything after that is just filler because it gets better HP than Eldritch Knight, it may as well not grant any class features at all outside the HP, BAB, and spellcasting.


Edit:

I knew there was a catch! but my friends don't.

That's called cheating, and it ruins games. A decent Gish build is already a way powerful character without doing that.

[Pie Guy]

Actually, my friends and DM all agreed "Yeah, you could do that.", so it's not so much cheating as using a ruling they already gave.

[Tsotha-lanti]

Actually, my friends and DM all agreed "Yeah, you could do that.", so it's not so much cheating as using a ruling they already gave.

No, it's using the rules wrong because they don't know better. That's cheating. Caster Level has nothing to do with spells per day and spells known.

[Biffoniacus_Furiou]

Actually, my friends and DM all agreed "Yeah, you could do that.", so it's not so much cheating as using a ruling they already gave.

If they mistakenly ruled it like that, and you know that it shouldn't be used that way, then you're still cheating. It would be best to set them right before it gets out of hand and the DM starts outright banning stuff, or making rocks fall because of a cheater's broken character.