So, been playin' for three years and never really ventured into medium gauge strings, but I play a lot of fingerstyle like Don Ross, Andy Mckee, Antoine Dufour, yadda yadda yadda.

I got some D'Addario mediums (13-17-26-36-46-56) and am totally freaked to go to standard, and still haven't. I have it parked in a Full step down, DADGAD (all flats cuz that G is lookin' like a scary mother) and B C# F# F F# C# (so not parked at all, just all over the place really)

Anywho, The guitar they're on is a Yamaha F335 which has about a 24.5" or 25" scale length (no place anywhere on the internet that will tell me).

Am I supposed to be able to tune this to standard, or what's the deal? I haven't broken anything yet, but I can tell when they're about to, and when I try to go anywhere near standard I know they're about to.

Need some help. Thanks guys.
I've been using mediums for a while and my guitar doesn't like them much either. The trick is to kind of force your guitar to go to standard (I'd stop at Eb first though). Best bet is pegs popping out (happens every time I change strings) or your strings break. The former is easily dealt with and the latter is your guitar's way of telling you to "be fruitful and multiply". Just treat it like a lady and it should work out.
13s in standard on a 24.5 or 25 scale will warp your neck after a while. It's too much overall tension unless you have a double truss.
Prs se Holcomb is the answer
Couldn't I just adjust the truss rod to counter any potential warping? I don't know how to, so I won't, but wont an adjustment avoid the warping?
Quote by Zoot Allures
Loads of jazz guitars are 24.5 and use massive strings :S

jazz guitars that handle that are built differently. you will bow a gibson with 13s in standard tuning.
Prs se Holcomb is the answer