Sorry it took so long to get back, i've been busy playing! lol!!
Ok, so you can bind the two buttons! On XIMmanagement when you go to the second page that shows the buttons and what your using. There is primary/secondary drop down on the left. Leave it alone.... there is another primary/secondary on that same page in the middle kind of un-noticeable unless your really looking for it.... when you swich to secondary there should be NO buttons used on any of the secondary..... then you should switch that toggle to the same button as aim. When done and you save EVERYTHING! plug back into xbox when you are playing and aim down your sniper rifle your breath WILL be held.. It works just as good as I thought and wanted.
The only CON: sometimes when your looking for people too long you will lose your breath and aiming will go everywhere, so if your not quick-scoping and/or if you like to play hardcore and want to "camp/quickSCOPE" then I would add/copy it as a config....
If you can't figure it out hit me up, I'd be more than happy to share with..
thnx for everybody's advice
