If it were me doing a build (oh wait, I am!) here is the list of "first thing" to do's:
1. Bolt Buffer (just about any brand, I prefer weaponcraft)
2. Targer Hammer (Rimfire technologies #1, VQ #2)
3. Polish engagement surfaces on factory sear and disconnector
(You know have a sub #2.5lb, crisp trigger).
4. Remove trigger return plunger and tap hole for overtravel screw, notch top of factory trigger and install $0.32 torsion spring from Ace Hardware.
MUCH SMOOTHER TRIGGER!
5. You can now drill/tap a set screw in the factory disconnector to take up any pre-travel if you like...
#6. Barrel
...just stay away from Butler Creek.
GM (Green Mountail) makes very accurate barrels at a very low cost. Beyond that, you're paying for a name, custom length, or "fancy" flutes.
There are a few guys that will set-back and rechamber a factory barrel with a bentz chamber for a reasonable cost--and they will shoot as good or better than most aftermarket barrels! A great alternative if you want a "stock" look.
#7. Stock
I won't even touch on this as they are so darn many on the market in so many variations. Just know some thumbhole stocks on the market are VERY uncomfortable to shoot off-hand, and are best left on the bench.
From here, there are about 50 billion other things you could do...
Rather than buying an aftermarket bolt, send you factory unit to Randy at CPC and have him re-work it. He wil pin the firing pin, jewel the bolt, square and headspace, and reshape the rear of the bolt for ~$60 and you will be just as good (or better) than an aftermarket piece.
I'm a realy 22lr junky, and have built a few 10/22s in the past few years.
I'm building my last two currently, as I will NOT buy any of the new Ruger 10/22's since the bolts are now MIM'd, the trigger groups are all molded plastic, the receivers are "krinkle painted" which chips and flakes too easily, and the hammer has been re-designed (and stinks!).
My local Big 5 happened to have two old-model, all aluminum 10/22's on the rack and I scarfed them up as soon as they went on sale.
