I can confirm that as you have 2 weapons equipped (Ballistic Knife, Crossbow) in Sticks and Stones, you cannot earn kills toward your Combat Knife in that game mode. Conversely, any kills you earn using a the Knife Melee Attack will count towards your 300 kills required with the Ballistic Knife to earn the Kryptek: Typhoon camo.
Assault Rifle Gold Tips:
General, I'd set up classes with no lethal grenades, take extra tacticals if you want, but the lethal grenades don't help your in any of these. Also would run all non-lethal scorestreaks. UAV/CUAV/VSAT. If you're a lower k/d, you can switch VSAT with CP and try and get UAV/CUAV's out of those, but usually those lethal scorestreaks do nothing but slow you down on your road to gold.
Longshots: Hardcore Kill Confirmed. Or TDM, but hardcore. And Target Finder. Makes this very easy. Get a map like carrier, take out your target finder, line up and pull the trigger. With hardcore on, they will drop with one or two bullets out of most assault rifles. Carrier and Slums were where I like to get these. On slums just line up on the wall, across the map the people who headglitch over the barrel will give you your longshots. Carrier is across the map in several directions. I'd back out if you get hijacked and are trying for longshots.
Double Kills: Usually pretty easy, I've always ended up getting these while doing my no perks/no attachments.
Headshots: Certain AR's are easier than others, specifically the M8A1 was the most difficult because you essentially have to get the entire burst on the head. For this gun I played Hardcore mode, still took forever. Other guns, Target Finder will help if you're really struggling.
BloodThirsty: Really just have to focus usually just played conservative once I noticed I got 3 in a row during my no perks no attachments.
No Perks/No Attachments: Do them together. Your K/D will take a hit, but still, load up on tactical grenades and grind it out.
Lol. Target finder makes long shots, and finding enemies at range much easier to me than reflex or EO tech for AR's. Literally would get all my long shots in a single game of hardcore using this setup, and I'm really not that good, but I'm glad I almost got your approval.
He didn't say take your Target Finder and lay prone at the back of the map. He suggested it because it makes a noticible difference to how easy it is to complete certain challenges (Longshots), or earn headshots.
I got one tip. For single shot and burst weapons, use select fire. The extra recoil with full auto will net you some more headshots. I don't know about anyone else, but I have had a REAL hard time getting headshots for the very accurate weapons like burst or single shot weapons.
Very rarely when I get a headshot do I actually mean to do it. For the most part, it is all luck. At least for me.
When I get a longshot. I just camp there. Then keep going back, it only takes 10. Every map has a spot you can camp. Pretty easy. Now bloodthirstys with the ballistics, uggggghhhhh