Hard to tell without a video or picture progression.
Catch the bar with your finger tips. ELBOWS UP, or out a little.
I've been having this problem since I started lifting, my coach says it will just take time. I've been doing a lot of wrist stretching, tricep stretching, and shoulder stretching. My coach said that some standards the Russians had for kids to get into Olympic Lifting was the ability to touch your hands together behind your back when doing a tricep/shoulder stretch (the one where you take one arm and bring it behind your head so that your fingers are pointing towards your feet, and the other hand you put behind you and reach up towards the hand behind your head). Been working it this for the past few weeks, and things are improving but get a lot of pain in wrists and shoulder.
Bulgarians I have heard measured thumb lengths also as a test for suitability in 'hooking' the bar
A technique I've been trying for the past few days now that seems to be working amazingly quickly is pretty much foam rolling on the wrists, triceps and shoulders. I ordered this device called "The Stick" (google it) and a "Trigger Wheel" and I've been using them on my wrists.
My technique is to start by rolling the trigger wheel on the wrists, then do a wrist stretch, then roll them again especially on the places I felt pain on during the stretch, then stretch the wrist again, continue this progression. Works well if you have an office job and can just sit around rolling your wrists and then stretching. I have my brother get my triceps and shoulders with the actual stick at home, really loosens things up.
One other thing, I was told, and people in this thread have said "try a wider grip". Well I've been using a wider grip but things really weren't progressing. So on Tuesday I tried a grip of about a thumb length from the knurling and I was able to rack it a lot easier, getting all 4 fingers under the bar (albeit not far enough). I would argue that it might be a good idea to load up a bar for a front squat and then just try out a bunch of different widths to see what's the most comfortable.