There has to be a reason why your loads were not up to scratch mate, and you can bet it will be only one little thing.
Sit down and go through the entire process (without actually loading anything) and check to see if you are not doing something or not doing something quite right. Write down your process from go to whoa.
Once you have done that, load one round carefully, paying particular attention to each step. Sizing, priming etc. When you measure your powder load, confirm the charge from your data, then carefully weigh the charge on your scales to check the weight to ensure it is spot on. Ensure your scales are correctly balanced and set before using them. Check the weight of your bullet...check the seating depth (I initially seat the bullet to the factory OAL specs, then in later loadings may play with the seating depth to fine tune the load). I like to crimp my loads...not necessary in every case, but I prefer to do it for uniformity.
Once you have loaded that first round mark it with a Sharpie marker as #1...then load another 5 or 10 the same way. I would then take these rounds to the range and fire a couple of groups with them...a 3 round group at 50 yds, then another at 100 yds. Allow your barrel to cool down significantly between shots. This will ensure that you are firing each shot from a cool barrel each time.
I would keep say 3 rounds for the end and you could approach another shooter (that is a reasonably good shot) and ask if they could fire a 3 round group from your rifle with your loads. Explain this is to eliminate the TLO factor from the equation. This will ensure that the most important nut o the rifle isn't loose...the nut behind the butt.
If your shots are still all over the place, then its time to look at other factors. Have your rifle checked by a gunsmith for any problems that might cause inconsistency etc.
Apart from that mate, the only other thing I could suggest is to try some factory loads. It might also be worthwhile to get someone you know to be an experienced hand loader to watch over your shoulder as you load a few rounds. If you are doing something wrong, then he should be able to pick it up and correct it for you.
Let us know how it goes mate.
Cheers, Vince