I have tried it right on the lands. You have to reduce your loads alot and I lost alot ofvelocity and accuracy was just ok.You want some freebore. Imagine trying to bust thru a door if your right up against it, and the pressure it would take compared to a 3ft jump.

With barnes, TBBC, scirrocos and failsafes, I like up to .1" jump but too farin the case, you also get high pressure signs too. Its a balance. For most other bullets without solid shank and guilding metal, I like .005".

Another problem with loading too close is variances in each OAL. With a real nice redding competition seater, you might be able to get each bullet seated and none vary more than .0005", and thats if each piece of brass is really nice and neck maybe turned. With regular old brass and a regular RCBS/redding seater, you will see variances with with a stoney point comparitor up to .002". So thats another reason to seat .005" or more away.