I have never been a fan of 147gr round noses for a few reasons. 147RN's have the longest length on the market and there are a lot of problems with that. As the bullet gets larger (and OAL stays the same) the internal volume inside the case decreases and shows a higher degree of variation. With that, I doubt your loads are a perfect 127 everytime. Probably more like 122-132 with an average of 127. That variation could be a source of inconsistency.
Furthermore, when you load bullets deeper in to the case, you have a greater chance of deforming them. Do this: measure the diameter of the base of the bullet you are loading using a micrometer. Using your press, insert the bullet into a freshly sized case. Now, pull the bullet and re-measure the base of the bullet. I'll bet it will be a few .0001's smaller. This deformation is a major reason why bullets loose accuracy and people observe greater accuracy with HP's and Hornady tapers the base on their XTP.
Also, Titegroup is a good powder, not a great powder for long distance accuracy. Titegroup is a very fast buring powder with average accuracy and delivers its advantage through reduced felt recoil allowing for faster follow up shots. Its not the powder to use for trying to generate 1" groups from 25m. It is ideally suited for practical shooter looking to make 90% of their shots from 18m away or less and take shots in quick succession.
If I were you and was concerned with accuracy I'd load those bullets as long as I could and switch to a powder like CFE Pistol, N330, or N340. You will notice increased recoil for the equivalent PF over using Titegroup but the trade-off will be tighter groups at distance.