If you have the Lyman 49th edition or their Pistol & Revolver III you can compare the data I used. Remember to work up from a start charge, or no higher than a mid-charge. The 7.4 gr load is .2 grs above what Lyman lists for the SPEER 147 gr TMJ at 7.2 grs that has a fairly short OACL of 1.115", and as mentioned, my loads are 1.142". If you need it, I wrote an article on finding the correct OACL for your bullet and your 9mm pistol at the Western Powders blog going back a few pages. So here's the thing about the slight increase in powder charge. A longer OACL certainly helps and lowers pressure a bit, but the 147 gr. TMJ load shows a tested pressure of 29,000 CUP while SAAMI Max Average Pressure, MAP, for the 9 x 19mm is 33,000 CUP/35,000 PSI. Two different test methods, so two different pressure values for standard pressure loads. For a load to jump 4000 CUP higher and into +P, it won't be because of a .2 gr increase of Accurate No 7.
I mentioned that I use Silhouette for my 124 gr defense loads in the thread I started about QAS in the general section. It's treated for low flash which is a must for defense loads. It does not, however, have the gas to push 147 gr. JHPs much over 1000 FPS. True Blue is another powder I use for the same reason where low flash is a natural characteristic of the powder. It, however, runs out of gas at around 1050 FPS where faster loads would put pressure into the +P category. Accurate No 7 was originally designed for heavy bullet 9 x 19mm loads and it excels at that. From 1092 - 1118 FPS I can tell you that recoil is more noticeable than the loads you normally shoot, but it is by no means brisk. The only defense cartridge I shoot that's subsonic will have .45 ACP stamped on the case rim. But that's me. The WIN 147 gr JHP is a very good bullet at an excellent price, and expansion should still be pretty decent if you load them at around 1000 FPS.
