Hello all. I am new to the site and have found a lot of good info but nothing on this particular question. I am fairly new to handgun reloading and I am loading for my Sig 226 40 S&W and am already finding great advantages to reloading other than the obvious of money saving and availability, but at the range also. I have been reading numerous books and manuals on the subject, one of them being "Reloading for Handgunners" by Patrick Sweeney. In the section talking specifically about 40sw he describes a process of taking a dummy round of almost 10mm length and with the recoil spring removed from the pistol, cycling the round through and the resultant OAL of the ejected round is "the length for your gun" He also describes how to find the max OAL of your pistols chamber by first measuring the OAL of the separate bullet, dropping it into the the removed barrel, measure from the hood of the barrel to the base of the bullet. Add the length of that distance to the OAL of the bullet and that is the maximum "loaded" OAL of that particular pistol. So I did all that. With a resized case of .843, and new bullet @.532 the measured depth was .721+bullet@.532= 1.253. I cycled a dummy round from the magazine, into the chamber and ejected it with a round of 1.207. So I am not sure what this actually tells me? Am I to assume that the longer OAL of the reloaded round will be more accurate given that if I were to back off the length a few thousands from the new length that the bullet has less distance to travel than a spec. OAL of 1.125 before it hits the rifling? The other effects being that there is more dead space in the shell, less brass to bullet contact, is he saying that I can load a heavier wt. bullet and keep the same grain weight of powder? He ends the section saying that when crafting ammunition for your "competition" pistol the "correct" OAL of .40 ammo is what it is, there is no common or average length.Is this a common or even a safe process? Thanks for any info or response's.