The number one concern with OAL is - will it chamber. This has to be watched in a revolver, if the OAL is too great then it will stick out the chamber mouth and hang the cylinder. Number two - OAL will effect the pressure generated by the powder charge you have. increase the OAL and you decrease pressure with the same powder charge. Case capacity effects chamber pressure. If you have known loading data, that calls for a OAL length of 1.665" with a certain bullet and you increase it to 1.700" then pressure will decrease - slightly. It does not give you a free ticket to dump in 2 more grains of powder. It is an unknown; You must work up slowly and deliberately. I generally do not increase the powder charge if I increase the OAL because I want to work with a lower pressure level. I will only increase the powder charge if I have accuracy trouble or I want to squeeze as much velocity out as I can. the second scenario is not generally me, I go to a bigger cartridge if I want more velocity. The little difference you get is not much to worry about. I am not talking about decreasing pressure by half or any thing like that. BTW in revolver cartridges, I do not increase OAL unless I have to. To me you increase OAL to get closer to the lands to increase accuracy. In revolver cartridges, it is a moot point, because you are not going to reach the lands, no matter what you do. If you would load excursively for the Handi rifle, you might see slight difference in accuracy, but unless you are close to the rifling to start with, I doubt if you will see much difference in accuracy by increasing OAL slightly.