Ok you have misunderstood what I asked. I did not ask the shell length. I asked what dram equivalent the load was. Sounds like you are new to shotgunning? Let me try to help out. A shotshells load and velocity is measured by the weight of the charge of shot and the amount of black powder it took to equal todays smokeless powder. As black powder was measured in drams loads listed how many drams of powder they contained at one time. When the switch was made to modern smokeless powders shooters had no idea the velocity of the load as powder was now measured in grains and with so many types of powder there was lots of variance in grains to achieve loads of equal dram velocity with a given shot charge. Modern shells are usually marked on top of the box the dram equivalent so shooters know what velocity the shell is supposed to be. That is why I posted the the two standard or most popular target loads. You cannot use field loads of any length on a clays course, only target loads and in a 12 ga that is a 2 3/4” length hull with shot charges, shot size and velocities that meet approved weights, velocity and will fall within specified overshoot distances You need to determine the load you are using. Many of todays shell boxes are no longer printed with dram equivalent but with the velocity. That is why I gave you a couple loads listed so if you buy ammo you know what to look for. In your gun I would probably use 3 dram 1 1/8 oz(1200 fps) loads to ensure cycling. Often times 2 3/4 dram 1 1/8 oz (1145fps) loads are a bit light on power to work the actions on guns designed to shoot multiple length shells. The gas pistons self meter what they need to work the action but many cheap slower velocity loads lack enough power to cycle the gas valve fully.
Maybe this will help explain better.....stop the frame at the end of the video and look at the info printed on the shellbox lid.
https://youtu.be/Od_bMd3inNs
