Hi to everyone. I am new to this forum and I would like to ask you all about ammo to break-in this gun. I have had only pumps in the past, not anything like the SPX. I really like the looks of this gun and wanted an auto for a HD and to shoot at the range. What I am looking for is info on the cheapest to use to do this, as well as not to kill my shoulder. Is there a specific velocity I need to stay above? I plan on shooting 150 rounds or so for the break in. I have read most of the info on cleaning and checking the correct fit of all the parts, as well as possible deburring the mag tube. I now live in San Diego and I am looking for a place to buy ammo. I went to Walmart but they no longer sell ammo here. I believe I can order it online but I will have to research doing so. Thank you in advance for any info you can share. CB