This has been covered in depth many times before. Estates, Federal Top Guns, or WalMart Federals. They are the same hull with a paper base wad and steel head.
18.2 grains of Red Dot or Promo, Federal 12S0 wad or Claybuster clone, Federal 209A primer or Rio 600, 1oz of decent shot gives about 1200 fps over my chronograph. 18.7 grains of Red Dot or Promo, Federal 12S3 wad, Claybuster or Downrange clone, Federal 209A or Rio primer, 1 1/8 oz of decent shot gives around 1200 fps over my Chrono. These loads have been tested at fairly cold temps and have given good results. The Downrange clone of the 12S3 works pretty well. All pattern testing was decent for all of these loads. The Federal wads seemed to be marginally better, but the 12S3 and the Downrange DRF8 seemed about equal. Testing was done at different times, so the results were within a reasonable margin of error, considering only ten samples were fired of each load. I don't have pressure data for these loads, but data for higher velocity loads using the same components and powders were well within limits, so I'd expect these to be under 9500 psi.
I load the Federal Primer on the first loading and then the Rio for the second, since it is oversized. It will help seal the case better, since the paper base wad seems to allow a little gas leakage after the first loading on many of them. I toss them after the first or second loading.
I have had issues with some wads designed for tapered hulls like the Remington or Winchester. I settled on the Federal type wads since they worked rather well. They are designed for a straight wall hull. If you want to avoid a lot of experimentation and possibly poor results, the loads I listed above will work well. I have also used Clays powder and several others with decent success. I settled on Red Dot and Promo, since I have/use a lot of it.
Be certain that the hulls were never wet. You should look inside each one and look at the paper base wad to see if it shows signs of swelling due to moisture, or any other irregularities that could be a problem. The tubes also have a habit of coming loose from the base, on occasion. I have had a couple tubes pull free of the head as they were ejected. Usually not a problem, unless you try to stuff another shell in the chamber. Just give them a quick tug to see if they are loose before loading.