If a fellow wanted to have some factory loads, here is another option for the older 12ga double:
"Federal Vintage Gold Medal Ammunition 12 Gauge 2-3/4" 7/8 oz #7-1/2 Shot Box of 25 (Not for Use in Semi-Autos)
This vintage ammunition was produced specifically for MidwayUSA to the following specifications:
7/8 oz shot, 1200 feet per second velocity,
5,000 pounds of chamber pressureThese specifications were designed to be kind and gentle to all older break-open shotguns that are safe to shoot with modern ammunition. This ammunition is also ideal for trap and skeet practice, or for use as a light game load - wherever a 20 gauge load would be acceptable."
http://www.midwayusa.com/eproductpage.exe/showproduct?saleitemid=417403&t=11082005I have shot a lot of this and it has delivered very good performance.
Doug