So I am wanting to buy some bulk buckshot and have narrowed it down to 4 different loads and 2 different brands. I have ordered two 5 round boxes of each one to test out. I will shoot one box out of each of my two main shotguns I plan on using the ammo in. (benelli M3 and mossberg 590A1)
The ammo is not going to be used for hunting, so extreme long range tight patterns is not important, as well as their performance on deer. It is not the dirt cheap crap, but far from the expensive stuff. I will mainly use it for plinking and range fun, but I want to see if any 1 of the 4 types I ordered perform noticeably better than the others out of my guns. They are all the same price and I could not pick one over the others based on limited online reviews. So that is why I decided to just try a couple boxes of each for myself to see what my guns like.
I will pick up couple packs of some cheap poster board to use as a target. I will use one poster board per load for each gun (that's going to be a lot of targets!). I will probably fire 2-3 shots at each target. I just need to know what would be a reasonable distance to test them at? 20 yards? Is that too far? I do not want to be so close I can not tell the difference between the patterns, but I do not want to be so far away, half the pellets miss the target. Both shotguns have cylinder bore barrels.
So can anyone recommend a good test distance?

I also ordered about 3 different types of slugs as well for the same purpose and test. (both shotguns have ghost ring sights) so I want to test those as well. They are smooth bore (I do not have or plan to get any rifled barrels). So what would be a good distance to test the slugs at as well?

If ya'll want, I can post up the results after I am done. (not sure if it would be of any interest to anyone here)