2 3/4" and 3" should work very well if your gun takes both. Honestly, i'd stick with 2 3/4" at first at least. Nothing wrong with them and they tend to be cheaper, as was listed above, about 15 bucks for 100 shells. Those are birdshot, but a lot of practice and fun can be had with those, and they are more useful than a lot of people realize.
I use those all the time. I know they are not the best, but they work good enough. I shoot quite a bit of shotgun shells and clays so I have to try and keep the cost down.
I shoot Estate 12 ga. 2-3/4 1-1/8 oz. 7-1/2 shot Cartridges when I am trap shooting at 3.59 a box is about the best price you can find...they are made by Federal !
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[I]You know you might be facing your doom,when all you get is a click when you're expecting a BOOM!:( [/I]
I agree. 2 3/4'' birdshot shells work fine. If you should run across the shells without being sure what type of shot it is, the higher number shot is the smaller and finer pellets like the 7 1/2, 8, etc. I believe a 4 is a pretty potent buckshot type load and good for defense but anything like that or 00 buck is gonna hurt if you go shooting it alot. I have a 5 pound Winchester Model 37 and even the birdshot loads in that light shotgun still kick harder than most any of my rifles ever could! I once launched a slug out of that old gun and it looked like I'd just fired off an elephant gun...
Those value packs you can get at Wal-Mart are fine. 100 rounds for around $15 usually. Winchester 2 3/4 inch, 1 1/8 oz., 7 1/2 shot. That's the one's I got. Inside they're broken up into 4 boxes of 25 just like the other stuff on the shelves.
Winchester Universal #8 or 9 for trap, but I recommend a 20 ga. for skeet. some of those targets are too close for 12 ga. unless you're an olympian shooter.
I shot 4 rounds (25 targets a round) of trap yesterday, the loads were federal 2 3/4 inch, 1 1/8 oz, 3 dram. eq., #8. I was using my mossy 500a. After the first two rounds the recoil was getting to me. The pros shooting there said 7/8 from the 12 ga. are better on recoil. Do they make 2 1/2 inch shells for the 12 ga.?