A box or two of specials in your mag won't gum it up enough to keep you from loading it. Shooting a box of this and a box of that really won't teach you enough to be a proficient handgun hunter, you need to shoot gobs of bullets. You really need to reload to be able to shoot enough to be good. A handgun is more like archery in that respect, it's all about practice practice practice.
About sighting in, ok start out by getting a zero from the bench, but to be truely sighted in you need to know you are zeroed in the position you will most likely be using in the field. When I was in Law Enforcement, it finally dawned on me that my DA revolver shot way differently depending on the way it was held. A bench zero was quite a ways from an offhand zero. How do you go about finding an offhand zero when you are shooting maybe 4" or 6" groups at 25, depending on how fast you are shooting ect. You shoot lots of bullets, at paper now,(boreing) you eyeball how the group center lies in relation to the bullseye, and then you tweek the sights. Than you do it again and again. Eventually you have confidence in your zero. But then what happens when you use a tree for a rest. Or my favorite field position, propping my back against something in a sitting position with elbows on knees. Does the gun shoot the same place, if it doesn't a good handgun hunter should know. See what I mean about gobs of bullets?
Luckily, for me anyhow, a SA revolver is far less sensitive to the way it is held than my DA. I can even rest the barrel against a solid object and the old SA just keeps putting them in the same group. Thats why even though I keep the DA for defense, when I am serious about hitting little targets I will use the SA.