You were right...you're getting tired. You can't shoot well when you're too tired. Even though I'm new to all this, I've found that form is the number one element of accurate shooting. If the form isn't consistent, you got nothin! If you're doing good for 30-40 shots, you're doing well enough to hold it down for hunting it seems. I've read account of Howard Hill shooting around 400 or 500 arrows a day. However, most of them were for form. So maybe after you take about 50 shots and you're noticing things going down. Walk to about one or two yard from the target but, and just do form drills. Close your eyes, and make sure your form is own. If you condition your muscles to remember your form, you can shoot longer. You also need to be careful of damaging your muscles. If you're truly fatiging, don't push too far. A little push is good, it'll condition and strengthen your muscles, but don't do too much. I don't know how many shots I take, I just shoot 'till I start to fatigue, or 'till I run out of time. If you feel like you're practicing too much, then you are. If you feel like you can't handle your bow, then you can't. A lot of accuracy is mental. The act is a physical thing, but it's a mental thing to know when your shot feels right. That can only be accomplished by practicing. Your mind remembers how the shot should feel. That's why good practice is so important. If you practice bad habits, your mind is going to remember a bad way to shoot, which makes it even harder to learn how to shoot correctly. When I play hockey in high school, the coach said it's not the quantity of shots you take, but the quality of shots you take. It applies to archery too. Taking good shots is a lot more important than taking a lot of shots. Shooting a lot won't make you a good shooter, shooting well will make you a good shooter. If that means standing point blank of the target face-giving just enough space for the arrow to safely clear you and the bow-and closing your eyes and making sure your form is on, then go for it. I don't think the amount of shots you're taking is relevant, just that you're taking good shots. If you think, "If I take 400 shots a week, I'll be a good shooter in six months," you're setting yourself up for failure. If you take it one shot at a time and think, "If I can find how to take one good shot, and duplicate that shot, I can shoot well," then you're on the road to success. You have to find out what works for you, but I'd suggest shooting 'till you start to fatigue, then getting really close and closing your eyes. This will allow you to focus totally on your form and not where the arrow will go. 'Cause at this point, it's not about where the arrow's hitting. Shoot a few more arrows like that so you know you're not developing bad habits, like plucking the string on your release, short drawing, not holding your bow arm stead, etc.. In the end, you need to do what works for you. It may be different than my suggestion, and that's fine, as long as you find what works for you. Have fun.

God bless,
Brandan