You do not need to be able to hit a target at 500 yards, but you better be able to hit the targets that are closer to you. When the zero’s defense force comes for you, they will be a lot closer to you than 500 yards.
I practice hitting targets at 5, 20, 50, 100, and 1000 yards.
Also, with my AR I am very accurate to only about 400 yards, because of my eyesight (I do not have a scope on my AR), which is not a good as it was when I qualified as an expert. But with my cheap Mossberg 100 ATR and cheap Simmons scope, I can nail them at 500 yards. However, I do not consider the bolt action 100 ATR to be an effective weapon of defense.
When the SHTF, most of the fighting will be real close and personal. I will use my Remington 870 12 gauge,and my SA XD 45 ACP to protect my family. If the fighting gets to the streets, then I will use my AR.
Train your sons and daughters, take your friends to the range and teach them too. We will need everybody we can get to stop the libs from enslaving us.
When SHTF most problems will be less than 50 yrds with a possibility for longer ranging. You must absolutely be proficient at the distances under 100 and have the tools for that.
I am comfortable with bolt action if needed but prefer a semi .308 or greater with a muzzle break to reduce lift and assist with getting back on target.
Comfortable with revolvers with speed loaders for 25 and under. I just like the reliability and I breathe and Aim. I don't send a lot of rounds out as I am focused on going through the target. Always shoot at the chest and continue until they stop. A good semi like a Kimber will provide excellent tool here.
All around for 50 and under with very little practice is the 12 gauge with double 00 buck. Make sure the barrel is 18.5 inches, to stay legal and provide accuracy. Couple of hints, 00 provides at least 8 pellets in one shot. Prefer 2 3/4 most economical and the least kick of the other sizes. Will accomplish the same task. For crowd control you can shoot the concrete at 15 degrees and take them out the legs or shoot the closest one by focusing on the front bead, in the chest. don't worry about the back sight if you are inexperienced and haven't taken the time to learn to shoot properly. With 8 shot coming out at 15yrds you will hit the target and anyone to the left or right.
You probably already know that sights are available for both the Bolt guns and the AR type.
These aperture style sights take most of the guess work out of lining up a long range shot. They are pricy when you consider the additional cost of the rear aperture and the fore sight assembly. However, just about anyone can be taught to hit a six inch circle on a regular basis from 600 yards.
AR-15 Flat Top
1 piece mount
Rear sight
Standard Right Hand
Rear sight
The sights on my 30 Cal Target rifle are simular to these. I don't have a bit of trouble hitting the X Ring.