So I have a 870 super mag, question on the choke. I've missed a few dove that I know I had a good lead in and should have gone down. I mean I've seen feathers come off a few dove. So not sure if it's the loaded I'm shooting or if I need to change the choke.

You need to pattern the gun. Find out which shell patterns best.

What choke are you using? For dove I would use Imp. Cyl., and definitely nothing tighter than Modified. If you are using Imp. Cyl., already then pattern the gun. Could be loads. For dove I recommend 1 1/8 ounces of 7 1/2 or even 6's if most of your shooting is greater than 35 yards. Also use standard velocity shot-shells and not super speed as they don't pattern well. My but has worked for me for 45 years, and thousands of dove.

Agreed ^ ^ ^ ^ ^ ^ ^ ^

#7 1/2 shot is usually the best medicine.

Is this a recent development that suddenly started happening?

Are you using "bargain" shotshells?

Do you wear corrective lenses and has your prescription changed recently?

Usually, feathers flying means a shot to the butt area. Just a little behind in lead.

This 100%

x2

While there are things you can do... using the correct choke, using correct shot, patterning your shotgun... limiting your shots to ones within range, etc. A shot gun shooting shot shells is never and will never be like shooting a rifle.

So much changes, birds fly double the speed with the wind as they do against some are slower some faster morning doves duck and dive like a dang dragon fly. I never got too worked up missing a dove, and 99.9999999% of mechanical failure is still caused by operator error.

This^^^

You also need to practice. If you are seeing a few feathers generally you are not following through and you stopped the gun at the shot.

x3

Ditto....I only. Hunt with 870's...great guns....just patern the loads and maybe hammer a few clays as practice.