The story of my life… 
I use a small ladle, and, after ladling batter onto the griddle, I use the bottom of the ladle to spread the pancake, using a spiral motion from the center of the batter outward. I remember watching my mother do this, and it is a natural to me when making pancakes as breathing.
Use a round pan, then pour enough batter so that the entire bottom is covered. BAM round pancakes. Round HUGE pancakes.
The batter needs to be much like whipped cream in thickness, use a ladle or measuring cup for consistency in the amount of the pour, and pour from a low height, just above the surface of the HOT griddle.
Cub Mistress, the acknowledged Pancake Goddess of my family & friends
Or you could do like Larry Fine. Moe took one look at Larry’s oddball flapjacks and asked, “What is this–Phi Sigma Delta?” 
When I was a scoutmaster, we had our new scouts make pancakes using the lids of a Dutch oven. They’d get the batter the right consistency, and we had them use a cup to measure the dough and then pour it onto the hot, buttered Dutch oven lid that was inverted over a wood fire.
I had one scout get ready for his first try. The batter was perfect and he had amount right. He held the cup just above the lid, but got nervous just before pouring. I said “go for it” and he suddenly lifted the cup of batter a good 12 inches above the lid and poured it out all at once.
If you know about Dutch ovens, you know that inverted lids are slightly concave. If he had just simply poured from an inch above, he’d be fine. From 12 inches, the batter went flying about two feet in every direction.
His next pancake was much better. The key is practice, right consistency, and be brave!
I was a busboy at a IHOP for a year while I was in high school. They used a dispenser. Sort of like a funnel with a handle across the top with a trigger to squeeze to let the batter out. If that’s not working for you, it’s your batter.
The secret to why your kid is so mellow when you drop him off at the sitter. 
No no, you have it all backwards. They didn’t use a head gasket to make the hotcakes, they used the leftover hotcakes to make the head gasket.
What the OP needs for perfectly round pancakes is a pots cover.
I was really hoping this was a picture of the Staff of Ra headpiece with the crystal removed.
Lisa’s pancakes were a running gag in the show, as I recall. I know I saw her using a head gasket to make them, though I was unable to find an image (I didn’t look for videos) when I posted.
Just to be different, I want square pancakes!
Would you settle for silicone shapers for owl, skull, rabbit, sunrise, and ring shapes for pancakes and eggs?
(post shortened)
Is your stove top level? Use a level to be sure. Is the base of your pan flat? Some pans warp over time or the edges droop leaving a high spot in the center. Does the batter have a uniform consistency? A combination of thick and thin batter will not flow evenly on the pans surface. The batter should have a consistent viscosity.
Batter poured slowly on to a hot buttered (greased) horizontal pan should spread out evenly and form an almost perfect circle unless something prevents it from doing so. Check your tools (stove and pans), and beat your batter into a more consistent fluidity.
Hope this helps.
I can’t believe anyone cares that much about the perfect circularity of their pancakes. I can see it if you need to do something else with them that calls for the shape to be perfect, but if you’re just going to eat them off a plate…why do you care?
A round pancake is a function of a) smooth batter and b) a good pour. Both those things mean that the pancake cooked through evenly.
So a round pancake is probably going to be tastier than a misshapen one. Not because of the shape, per se, but because the shape (like the taste) is the result of other important factors.
Symmetry! Symmetry and congruity, and the laws of physics!
I thought she poured batter all over the griddle and then cut out the round pancakes, leaving the head gasket behind. And presumably it was quite sturdy due to the extreme sturdiness of her pancake batter.
I loved that show. I loved that Lisa was such a damned good sport.
Reminds me of Laverne…
“Lucky lucky lucky! For the next ten minutes, everything comes with pancakes!”
“Betty please…”
Restaurants I’ve worked at only ever used ladles (2 oz. IIRC). The temperature of the batter and griddle would make a difference, but assuming they were optimized it was a pretty easy (though easier if you’ve done it 1000s of times). Biggest mistakes I observed were new cooks trying to do too much (pressing down and swirling, usually) with it. If you just sort of dropped it and made a circular motion on a hot griddle it would be circular on a flat top. Same thing goes at home though I usually use a pan.