2 different breeds I own are still smallish

[Geminidragon77]

OK, if this post is in the wrong topic, please forgive me.
I have 2 breeds of chicken I am raising for eggs. Golden Comet & Barred Rock. The Comets were bought March 2022, the Rocks in July 2022.
They are fed well with powdered vitamins added at least 3 times a week. I have fed them a lot of mealworms, both dried and live over the last year. Greens and corn and other snacks. A Purina feed at 17%, a local hen house blend with Sunflower seeds, corn, dried peas, chicken feed and other stuff.
My question, which I have asked other local chicken people is, why are they still smallish or how long does it take for them to reach "full" size? There are only hens, really secure pens, unfortunately we can't let them free range in the yard so they don't have access to grass to scratch in. And their pens are under 2 huge oak trees, so I line their inside pen with hay, and the outside with wood chips shredded from trees taken down on our property.
The picture is a friend's Barred Rock, mine after a year and 3 months are about 1/2 this size.
Any suggestions or clues, or information would be greatly appreciated.

 

[Tookie]

Could you get pictures of your chickens?
Are all of them the same smaller size?
Where did you get them?

 

[Amer]

Hatchery Plymouth Rocks will never be the same size as the Plymouth Rock is supposed to be since they are selected for egg production, not size. While your friend’s bird is also a hatchery bird she is bigger probably due to the fact that hatchery bird genetics are pretty variable. Another thing to note is that to reach their full genetic potential, large breeds need high protein feed for the first 6-8 months of their life. Chickens stop growing in height after their first year, though they often continue to increase muscle mass through the next.

 

[Geminidragon77]

Could you get pictures of your chickens?
Are all of them the same smaller size?
Where did you get them?

The Comets came from Tractor Supply in March of 2022. The Barred Rock hens were ordered from McMurray online and arrived July 3rd 2022.

Thank you Amer for your response.

Another concern on the Barred Rocks is the size of the eggs they lay. Comparatively they might be considered small even to a regular eggs you buy at the store?
Are they eventually going to lay bigger eggs?

 

[Amer]

The Comets came from Tractor Supply in March of 2022. The Barred Rock hens were ordered from McMurray online and arrived July 3rd 2022.

Thank you Amer for your response.

Another concern on the Barred Rocks is the size of the eggs they lay. Comparatively they might be considered small even to a regular eggs you buy at the store?
Are they eventually going to lay bigger eggs?

Small birds lay small eggs and storebought eggs are relatively large compared what is laid by most breeds which is why they are called “large.”

 

[Tookie]

The Comets came from Tractor Supply in March of 2022. The Barred Rock hens were ordered from McMurray online and arrived July 3rd 2022.

Thank you Amer for your response.

Another concern on the Barred Rocks is the size of the eggs they lay. Comparatively they might be considered small even to a regular eggs you buy at the store?
Are they eventually going to lay bigger eggs?

I agree with everything @Amer has said.