Content Image Width Not Matching Text and Featured

I’ve been having a problem with the images in my entry content not matching the width of my text and featured image. My featured image and text span the full width of my posts, but for some reason my images are being shrunk down. I’ve messed with the CSS, the PHP, the media settings, post settings, etc. I’ve even made sure the image dimensions meet the same width as the container, but nope. Still not working, they’re still being shrunk down. I’m stumped. Does anyone know how to fix this issue? It’s driving me nuts. Any help is appreciated, thanks!

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