In reference to one of the comments from the UK. I agree those targets suck. I've messed around with different targets to find what works the best for me. So far, it is cardboard backer and a bright green square "dot". A member here gave me a roll of sticky back lime green paper. It makes for easy seeing.
Another thing I do, is use paper plates. I draw an outline square with a black sharpie, and fill in the middle with a highlighter. That works good for me out to 25 and 50 yards.
When I bought targets, EZ2C brand bright orange worked well.
I've found I can cut my groups in half depending on the targets used.