Sometimes you can tell by appearance and other times you need to try different helmets on. A round shape is wider side-side than a oval shape, which is longer front-back.
Which Charles Owen helmet did you purchase? Usually Charles Owen are built move oval than round and the round shape needs to be specially ordered or selected when purchasing. I’m not as familiar with the Samshield fit, but I’ve heard they run more round.
In which way did the Charles Owen not fit? was it tight side-side or front-back? Or too big either way?
Charles Owen (CO) Does however fit differently from many helmets in terms of the padding inside. They normally have much more padding than other competing brands, thus the initial fit is often fairly tight and sometimes it can even be uncomfortable at first. You want those helmets to be snug though because the padding within a CO does pack down more than say a tipperary or One-k would over time. To measure for a CO, you’d need to measure the circumference around the largest part of your head, where the helmet would sit. For reference, I measure 54cm, which is a 6 5/8. When I tried it on, it did feel uncomfortably tight, so I went up to a 6 3/4 which was still quite tight. I’ve had the helmet for a while now, but it packed down so much that it now rocks and I had to out an anti-rocker in it. That being said, it is still one of the best fitting helmets I’ve had.
