Pacific also lists the 284 Baer reamer. I'm pretty sure it is based on 300 H&H length belted magnum brass. Probably similar to the 7mm STW. Hope this helps.
It is a necked down version of the 308 baer which is a 340wby mag parent case. He does the popular calibers. With the advent of the high bc vld bullets it is a very popular long range elk ctg