The 30 BR is a fun low recoiling chambering created for shoot for score bench contests. It may work for limited hunting but it is cost prohibitive and impractical.
I have one and here are a few insights:
You will have to neck up either 6 BR or 7 BR brass as no 30 BR exists. A custom reamer will most likely have to be purchased. Most existing reamers have short throats for 118-125 target bullets and the neck diameter requires neck turning.
link for details: 30BR Guide - 30 BR Benchrest Lapua Cartridge with Reloading, .308 Bullet, Accuracy, and Competition Info
6 BR norma brass has a very tiny flash hole, the RCBS decapping pin will get stuck in the hole. It was a surprise to me when it happened...7 BR rem brass has a larger flashhole. All BR brass uses a small primer.
If you are going to use a repeater the magazine/feed ramp will require attention. This round will not consistently feed from my short action rem 700. I single feed and only use my rifle for paper punching and practice with a bi-pod and sandbag.
To my knowledge there is no ammunition available.
The one advantage to this round is low recoil and low heat. I can fire off a string of 10 shots in 90 degree weather and the barrel only gets warm.
I think you would be poorly served in choosing this round for deer hunting. The 308 would be a far better choice. If you want less recoil or velocity you can always download the 308 .