Re: How do you carry extra ammo into the field?
If hunting in the midwest within a mile of my truck, I typically have a muzzleloader. So I have what is in the tube plus 3-4 reloads with me, either in a shotgun shell holders on the stock in small tubes (if a smokeless ML) or in commercial reload tubes in my pocket. Usually, also a 41Mag revolver or Glock 23 on my hip, for coyotes/meth head encounters (not unreasonable in the area I hunt, property owner demands I carry a sidearm as he's had scary encounters). Sometimes a second long run (ML or 44 carbine). If I have the 44 carbine, 5 in the gun plus 8 more on the stock holder.
Out west, I'm usually backpack hunting 7-10 miles from the vehicle. I carry 4 rounds in the gun, 6-8 more on the stock, and 10 more in a shell wallet in my pack. It's heavy but I was lazy once and figured 8 on the gun was enough and left the wallet at the truck for weight...shot a mule deer, gave him a second as insurance given terrain. Then found an elk, pumped 5 into him before he showed the effect....when recovery could become next to impossible if they cross the next ridge you keep shooting to they are down. At that point, I had one round left and we had to hike out, in the dark, with backpacks full of meat, through thick grizzly country, with ONE ROUND.
Now, I just carry the extra 10 rounds.
Bottom line, I'm a fan of stock holders. Easily accessible and don't affect the carry of the gun.