Newby with ammo questions.

I am buying a .303 #4 Mk1 from a reputable gunsmith, (he built a sported Masuer 98 for me), he is cutting it down to 24" for me, and putting on a fixed (drilled & taped) Weaver slotted rail.

I plan to hunt wild hogs and whitetail with it, and a butt load of targets.  I usually use my .308 (the M98) or .243 but the urge to get a .303  was overwhelming!

I know Federal, Winchester ans S&B sell the factory stuff (I do not reload), but are there any brands to avoid?  I never use the Russian stuff though.

"Keep the brass, you can sell it or trade it to other shooters. "
Good advice Ed

I don't have a brand to avoid but most loads with heavier bullets have boat-tailed bullets which some Enfields don't like. But most 150 Gr bullets are flat base which they do. Unfortunately its a one-on-one thing with the preference & you have to test your rifle to see if it is OK with boat tails or not. That's why most Enfield shooters run flat bases because every gun likes flat based bullets.

The problem with  boatail stems from cordite which was used to load most 303 British militry ammo. It is very stable under hot conditions but it burns very hot and produces a particular wear pattern on the rifling. Boatails are particularly effected by this.  The Brits tried boatail bullets in their service rifle and dropped them because of poor accuracy in their rifles resticting boatails for machine guns.  Thee are some rifle that did not have much cordite put through them and they digest boatails but there are some rifles that will be moa with flat bases that will key hole boatails. I got one btw.