I'm scouring the net looking for loads for my 7MM Remington Magnum and have noticed that some loads only list bullet, powder, and charge. Does the brand of brass and primer matter or are they interchangeable based on the shooters preferences?

Each brand and size of primer can affect a load differently and cna result in higher or lower pressures so you have to work up a load from the beginning anytime you change primers.

It does matter! in that the thickness of the brass is different which gives a different internal capacity these small changes can effect the pressure generated and the velocity of the bullet. the primers do the same thing. reloading is an art of consistancy, so if you mix brass, primers, or other components you will not have good groups and could result in a dangerous load if you don't work up from a starting load when trying a different component.

I'm not planning on mixing them. I'm wanting to try a 162 gr. hornady/H1000 combo, but it doesn't list what brass/primer to use. I'm trying to figure out what ones would work.

For primers, I definately prefer WLRM's. They give the most consistant and hottest flame of them all. As to the problem of brass, keep it all the same, whether you choose Winchester, Federal, Remington, Sako, or whatever. Different manufacturers have different internal capacities. This, in turn creates different pressures upon firing, which will affect accuracy. Seating depth also will affect accuracy and pressure. The mixing of brass is more critical in small capacity cases than the big bores, but the problem still is there. If possible, get all of your brass with the same lot number, and enjoy your reloading.

Been loading for my 7 mm mag for over 20 years and this is what I found out was best for my gun. (each gun is different so you will have to experiment) Federal primers. remington brass, IMR 4350 (max load is 63 gr.), and 150 gr. Sierra gameking BT or Noslar partition 150 gr. I've tried the H1000 but got more consistant groups with the 4350. I've also used 4831 with good results. I find the the Federal primers burn a hotter than the winchester. I also like to shoot the bullets with the boat tail design. they seem to group better.

not nearly as much as gun and shooter.............

I think primers don't make as much difference. Brass weight however I think makes a difference. Winchester brass is thicker and therefore holds less powder/water etc than rem or fed brass. This will raise pressures more so than a primer, unless of course you are going from a normal to a magnum primer.

I guess a better way to word my question would be if a load calls for hornady brass, could you use winchester or remington? Same thing with primers. If it calls for one, could you use another?

You could get into trouble substituting cases, expecially with heavy loads of powder. I do not re-load for the 7mm Remington Magnum and do knowtheweights of the various brands of cases. Before substituting brands of cases, weigh them first. Let's say that you worked up a heavyload for a thinner (lighter) case. That same quantity of powdercan cause pressure to go up dramaticallyif itisused in a thicker (heavier) case.

Isometimes substitute primers in my lighter loads but not in the heavy loads.