My handloads that I load.
When you zero a rifle which ammunition do you choose to do it with? Match? Inexpensive range ammo? Does it matter?
A 5 inch group at 50 yds is a pretty big group. Its not necessarily you since you shot a dime size group with the match ammo. Non match ammo can have greater variance in weight or even concentricity from 1 bullet to another, greater variance in powder weight from 1 cartridge to another, and even vaiances in weight or concentricity of the brass. The exact geometry of the bullet can add a variable as well ( i.e. hollow pt, spitzer, softpoint, spire point, how elongated the spitzer mught be, etc). Further, different weight of bullets, different manufactures, etc, will usually change the point of impact somewhat. In Hunters Safety we instruct the student to both sight in their fireams and practice with the ammo you expect to hunt with ....just because of potential variance in the point of impact. Oh, yeah, you can see some change in the grouping and point of inpact between a cleaned and oiled barrel and a fouled barrel. Thats why I am loath to do a cleaning of the bore of my rifles after I make the final sight in check just before hunting season. Unless I hunt in the rain or something, I try to leave the bore a bit fouled from that last sight in until I'm finished hunting for the season. Its not usually a huge difference between a clean and fouled bore , but often is a couple inches or more at 100 yds (double that at 200 yds).
What kind of firearm is it and what are you trying to do?
I zero for the ballistic characteristics of that round. It's situational.
1:7 twist piston carbine. Manufacturer recommends 77 grain ammunition. They state they use BlackHills 77 grain OTM Mod1 when testing each build. I used this and was accurate. 62 grain Federal, significantly less expensive was less so.
So your recommendation follows the results I was having exactly.
So you end up having to go through the zero process quite a few times a year? I assumed it was a one time thing after buying a new rifle.
Learning curve, for me, is sometimes steep.
If the shot you're taking is important you will want to confirm your zero and make adjustments if necessary.
An easy/cheap bore sighting technique that will get you close is to remove the upper and the bolt and carrier, then look through the barrel at a target as far away as you can. I put my upper on a bag so it won't move then I look through the scope and adjust until they match up. It's a rough gauge but it should get you on paper to limit the amount of rounds it will take to get a good zero.
This statement alone makes me realize I need to read a lot more about this to get it right.
I'm guessing many of you were taught in either the military or at a very young age. Every time I think I know something I have to sit back down.
As generic answer :
Do initial sight in with low to medium cost ammo of the same weight bullet . After sighted with that, then shoot your match/ premimum hunting ammo , to either verify same poi, or make final corrections.