So I am new to reloading and only have my amature Bro to teach me most of the stuff dealing with reloading. What I am curious about is wether or not I have to sight in my gun everytime I change bullit weight or is that basically a myth? I am loading some test rounds in 145gr speer for my big 7 but it is not my choice of round that I intend to run in my gun plus I run a heavier bullet for elk hunting then I do for deer hunting. Should I sight in my gun everytime I change bullet weights or should I just look into getting another rifle?

Do you sight your gun every time you change distance?
When you're not shooting the .375 H&H, you'll call yourself very lucky when you change bulletweight and get the same POI. As to my knowledge, only the .375 H&H is known for its relative stable POI (but I guess the targets for this calibers allow a mistake of a few inches)

In my opinion the best you do is looking for the smallest groupe for each bullet and then you don't change optics but keep into account the different shootingdiagrams when you change bullets, just the same as when you go for another distance.
When you have 2 (or more) aiming devices (f.e. optics you can change without need for adjustment), you can also couple the aiming device to a certain bullet. It would make life a little easier, but still you have to keep in mind the different hold over/under with different distances and left/right according windconditions.

Advice: when you change a lot, keep notes!
Or you soon will loose confidence in your rifle, round or yourself.

Yes, definitely zero the rifle with whatever load you are using. My .270 shoots my 150 grain Speer Grand Slam bear and moose loads about 5 MOA to the left of my 130 grain SST deer and sheep loads. It is impossible to predict the change in POI when changing loads, best just to check and if needed, re-zero.

Yep, rezero if you change ammo. In my .280 I tried 139 grain and 160 grain bullets and there was about 3" difference in the point of impact at 100 yards.

I have a range card for the .270 that has the different bullets & bullet weights I use on it.
The rifle's zeroed for Sierra 130gr flat base & all the others are marked as +/- so many MOA from that setting.
Only checked it out at 100 & 200yds as yet, so further "work" will have to be done out to 400 with boat-tail bullets.

What these fellows said ... ???

If your going to use different bullet weights in the same gun it pays to have a good scope with positive click adjustments with a micrometer style reading. Once you get everything figured out you can record the settings and easily return to them for each weight. You could even have multiple settings for different yardages.

my 270 puts 170grn loads dead on at 100yrds and 130s 3"high I can put plurry near ANY load through it and will put them within 4" of aim point at 100yrds eg all inside a playing card.

chambered221 wrote:

If your going to use different bullet weights in the same gun it pays to have a good scope with positive click adjustments with a micrometer style reading. Once you get everything figured out you can record the settings and easily return to them for each weight. You could even have multiple settings for different yardages.

I use 110, 125 150 and 168gr loads in my 30-06 - I have a notebook that tells me where to set the elevation using a Stoney Point target knob for the proper zero for each load. There is about a 4 moa difference among the loads. I still shoot a couple of rounds to be sure before hitting the game fields.

Nothing is ALWAYS true in shooting but having different loads hit to the same point of impact is unusual.

wncchester wrote:

Nothing is ALWAYS true in shooting but having different loads hit to the same point of impact is unusual.

well thats often true but Ive got 2 rifles that do.
my zastava .223 hasnt had scope moved at all 12 years of use LOTS of rounds and animals tipped over it groups nearenuf for this kiwi lad. within that playing card size too. Of course my .270win does this its a post 64 (mid 80s) mod 70 lightweight made by that great firm Winchester . some fellas like to get the last possible bit of accuracy from gun/load combos. Im lazy and dont have any problems tipping animals over under 300yrds with my loads and if I get a long shot Ive got time to get out a super duper accurate load fron my waistbag.

7mm...the first thing I would be concerned with is choosing a projectile and weight and developing a load for that projectile and weight. The most important thing is group size before you worry about zeroing. Don't worry about where it is hitting on the target (so long as it is on the paper that is), just develop the load to the point you are happy with the group size. Once you have done that you can then look at zeroing the load to your chosen point of impact (POI).

No doubt you will have two, or maybe three different weight projectiles and loads for your rifle and this is where a quality scope that has turrets that can be zeroed, and good record keeping, comes into its own. After your have worked up your first load and zeroed your rifle/scope combination to it, zero the knobs on your scope. As you develop each load and get your rifle zeroed to it, keep a record of the number of clicks up or down from "zero" for each load. Remember to return your scope to "zero" after each load development. It then becomes a fairly simple matter to adjust your scope to the "zero" for a given load...a quick confirmatory few shots, then your are ready to go.

I know this sounds simple, but it is a fair bit of work, but as English Mike says...a simple chart of sight adjustments should put you on the money in short order with each bullet/load change.

Cheers, Vince

Thanks for the info, I appriciate it.

I have two loads that I use in my 30-06. One is a 220gr. RN bullet that I have set with the scope set to zero at 100 yards. The second load uses 168gr Barnes TSX bullets and it shoots 3" high at 100 yards.
Don

i shoot the nosler 125 ballistic tip with 56gr of rl15 booken 3337 and hitting 3100 lbs 500 yds no problem.