Sighting In .338 win mag

bigbore14

bigbore14

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Looking for advice.

I am getting conflicting advice as to the correct way to sight in my hunting rifle.

I reload my own ammo.
I was told the best way is to load several differnet powder charges. With the same bullet and see what shoots best in the gun. ( THis is what I wanted to do)

Shoot in groups of 3 and see what loading (Powder) gives the best grouping..........Correct?

However things changed.

I was out at the range this past weekend, a friend with seemingly lots of shooting experience???, and his theory is max load all your shells, and dial it in that way......see where it shoots and make the changes to your scope...

So I did....breaking my theory about finding the best load..I loaded a bunch of of different powder charges from (69.0 - 74.5 Grains), most of which i never shot that day.

He states that the powder charge only chages the velocity of the bullet, nothing else, with does not really matter if your shots are going to be less than 200 yards ( as he recommends for Grizzly - he says < 80 is best)

His theory is get the gun shooting exact at 25 yards. (A little movement at 100 yards and you never know if it is you or the gun)
So I did ...I was punching paper through the same hole at 25 yards.

Then I tried 100 yards. And I was shooting 1 - 1 1/2 inch groups.
Many shots went through the previous hole. But approx 3 to 3 1/2 inches High


I was shooting load of 74.5 gn H4831sc and 225 gn hornady bullets CCI mag primers. What is the best way to get a hunting rifle sighted in ? I am planning a grizzly hunt in late May and don't want to miss !!


What should I do ?

Suggestions Please..

Thanks
 
Zero the gun at what you consider will be your 'average' shot distance. 200 is pretty accurate, I would guess.

Your friend is incorrect when he says the charge only changes the velocity. Some loads are MUCH more accurate than others, and accuracy and velocity will change.

Zeroing at 25 yards ONLY should be criminal. IF you have a grizzly tag, you better damn well KNOW where your load is shooting at EVERY distance between 25 yards and 400 yards. Practice every day for a MONTH before your trip.

Please, don't blow your shot at a grizz because you 'thought' your rifle would shoot accurately at a given distance!
 
Most books say 2" high at 100 yards is the place to be.
I am using a straight 4x scope.
100 Yards is not the easiest to be accurate when looking through a straight 4 power.
It's really hard to be exact ...to be confident that the scope is in the exact same place as the previous spot....without having to buy a new scope would there be any options at say 50 yards instead ??
thanks
 
if you look at a loading table , you should see TWO columns: one is first crosses line of sight at x yards- this is the BEGINNING of the "rainbow" of the flight of the bullet- ie where you need to sight in at- the other column is the MAXIMUM POINT BLANK RANGE-
this is where the bullet has only 6 inches deviation from the target- it'll be within that parameter all the way out to that yardage- in other words, that bullst will strike somewhere within that 6 inch circle if you sight in at the first range
second , your freind has given you some VERY POOR ADVICE on loads - every rifle is different and you need to build up the loads until you see pressure signs, and stop there
you can't arbitrarily pick a powder and top end load out of the book - you may have a lower pressure rifle, and a hot load and a low pressure rifle spells disaster
the whole point of reloading is load development, and that means SAFETY AS WELL AS FINDING THE " SWEET SPOT" in loads for your rifle-
my grizzly rifle is a bar and my loads are 275 grain speers( which you can't get anymore) 70 grains of imr 7828( which is the bottom load in the table) and a cci magnum primer- it's sighted in for 350 yards and wears a 4x12x40 mm scope
 
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Your friend's advice is not sound advice. You were on the correct track to begin with, as far a load developement goes. The powder charge changes velocity, pressure and also felt recoil. Find the load that work best in your rifle. The extra 100 fps you might gain by loading to the nuts might just mean a bullet that misses your bear 100 fps faster. With a good hit the bear won't know the difference if your bullet is 100-150 fps slower getting there.
If your 4X scope isn't enough try putting a black square on a white background and shooting the 4 corners. Don't go by what the books say about bullet drop, actually go out and shoot those distances and find out where your rifle shoots with your load.
 
Has your friend ever encountered a little know law called the Law of Gravity? Sounds like he missed that day in grade 2. If you hold an empty casing in your hand and drop it at the exact instant you pull your trigger, that empty case and the bullet you just fired will hit the ground at exackly the same instant. All we can do is to try to put the bullet further down range before it does. Your friend is going to blow up a rifle someday. Each rifle/cartridge combination is different. You just don't load one load and expect it to work in all your guns chambered for that cartridge.

Scott
 
If loading for hunting big bear, my suggestion differs a little bit, pick 1 or 2 bullets that you plan on using for the biggest animal you plan on hunting. Develop your most accurate load with that bullet using 3 shot groups at 100 yds. To save ammo you can sight in at 25 yds first, moving to 100 yds when on paper, it is much easier to move your crosshairs when you are shooting a decent group and are not all over the target. Sight 2" high at 100 and try 200 yds or longer, and as someone else said, get real comfortable with your gun/scope/load at the diff. ranges. And oh yea, enjoy yourself, that's why we're all doin' this, and enjoy your hunt as well......Ben
 
Good advice above.

Your friend's advice could get you killed.

First, the max in the book refers to THEIR rifle, not yours. It could be way too hot in your rifle. Your rifle could have a shorter, tighter throat, a tighter neck, etc.

Second, when hunting dangerous game, reliability is critical. If you fire a shot and it won't extract because the case is stuck or because you blew the extractor off, you are left holding an expensive club...

There are three issues you face. Which bullet? What load? Is it sighted in?

A bear has very big bones, heavy muscles and deep fat. A grizzly is one of the few North American animals where a 338 Mag is not too much gun. But if it was me, I would use a bullet no lighter than 250 gr. You need a well placed, strong deep penetrating bullet. There are places to save $50 – but this is not it.

What load is most accurate? You had the right idea. Install a 9X or so scope (borrow one if you don't have one) for accuracy testing. Load 3 rounds of 71 gr and increments in 0.5 steps, up to 74 grains. Shoot the 3 shot groups, and then let the barrel cool. A warm barrel would tell you nothing about grouping or zero. I use a wet towel to speed cooling.

If you cannot switch scopes for testing, make a better aiming mark to aim at. Get some good sized targets, such as the big ones at the pistol club. A sheet of newspaper might work in a pinch. The targets are put up backwards - white side facing you. Make some 8" squares out of black construction paper (buy it at the dollar store.) Put the black square up as an aiming mark. Aim at one corner and fire 3 shots. Go forward, circle the group and note the load on the paper. By the time you get back to the rifle, the barrel should be cool enough for the next group. You can click some adjustment into the scope if you want. Fire the next group, aiming at a corner such that the new group should not be near the first one. Go forward, circle the group, etc.

I use a felt marker to write the powder charge on each case, so I can examine the cases later and be sure how much powder was in each case. As you shoot the groups, check the cases for ease of extraction and signs of excess pressure.

Choose the load that is best, without any pressure.

A 4X scope is an excellent hunting scope for everything except long range (over 250 yards). I have no idea what kind of terrain you will be in. Most of my hunting experience has been with a 2.5 or 3X scope or a variable set as low as it will go. (Eastern Canada. I know the West can be different.)

After you have found the best load, you need to install the 4X scope, if you used a bigger one for load testing. Before you do that, re-install each of the base screws with a dab of blue LokTite. Once a scope is installed, you won’t be able to check those screws again.

If you are shooting your groups with the 4X scope, adjust each group so that you get your groups about 2” high. Unless your hunting is at longer ranges, you should be able to place a shot perfectly, without having to think about trajectory, from 10 to 150 yards.

If you used a bigger scope, and now have to zero your 4X scope (which, I think, was part of your original question) fire a shot at 25 yards. Make and adjustment to move the bullet hole to point of aim. At 25 yards you will need to click it 16 clicks to move it an inch. I typically fire a second shot, to confirm I moved it in the right direction, then switch to my 100 yard (or 200 yard) aiming mark. If the bullet was close to point of aim at 25 yards, it will be close to where you want it at 100 yards. But this is a way to save ammo by making sure you are on paper at 100 – not a substitute for sighting in at 100yards.

A black 8” square is a perfect aiming mark with a 4” scope. Aim at one of the corners.
 
buy some factory ammo and put your impact +1-2" high @ 100 yards and test point of impact at different ranges from 25,50,100,150,200.

stick with factory ammo for the time being, there is alot of good ammo out there like Federal Premium. Going after dangerous game with unproven handloads which could stick in the chamber due to overpressure could get you hurt bad, work up a proper load in the summer the right way.
 
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