.300 Win Mag 208 Amax

[Trinitronman]

Over the past 4 months I've been working on developing a load for my .300 win mag. I have a Savage 110 BA 1:10RH with no modifications. That being said, I have only been reloading for about 6-7 months and started out with the .308. I began trying to load the SMK 190gr over IMR 4350, RL-22 and H1000. For the life of me, I could not find a load with any of those combinations that would group smaller than about 1.5" @ 100yds. Factory 180gr core lokt bullets grouped about the same. I use Remington brass, Federal 215 primers and have tried various seating depths as close as .020" off the lands. I eventually gave up on the 190gr SMK and switched over to the 208gr Hornady Amax. I began the same process starting with H1000. I started with 71.7gr of H1000 and worked up to 76.5 of the same. Hodgdon lists the max load for this combination at 78gr. I loaded up in .3 increments. Out of all of those, the 71.7gr load shot the best. Not wanting to go any higher than 76.5gr, I stopped there and continued playing around with 71.7g at varying lengths. The max length after measuring is 3.620" (touching the lands). I've loaded from 3.340 to 3.600 with little not no noticeable change in POI or accuracy. I currently load this round as follows. Remington brass (I only FL Size when necessary, other than that I neck size), Federal 215 Primers, 3.600 C.O.L.

When it comes to accuracy, I am happy and really had planned on stopping there, UNTIL I started talking to this gentleman at the range. Not being a long range shooter, I had no idea about ES and SD and what it means. For the first time in my life, I rented the Oehler chronograph at the range. I've never seen anyone use it, and I go to this particular range a lot, for the sole purpose of load testing. I randomly grabbed 10 rounds of ammo and sent them flying over the chronograph.

Results:
1. 2808
2. 2768
3. 2761
4. 2764
5. 2799
6. 2789
7. 2776
8. 2785
9. 2774
10. 2776

If I did my math right, and I probably didn't, I come up with:

2780 Avg Velocity
15.20 Std Dev
47fps Ex Spread
3570 Ft-lb

The gentleman I ran in to explained to me that with an extreme spread that high, when and I started to reach out over 500yds that I will run into "stringing" problems and that I needed to get that ES down. I have access to a 2200 acre plot of land and I can place targets well over 1000yds, although I've never shot anything past 147yds.

I do want to shoot further, I'm going to start shooting and 200 and 300 this saturday. I guess the real reason behind this post is to ask questions. So here goes. If I find that this load shoots well at 200 and 300 yards, what can I do, IF I need to do anything, to reduce the extreme spread, and is it really that bad? I do no weigh brass or bullets, do I need to start? Will switching primers do anything at all or is it specifically related to powder charges? I think I know the answer, and that is (in my mind) that it's all a trial an error thing and there is no magical combination, but is there a pecking order?

 

[Barrelnut]

IMO work on the brass first. Remington brass can vary in weigh quite a bit.

1) Sort the brass to +/- 1 gn.
2) Neck tension is important. Make sure the brass you are using all have the same amount of rounds fired. Like a 3 shots fired or all 2 shot fired.
3) Trim the necks to same length each time.
4)Debur the flash holes.

Shoot and see if there is improvement.

5) Anneal the brass. Prep and shoot again. I think you will see some improvement by all this.

6) If improvement is still necessary. Weight sort the bullets into +/- 1 gn. groups. Take each of those groups and sort by bearing length. A-Max bullets are good but they do vary in weight and bearing length more than say Bergers. And that is ok. A-Max bullets can shoot very well at long range. They just need a little more care in the sorting.

7) Still got problems? Look at the consistency of the powder charges and consider trying another primer. The Federal primers are very good however.

Other thoughts:
-Don't start speed test with a clean barrel. Get about 6-10 rounds thru the barrel after cleaning. Then start the speed test. It takes the barrel a few shots to settle down after cleaning.

-Don't let your rounds set in the hot chamber very long. Try to fire with 10 seconds or so of loading the chamber.

- Keep the powder somewhat level in the cartridge when you chamber the round. As in, don't have all the powder at the front of the cartridge on one shot and all of it at the back on the next shot. Load single round, don't shoot from the mag during testing.

 

[Lone Hunter]

TM, You might want to look at this site. These guys shoot a lot of long range and 300 WM and 300 WSM. Make sure you look at load data carefully before you load.

Sniper's Hide - Long Range Shooting, Precision Marksmanship, Gear Testing & Reviews - Scout Front Page

 

[MagnumManiac]

After shooting the 300WM in competition (1000yrds) for several years, it really likes to be pushed hard, and bullets like the A-Max may work best when they are touching the lands or just off, say .005"-.010".
I use Lapua brass for comp, have a large number of them, but Norma, Win and Rem all work with a little prep. Weight sorting to 1gr may or may not be necessary, trimming to equal length is paramount, de-burring and uniforming flash holes is necessary, as is chamfering the inside and outside of the case mouth.
Try loads with both Fed215's AND WLRM primers, there will be a preference, trust me.
With powders like H1000, I swirl the charge to get consistant powder packing, it is important because it affects ignition and gives lower SD and ES figures.
Swirling the charge involves dumping the powder into the scale pan, using a funnel, pour the powder at an angle so the powder circulates around the axis of the funnel, like a tornado, this allows a lot more time for the powder to settle. If you dump 2 shells side by side, one with and without swirling, you will clearly see the difference.
If you have any questions regarding this, don't hesitate to ask.

Cheers.
gun)

 

[HARPERC]

Sounds like you're having fun that's the main thing. All good advice so far.

My 2 cents is look at it as a system, you don't mention how you're setting up to shoot, which scope you're using, and finally chronographs have their limits as well.

Separate subjects in themselves, but worth thinking about. Search bar very upper right corner will lead you to good threads on each.

Good Luck!

 

[Canadian Bushman]

After shooting the 300WM in competition (1000yrds) for several years, it really likes to be pushed hard, and bullets like the A-Max may work best when they are touching the lands or just off, say .005"-.010".
I use Lapua brass for comp, have a large number of them, but Norma, Win and Rem all work with a little prep. Weight sorting to 1gr may or may not be necessary, trimming to equal length is paramount, de-burring and uniforming flash holes is necessary, as is chamfering the inside and outside of the case mouth.
Try loads with both Fed215's AND WLRM primers, there will be a preference, trust me.
With powders like H1000, I swirl the charge to get consistant powder packing, it is important because it affects ignition and gives lower SD and ES figures.
Swirling the charge involves dumping the powder into the scale pan, using a funnel, pour the powder at an angle so the powder circulates around the axis of the funnel, like a tornado, this allows a lot more time for the powder to settle. If you dump 2 shells side by side, one with and without swirling, you will clearly see the difference.
If you have any questions regarding this, don't hesitate to ask.

Cheers.
gun)

Why is trimming to equal length so important?

 

[Barrelnut]

I think what we are getting at here is consistency in the physical loads will lower ES/SD. Consistent neck tension, neck length, case volume, and ignition all play a part. Consistent seating depth can also play a role. All needs to be consistent.

 

[jonthomps]

I think what we are getting at here is consistency in the physical loads will lower ES/SD. Consistent neck tension, neck length, case volume, and ignition all play a part. Consistent seating depth can also play a role. All needs to be consistent.

^^^ This.

 

[MagnumManiac]

Why is trimming to equal length so important?

It effects how the bullet is released, if uneven, the mouth will be tighter on one side, as you know, the case mouth doesn't expand fully at the end, it stays turned in slightly, this may tip the bullet to one side because it drags against the longer side of the case mouth.

Cheers.
gun)

 

[Canadian Bushman]

It effects how the bullet is released, if uneven, the mouth will be tighter on one side, as you know, the case mouth doesn't expand fully at the end, it stays turned in slightly, this may tip the bullet to one side because it drags against the longer side of the case mouth.

Cheers.
gun)

Ahhh i see. I misunderstood your previous post. Yes i agree this is important.

 

[el matador]

I agree with earlier posts about consistency, especially weight sorting brass. You can do a lot to lower your ES, but the fact remains that some loads just have a higher ES than others. I load for 3 different 300 WMs, all shooting the 208 Amax with H1000. One likes 76.0 grains, another 76.8, and the third prefers 78.0. The 3 rifles shoot 3/8, 5/8, and 1/2 MOA respectively. The loading data gives a max charge of 78.0 grains with a seating depth around 3.4" if I recall. You are seating your bullet quite a bit further out than the loading data indicates. That creates more room in your case so you can use more powder before reaching max pressure. Nothing wrong with using less powder if that load works for you, but you do have the option of finding another accuracy node in the 76-78 grain ballpark. That load may or may not have more consistent velocity.

 

[Trinitronman]

IMO work on the brass first. Remington brass can vary in weigh quite a bit.

1) Sort the brass to +/- 1 gn.
2) Neck tension is important. Make sure the brass you are using all have the same amount of rounds fired. Like a 3 shots fired or all 2 shot fired.
3) Trim the necks to same length each time.
4)Debur the flash holes.

Shoot and see if there is improvement.

5) Anneal the brass. Prep and shoot again. I think you will see some improvement by all this.

6) If improvement is still necessary. Weight sort the bullets into +/- 1 gn. groups. Take each of those groups and sort by bearing length. A-Max bullets are good but they do vary in weight and bearing length more than say Bergers. And that is ok. A-Max bullets can shoot very well at long range. They just need a little more care in the sorting.

7) Still got problems? Look at the consistency of the powder charges and consider trying another primer. The Federal primers are very good however.

Other thoughts:
-Don't start speed test with a clean barrel. Get about 6-10 rounds thru the barrel after cleaning. Then start the speed test. It takes the barrel a few shots to settle down after cleaning.

-Don't let your rounds set in the hot chamber very long. Try to fire with 10 seconds or so of loading the chamber.


- Keep the powder somewhat level in the cartridge when you chamber the round. As in, don't have all the powder at the front of the cartridge on one shot and all of it at the back on the next shot. Load single round, don't shoot from the mag during testing.

Barrelnut

Thank you!! So the brass that I have been using is literally on its 6th firing counting the one from factory new. Once I found this load it served as my c.o.l testing brass for 3 loadings and again for 2 additional loadings of my 3.600" I'm going shooting brass. It has been fl sized twice and neck sized the remainder and trimmed after every loading (if it exceeds 2.620, which is also the length I trim them to.)

It is probably time that I switch to newer brass. I've done everything that I can think of to the cases except actually weigh them individually and debur the flasholes. I will do that on my next round of brass. I think honestly my interest in the pursuit (that I didn't know I had) of accuracy will never bring me to the annealing stage.

I individually weigh each powder charge twice, and load each one by hand without the use of a trickler or a powder dump. The H1000 is so big I drop it with tweezers to get the two scales to read the same. Both scales a balance beam type rcbs, i do however use a digital scale to measure to within a few grain of the final load before finishing them up on the mechanical scales.

 

[Trinitronman]

After shooting the 300WM in competition (1000yrds) for several years, it really likes to be pushed hard, and bullets like the A-Max may work best when they are touching the lands or just off, say .005"-.010".
I use Lapua brass for comp, have a large number of them, but Norma, Win and Rem all work with a little prep. Weight sorting to 1gr may or may not be necessary, trimming to equal length is paramount, de-burring and uniforming flash holes is necessary, as is chamfering the inside and outside of the case mouth.
Try loads with both Fed215's AND WLRM primers, there will be a preference, trust me.
With powders like H1000, I swirl the charge to get consistant powder packing, it is important because it affects ignition and gives lower SD and ES figures.
Swirling the charge involves dumping the powder into the scale pan, using a funnel, pour the powder at an angle so the powder circulates around the axis of the funnel, like a tornado, this allows a lot more time for the powder to settle. If you dump 2 shells side by side, one with and without swirling, you will clearly see the difference.
If you have any questions regarding this, don't hesitate to ask.

Cheers.
gun)

I'll see if I can get my hands on a sleeve of 100ct of WLR primers. All I seem to find around here, when I find them are Federal and CCI.

When shooting from 3.340 to 3.600 I honestly noticed no difference in poi. Do you think that going back to 3.340 or maybe somewhere in between 3.340 and 3.600 will aid enough in powder packing to have any impact on the consistency of the charges? I don't mind terribly pushing the bullet harder, I was originally concerned with barrel wear, but now I really don't care as I'm having way too much fun with this. All my rounds are loaded by hand with a funnel, I will give the swirling thing a try too.

 

[MagnumManiac]

If your loads are compressed a fair amount, which they will be with 208 A-Maxs, the seating depth will affect the burn, if you can load to 3.6", then stick with it.
In my own 300, I can't load any longer than 3.550", I'm into the rifling at this length.
Your rifle almost has a Weatherby length throat, you should be able to load a bit hotter for more velocity with lower pressure.
The idea of powder packing is to have the powder as low down the case as possible, if an as dumped charge fills above the neck/shoulder junction and is loosely filled, it can compress at different ratios when the bullet is seated, some being pushed between the bullet and shoulder tightly, while others will be loose in this area. When you settle the powder tightly, so that the level in the case is the same with every case, it burns more consistently and CAN REDUCE ES and SD dramatically, fine tuning also seems easier, as it doesn't take much tweaking to get really good groups.

Cheers.
gun)