Futile exercise with 300 Win Mag loads?

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I'm currently working up a good hunting load for my son's Browning X-bolt in 300 Win Mag (deer and elk). We're loading Barnes TSX 180gr bullets over various loads of Re22 powder. The load that stands out for accuracy is 72.0gr of Re22, which produced 1/2" groups at 100 yds and 1 1/2" groups at 200yds. All groups start to open up at each increment less than 72.0gr and at all increments greater than 72.0gr.
73.0gr produced a 1" group @ 100yds
74.0gr load produced a 1 1/2" group @ 100yds.
I was hoping to get closer to "factory" velocities with 75.0, 76.0 and possibly 77.0 gr loads, but will I just be wasting my time and components? I've read about "nodes", so is there a possibility that the grouping may start to tighten up again with the higher loads?
We've been without a chrono, but I'm guesstimating that the 72.0gr load is producing a MV of about 2950fps.
Should we just call it good and go with the 72.0gr load?
 
I would definitely load it up hotter. This cartridge seems to perform best at or near max. If memory serves, Barnes data even calls for loading up to 77 or 78 grains of Reloder 22 with a 180 Barnes bullet.

As you've discovered, it also has another sweet spot at about 7-10% below max. This has been my experience.
 
If max loads are up around 78gr, than you are barely at a typical starting load with your 72gr one. I would definitely look for another node much closer to max.


Mark
 
Get or borrow a chronograph. Barnes gives 73 grains as the max load with RL22, at least in the #4 manualand their website. God only knows what they may have printed/suggested at other times.

Barnes data is/was some pretty screwed up s**tt. There was a point in time when they claimed that the TSX grooves allowed raiseing the charges a couple grains over loads built around cup and core bullets. Now they list their loads considerably below others.
 
p-17 said:
I would definitely load it up hotter. This cartridge seems to perform best at or near max. If memory serves, Barnes data even calls for loading up to 77 or 78 grains of Reloder 22 with a 180 Barnes bullet.

As you've discovered, it also has another sweet spot at about 7-10% below max. This has been my experience.
Click to expand...

The Barnes data that I have from their website shows a maximum load of 73.0gr of Re22, yet most other bullet manufacturers reloading data for their bullets show a max of up to 77.0gr. I've been hesitant to load much higher than 73.0gr for my son's rifle (he wants to stick with Barnes bullets), but did load 75.0gr under Speer Grand Slams for my own Savage 300 Win mag.
There were no signs of over pressure.
 
mmattockx said:
If max loads are up around 78gr, than you are barely at a typical starting load with your 72gr one. I would definitely look for another node much closer to max.


Mark
Click to expand...

Thanks Mark......There's no doubt in mind that the 72.0gr loads will work just fine on deer and elk in 300 Win Mag, but a max loaded .308 would probably do the same job. ;)
 
Dogleg said:
Get or borrow a chronograph. Barnes gives 73 grains as the max load with RL22, at least in the #4 manualand their website. God only knows what they may have printed/suggested at other times.

Barnes data is/was some pretty screwed up s**tt. There was a point in time when they claimed that the TSX grooves allowed raiseing the charges a couple grains over loads built around cup and core bullets. Now they list their loads considerably below others.
Click to expand...

I foolishly sold my chrono after I quit IPSC. One of my son's collegues has one and will be bringing with him for our next range visit.
Otherwise, we're shooting in the dark as you know.
Accuracy doesn't lie, however, which is why I'm loath to move on after getting such great results with the 72.0gr load. Must be getting old. :D
 
I found the most accurate "factory" load in my 300 winmag Savage 111 to be the Federal Premium 180gr's which use Nosler Accubond bullets. Quite accurate.
As a result, I'm going to try some 180gr Nosler Accubonds at the higher loads using Re22 powder, starting at 73.5gr and working up to the max listed 75.5gr.
Nosler's manual also notes that the 180gr Accubonds over 75.5gr of Re22 was the most accurate load tested (3118 fps). I realize that every rifle's unique, but we'll see how it performs.
 
how much more than 2950 do you think you can get out of a 180/300 win?
In any case I prefer to use a chronograph to find the max load.
 
jeff270 said:
how much more than 2950 do you think you can get out of a 180/300 win?
In any case I prefer to use a chronograph to find the max load.
Click to expand...

Well, that was the point of my post. :) I'm probably more than just a bit optimistic with my guess at the MV of the 72.0gr loads, but I'll know for sure at the next range outing.
I have never worked up a load before without the use of a chrono (essential in IPSC). My son's probably more enthusiastic about finding the "perfect" load for his Browning than I am for my Savage.
 
trykillthis said:
I have been using 66.7gr IMR 4350 with the barnes 180 tsx at 3.325 OAL. Gives me 3/4" groups in my Savage 111.
Click to expand...

As I had quite a bit of H4350 (which is now the same powder as IMR4350 if Hodgdon is to be believed), I tried 69.0gr with the 180gr Barnes TSX bullets. I recorded that it was a "Good Load!", achieving just under a 1" group. Good enough to keep this old guy thrilled with his marksmanship. :D
 
For me, the "control load" in this cartridge is always 73 grains of IMR 4831 behind any decent 180-grain bullet. It always gives decent accuracy and about 3,000 fps velocity. I often use that as a starting point when assessing the loading potential of a .300 Win. Mag rifle. Some loads give better accuracy, some better velocity -- and some even a better combination of the two. But if this combo doesn't give me approximately 1 inch groups at 100 and 3,000 fps, then I know that something is wrong with the rifle.

FYI, your load of 69 grains of IMR 4350 behind a 180-grain bullet is also the classic 1,000 yard Wimbledon Cup load that dominated for decades.
 
p-17 said:
For me, the "control load" in this cartridge is always 73 grains of IMR 4831 behind any decent 180-grain bullet. It always gives decent accuracy and about 3,000 fps velocity. I often use that as a starting point when assessing the loading potential of a .300 Win. Mag rifle. Some loads give better accuracy, some better velocity -- and some even a better combination of the two. But if this combo doesn't give me approximately 1 inch groups at 100 and 3,000 fps, then I know that something is wrong with the rifle.
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That's good to know, thanks! I have no previous experience with the .300 Win Mag cartridge, so this is uncharted waters for me. I have worked up very nice loads for .303 Brit, .308 Win, .30-'06 and (for my grandson) 7mm-08. I also went straight to H4350 and Re22, but I would like to try IMR4831.

p-17 said:
FYI, your load of 69 grains of IMR 4350 behind a 180-grain bullet is also the classic 1,000 yard Wimbledon Cup load that dominated for decades.
Click to expand...

Well there you go. There is truth to the old adage "Even a blind chicken can find a kernel of corn once in a while". :D
That load shot as well as the Federal Premium factory ammo that I had with me.....a bit better, in fact.
 
Are you looking strictly for a sub-200 yard load or will you be going further out? The 300 win mag only starts to show her true potential at distances of around 400 yards or better. You're definitely on the low end of the powder charge.

-Jason
 
Used a 300WM extensively (1000s of rounds) and got my best accuracy at max always, in three different rifles. All three of these guns gave me best accuracy and velocity with a 180 gn and IMR7828. RL22 wasn't around yet but I have found it to be a great powder lately. Keep going up the scale using due caution, of coarse, and watch for the signs we loaders all know so well. I suspect your best groups will occur just before ejector marks appear.
My experience anyway.
 
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