73 grains of 4350 in a 300 Winchester Magnum?

MD

MD

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I'm coming to the end of the two boxes of handloads I made with my buddy's gear for my 300 Win Mag. I won't be getting more of those.

While looking in my ammo locker I came across a box of old handloads that I have that came with the rifle.

They are loaded with 73 grains of 4350, 180 grain CIL Sabre tip bullets with 8 1/2 Mag. CIL primers.

Looking at an old 2nd edition "Metallic Cartridge Reloading" book it lists the maximum load for 300 Win Mag at 71.5 grains of IMR 4350.

I have a Hornady book too and it lists maximum of 69.1 grains of IMR 4350 and a maximum of 69.7 grains of H4350.

My cartridge box does not indicate IMR or H.

Anyway, when I first got my rifle (a Century Arms Centurion on a P14 action) I remember firing a few rounds of that ammunition at the range and the guy next to me asking if those loads weren't a bit too hot as he noticed a flash coming out my barrel.

I can't recall if the recoil was stouter than other loads I was shooting.

Anyway, If I recall correctly, on a hunting trip once when I was getting low on handloads I fired a couple of these at a target and noticed they have about the same POI as my handloads I made so I was thinking of trying them out again if they were safe.

My buddy doesn't load any more and I don't have a press or any of that equipment so it's either use up what I've got or go re-sight the rifle in with a factory load.


So the question is: With either IMR 4350 or H4350 is 73 grains an overload and unsafe?

I have my spent cases on hand and the primers show no sign of bulging or popping out.
 
Does sound a bit hot - I'm in the 67-69 grain range with 190gn bullets.

Maybe give to someone who can pull the bullets and re-use the components?

If you have data that shows that this is above the published max load, then that would be enough for me to scrap 'em personally. Your mileage may vary of course, but you're posting here because you are likely looking for a second opinion...

Regards,
Peter
 
Thanks Peter. In doing some Internet research, I have encountered the occasional reloader in the US reporting using 73 grains but advising caution as well.

FirearmsEnthusiast said:
Does sound a bit hot - I'm in the 67-69 grain range with 190gn bullets.

Maybe give to someone who can pull the bullets and re-use the components?

If you have data that shows that this is above the published max load, then that would be enough for me to scrap 'em personally. Your mileage may vary of course, but you're posting here because you are likely looking for a second opinion...

Regards,
Peter
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I wouldn't use them as they appear - at least on paper - to be over maximum. With that said they "may" be safe but I wouldn't risk body parts on it.

300win.jpg
 
Okay. Point taken.

Thank you very much.

I know from experience that rifle shoots plain Jane Silver box Winchester Super-X cartridges remarkably accurately. Not the best premium bullet in the world, but it works, I'm sure. Probably get a box before my next range day.

Michel
 
You have an old box of handloads on which "some guy" wrote that "They are loaded with 73 grains of 4350, 180 grain CIL Sabre tip bullets with 8 1/2 Mag. CIL primers."

Even if I was on welfare (there's a thread on that), it's one darn sketchy box, and I know what I'd do with them.
 
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I have a pre-lawyer Speer manual ( #8) that lists a max load of 75 gr. of 4350 (doesn't specify which, but likely IMR) with a 180 gr. bullet. Quoted velocity of 3202 fps. I would use them, but you need to make that decision for yourself.

Muzzle flash tells you nothing about pressure.
 
In his book, "Game Loads and Practical Ballistics for the American Hunter" Bob Hagel lists the max load of IMR 4350 in the
300 Winchester Magnum behind a 180 grain Partition at 75.0 grains. However, his caution is to approach from 4 grains below.

So, while that 73 grain load MAY be safe, it is not good practice to be shooting such a stiff load without working up carefully
from below. I would pull the stuff down, personally.

FWIW, a muzzle flash does not necessarily indicate an overpressure load.

Regards, Dave.
 
I seem to remember 300 win mag brass having a wide range of case capacity between brands. IMR 4350 and H4350 have different burn rates. 300wm is tricky to hand load for. I Probly wouldn't shoot them.
 
Asking if you should use them after you've fired some seems like the chicken before the egg.

Really all you need to ask yourself is, do you trust the guy who loaded them to have kept his powder charge accurate throughout all the shells. If so, use them.
 
I run 72.5gr IMR 4350 in my Ruger M77 mk1 .300 behind a 165gr Speer Grandslam with Winchester brass and WLR primers. I worked up from 69 grains and with the resulting average velocity of 3150fps I am not getting any pressure signs. Every rifle is a different beast and what one will shoot and what another will not is exactly the reason why you should be very careful with those loads. Personally, I would pull the bullets, burn the powder and cycle/fire the cases to expend the the primers and save the bullets and cases and start fresh, but that is just how I do things. Rather do this than get a bolt in the face and or worse.
 
'Boo said:
Most of that old data is not pre-lawyer but rather pre-pressure barrel data. They would just load them up until the bolt locked and then back off a grain or so.
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No, no no.
At least from World War One military and factory ammunition was pressure tested and the velocity measured.
In the late 1890s, when Mauser was developing their famous Model 98 action, they designed it to handle 100,000 psi pressure.
 
The thread is about handloaded ammo not factory made.

Yes, factory ammo was pressure tested but most of the old data in reloading manuals was developed the same way most of us work up loads today by visually looking looking for signs of excessive pressure.
 
Cole said:
Every rifle is a different beast and what one will shoot and what another will not is exactly the reason why you should be very careful with those loads. Personally, I would pull the bullets, burn the powder and cycle/fire the cases to expend the the primers and save the bullets and cases and start fresh, but that is just how I do things. Rather do this than get a bolt in the face and or worse.
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The handloads the OP is talking about came with the rifle he's using, so it's highly probable they were worked up in that rifle. Plus, he's already fired some of them. If the bolt's not sticking, and the primers aren't excessively flattened, I would say he's good to go.

The only rifles I've seen actually destroyed by over pressure were mistakenly loaded with fast burning pistol powders.
 
Shooter ----/ said:
Asking if you should use them after you've fired some seems like the chicken before the egg.

Really all you need to ask yourself is, do you trust the guy who loaded them to have kept his powder charge accurate throughout all the shells. If so, use them.
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This.
 
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