Any .300 Weatherby Magnum Reloaders

B

BntBrl

New member
Im getting into reloading to reload for my Weatherby .300 mag. I like it a lot, but its getting expensive. So Ive decided to try reloading. I only go through about 40 rounds a week but at that rate its several hundred dollars a month. I cant see paying that if I can reload the cases a few times.

Ive seen a collet press that resizes the area in the casing just above the banding in addition to the rest of the case needing resizing.

Anyone else here reload the weatherby 300 mag?
 
I reload 300 weatherby. I have never needed to use a die that resizes the area just above the belt. I have a Redding full length sizing die that I adjust to do the minimum resize necessary to make the case fit into the chamber, then reload normally. Bolt action guns usually have plenty to cam action even if the case is a touch tight. Usually the case gets rejected because the primer pockets get loose not because of bulging above the belt. :)
 
I have helped a few acquaintances work up 300 Weatherby loads. I use a standard 2 die set from Hornady. If loading cases for the weapon they were fired in, I usually size to just a fraction above the shoulder and check for fit in the chamber. For base lines, we used Weatherby factory ammo over the chrono. Factory 180gr were 3200fps and 200gr were slightly above 3000f[s

Accuracy loads for 180gr using IMR4831were at or very slightly above max; but the velocities were well below factory by 250-350fps; while H1000 did much better in velocity with 200-250fps below factory. With 200gr Nosler Partition, Retumbo came closest to factory loads (around 50fps slower), while IMR4831 gave the most accurate loads, but 150fps below factory.
 
83grs h-4831,165 nosler ballistic tip, 26 inche barrel 3200fps. mark 5 ss weatherby. 2.5 inch groups at 300yds with 6.6x20 leupold. no trouble with FL RCBS dies. eastbank.
 
My rifle likes the 180 grain Weatherby brand factory ammo. THe 160 grain not so much seems like.

Please forgive my ignorance, but why is the factory loads faster than the reloads? THe same powder isnt available or is it something else I dont know about?

How many people would argue about 150 fps difference when handloading for it?
 
Ammo manufactuerers use powder unavailable to hand loaders. We call those "keg" powders. The stuff we hand load with are called canister powders.
 
I'm getting ready to start reloading for mine... already have a press. I'm looking at getting a set of the RCBX X-Dies to help save the brass... no more trimming too. Should be fun!
 
I was looking at some of those that you dont have to trim. Im not sure how many reloads you can get out of a case, theres still some things that I have to learn first.

I already learned that you shouldnt have to resize near the belt, so that saves me some money. I assume that if you get brass from someone else you would need possibly to resize that area, but sounds like the primer pockets wear out first usually from your own rounds.
 
Well, I ordered the X-Dies... it'll take a while to get them, as .300 Wby isn't a common request in these (apparently)... in the meantime...

What are you guys using for powder in these? I'm looking for a ball powder that will meter good with my powder measure. I will be running around a 150 or 170 grain bullet in my reloads.
 
I have reloaded 50 rounds already. Im using imr4831 and hornady spbt bullets. The groupings I have got are withing 1.5 inches at 100 yards. Im happy with that. The imr4831 isnt a ball type though. I only load 20 rounds at a time so I measure each load by hand to get it exactly the same through my entire box.
 
Respecting an old thread here.

I'm sure we have some experienced 300 wby loaders here, calling on your knowledge.

I have never reloaded a belted cartridge before, and am helping a friend work up a load for his 300 wby.

I loaded 20 to start (he has a TON of brass) for him to try in his Remington 700.

First shot (just over minimum charge) yielded a stuck casing and small stress/pressure crack above belt, as did second. He stopped firing there..

What am I doing wrong? This is once fired brass.

I'm assuming it has something to do with sizing. Any help would be appreciated.

Also - I'm unsure about die set up - Using a new set of RCBS FL dies. Any pointers?

Thanks in advance guys.

-J
 
I load for my .300 Weatherby MkV. I've only used Remington and Weatherby factory cases. In my rifle you have to reduce the loads in the Rem brass. The Weatherby brass has more case volume.
Here's one example using 150 grain Hornady SP's, popular powder for Weatherby's, with Fed 215 primers.
Powder at 87.6 grains--Weatherby case---3343-3357 fps
same Powder at 85.4 grains---Remington case-------3293-3309 fps
So with my powder and rifle a 2.2 grain reduction using Rem brass nearly gets the same velocity as the 87.6 grain load in Weatherby brass.
Also, your Remington 700 may not have as much freebore as a Weatherby MkV and that could raise pressure too. Don't know about Remingtons chambers in .300 Wby?
When I 1st started loading my Wby. I full-length sized with firm contact with the die and shellholder. This pushed the shoulder back more than necessary which lets the case expand forward upon firing and the belted magnum case stretches just in front of the belt. By full-length sizing and pushing the shoulder back every firing, I could only get 3 loadings before there was a stretch mark inside the case and by loading it 4 times the brass looked unsafe to load again. By adjusting the full-length sizing die to only push the shoulder back from fired dimensions by about .002" will stop the brass from stretching so much just ahead of the belt. You need a tool to measure the amount of shoulder set back such as Hornady's Headspace Gauge set or some way to set your dies not to push the shoulder back when sizing. His once fired brass may have already stretched a lot? Use the bent wire feeler method to feel for the stretch mark thats just in front of the belt on the inside of the case wall. Don't load any cases with a deep stretch ring. Also, again, don't use data developed in Weatherby brass in RP or other brands without reducing and working up.
 
I like the 300 wby & I own one, & reload for it.. great caliber & performance. I use it to hunt with, mainly elk & mulies. As far as a target rifle, there are many better choices, performance & economy wise. best to all.
 
Need some more info. I assume factory ammo works?
What is your load? Can you post a Picture of the stressed brass?
 
300 WBY load

Good news....

180 Grain Barnes TTSX
Federal 215M (only) makes a difference!
Reloader 25
use the "hunting load" from Sierra for the 180's
Nosler brass is my favorite for the 300

Use a light crimp to engage the last band on the shank of the bullet but watch for too long of length. First is the rear of the bullet. They don't move ever.

bad news....
The primer pockets get lose after 4-6 loads. For that great power you pay a price. But look at it this way, less than 1 MOA out to 400 yards..
 
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Look at the Entire Process

Consider:

1) After fire forming your bass, neck sizing. It immediately improve my accuracy.

2) weighing your brass for uniformity and load those case in batches that are within 1.5 grains of each other.

3) Do the same with your bullets but reduce your tolerances to .1 grains. That's the limit of accuracy my scale is capable of. Weighing will also address sizes most of the time.

4) trimming all your brass to with 2/1000Th of an inch for exact uniformity in length.

5) Using a seating die that will seat your bullet to within above tolerances.

6) Weighing all your powder loads individually.

7) Try different primer, powders and COAL. All rifles do not like the same load or powder.

8) Keep good records and look for patterns.

The cumulative effect of these steps have help me shoot much more accurately. There are no short cut to producing excellent reloads. But if you enjoy the whole idea of manufacturing in a craftsman like manner a product that you like to use, time will pass quickly.

Good shooting
fxh

PS: My Mark V likes 84.1 gn of imr7828ssc over a Fed 215M Primer using a NP 180 gn bullet.
 
257 here.

Contact Weatherby and ask to buy some (all) of their 300 brass generated by the factory sighting.

I asked several years ago.. Got all kind of funny answers. Very short time later Midway offered 'once fired' Wby brass in several calibers-100 cases per box. I got one box and a friend suggested I should have done more. Week later-all gone and I have never seen since..

Call em..let me know what they say.
 
Pressure signs at start load charges - - - sounds like the case length is too long. If the neck is going into the bore by a minute amount, the bullet cannot move forward without a great deal of pressure . Check case length and trim if necessary.

I have never been able to equal factory ammo velocities by hand loading the 300Wby.
 
Factory

After further inspection, once fired factory loads have a "stretch mark" It's a shiny band above the belt.

The rifle can only use Federal ammo, Weatherby factory loaded gets stuck after firing.

Is this a wicked sloppy chamber or what? From what I have read so far, it seems the issue would be too much headspace?

Let me know what you think, Thanks again, you guys are very helpful.
 
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