Noob here, with noob question: I've read I should set my shoulder bump to -.002" from fire brass length. Well, on checking my die setup, I'm at -.0015"...should I bother chasing that last-.0005"?
300WM sizing
- Thread starter Thor69
- Start date
Nope. This is worth buying though if you are going to stay with belted magnums.
Innovative Technologies - Reloading Equipment
Our patented resizing die can reload Winchester, Remington and Weatherby belted magnums up to 20 times, instead of just 2 or 3 times and the top of the die is a chamber width gauge.
www.larrywillis.com
Thor69 , I’m curious how many times you’ll be able to resize the case before the belt starts giving you issues & are forced to get the Larry Willis die
I'll let you know when/if that happens.
I have a few with loose pockets that are in my "Give to Butch to melt and make artsy_fartsy stuff with" bucket, but none that have swelled at the belt.
I have a few with loose pockets that are in my "Give to Butch to melt and make artsy_fartsy stuff with" bucket, but none that have swelled at the belt.
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I don't know that I will keep it a Magnum. Thinking about rebarelling for 300 PRC.
The Hornady podcast raised some excellent points between the WM and PRC just recently. Even though it's a bit of hype, it's still a good watch. A 300 WM that's been worked over by a good smith with the right reamer is a capable rifle.
Having a bunch of brass on hand that is usable is a huge asset. I paid $600 for 300 pieces of 300 PRC brass from Lapua. My 30" Bartlien barrel was only slightly more expensive. I prefer to not have a belted cartridge, but if you can make it work and you're happy with it?
i have been having similar issues as the op. i got mine sorted out. my 300wm is pushing 3050 fps. saw the willis die here the other day. looks like a viable option. was reading on his site that the belt on the case is pretty much cosmetic and according to him serves no strength or safety purpose. so got me thinking.... why not turn the brass on a lathe and remove the belt? we fire form our brass to head space on the shoulder. my chamber is sort. i have 4 fires on my adg brass and my fl size die won't touch the shoulders but it still chambers fine. just anneal, neck size and mandrel and reload. waiting to see how many fires before it won't chamber . #5 fire on all brass by the end of this month.
from a quick google search.
purpose of the belt on a 300 win mag
The belt on a .300 Winchester Magnum cartridge serves a purpose that originates from the design of older, powerful magnum cartridges
.
Headspacing:
from a quick google search.
purpose of the belt on a 300 win mag
The belt on a .300 Winchester Magnum cartridge serves a purpose that originates from the design of older, powerful magnum cartridges
.
Headspacing:
- Original Purpose: The belt was initially created by Holland & Holland for their .375 H&H Magnum cartridge. This cartridge had a highly tapered case with a shallow shoulder, which made it difficult to headspace accurately.
- Headspacing Explained: Headspacing refers to the distance between the face of the bolt (which pushes the cartridge forward) and the surface in the chamber that stops the forward movement of the cartridge. Correct headspace ensures proper ignition and prevents potentially dangerous malfunctions.
- Belt's Role: The belt on the .300 Win Mag and other belted magnum cartridges acts like a rim, providing a consistent surface for the cartridge to seat against in the chamber, ensuring correct headspace. This allows the rifle to fire safely and accurately.
- Smoother Feeding: In addition to headspacing, the belt also facilitates smoother feeding from a box magazine compared to traditional rimmed cartridges, where the rim of one cartridge could potentially interfere with the rim of the cartridge above it.
- Legacy of the .375 H&H: Many subsequent magnum cartridges, including the .300 Win Mag, were based on the original .375 H&H Magnum design.
- Shoulder Headspacing: As technology advanced, newer cartridges were designed with straighter walls and more defined shoulders, allowing them to headspace on the shoulder like most modern bottleneck cartridges.
- Belt Becomes Less Necessary: For many modern belted magnums with well-defined shoulders, the belt is technically no longer needed for headspacing, as the shoulder alone is sufficient.
- Tradition and Practicality: Despite this, many popular magnum cartridges, such as the .300 Winchester Magnum and 7mm Remington Magnum, continue to feature the belt due to the established infrastructure of firearms and reloading equipment designed for belted cases.
- Provides headspace, ensuring safe and reliable firing.
- Facilitates smoother feeding from a box magazine.
- Is a legacy of the .375 H&H Magnum, the first belted magnum cartridge.
- May not be technically necessary for headspacing in many modern belted magnum designs with well-defined shoulders.
- Belted magnum - Wikipedia
The addition of the belt to the casing prevented over-insertion.
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I wouldn't waste the time getting rid of the belt, just no point. I FL size with .001" bump and use the Willis die when needed.....maybe every 2 or 3 firings. My chamber is long for VLD's and I am running 2900s with 215 Bergers so I am pushing 'em. The belt bulge is real though and using his die will get you much better brass life.
Is your chamber shorter than spec? Should have no issue bumping your shoulders unless your chamber is out of spec short.
Is your chamber shorter than spec? Should have no issue bumping your shoulders unless your chamber is out of spec short.
no cast of chamber but after countless measurements it should be about 2.965 to the lands bto measurement. it is short enough my redding and wilson fl dies don't touch the shoulders of the case. kinda perplexing but she shoots lights out with my load. 215 with h1k.
removing the belt was just a though. a little table top mini lathe and a sunday afternoon lol would solve all the issues that plague the 300wm. but the reality is i've got maybe another 800 rds before barrel is done. then i plan to switch to 300prc.
removing the belt was just a though. a little table top mini lathe and a sunday afternoon lol would solve all the issues that plague the 300wm. but the reality is i've got maybe another 800 rds before barrel is done. then i plan to switch to 300prc.
I went ahead and got the Willis die. I have 200 pieces of Lapua and another 100 of Norma. The other brass is a mix of S&B, FC, etc., and is showing signs of invipient failure. 3 have split the necks sizing after annealing...
i more than likely will get that die also. will resize all the 300wm so i can sell all the 300wm stuff before i switch to 300prc. guessin by the end of this summer my barrel will be just about done.
