300 WM Dies/Brass Prep

[Brydawg512]

Hello all,

I'm finally beginning to purchase the remainder of the equipment to get into reloading for my 300 WM. In a previous thread, I obtained a lot of great information about things I may need.

I have a few more specific questions I am curious about:

1) For brass resizing, I understand I need a FL sizing die. Since I won't be neck turning at this point, my understanding is I need a collet to properly resize the neck to obtain a .02 neck tension. Do I also need to use an expander mandrel after sizing with the collet, are they used in conjunction with one another, or is it one or the other?

2) Is a collet for resizing the body something I should consider?

3) Annealing — I've heard conflicting things, some say they never anneal others say the anneal every x number of firings, some every during. Thoughts/opinions?

4) CBTO measurement — can I still use a normal comparator to measure, considering headspace is measured from the belt to ogive?

Lastly, to ensure I understand the resizing process properly:

When resizing, what exactly is being resized? I understand that I am bumping the shoulder back to allow for proper fit in my chamber, but what else is being sized? I understand the case mouth is trimmed afterward to fit within SAAMI specs.

I apologize for my ignorance and can ensure everyone here I am not beginning reloading until I have a much further understanding of everything.

Thank you all in advance.

 

[Reelamin]

You can go as detailed as you want in reloading. I just finished up a 300WM (Factory Savage 10T-SR) and it shoots 5 into 1's and low 2's. I just flat don't do detail as if I am world record setting and days of case prep and loading 20 rounds. Some do I just don't see the need. Killed my buck this year one poke...480-500yds as last range I had was 485 and he moved around a little. Hit about 3" left of exact hold location. That rifle shoots 6's to high 7's.

I just finished up a 300WM (Factory Savage 10T-SR) and it shoots 5 into 1's and low 2's.

1. Loaded them with the same RCBS 300WM dies I purchased in the early 90's. Have 3 fires on some of the brass and still shoots just as good. I bump the shoulders 2K.....that is it!!!
2. Not in my world
3. I have a basic annealer.....and don't anneal every time. If I do anneal it may be 5 firings or 1 because when I think one batch needs it I anneal all the empty fired brass I have.
4. What?
5, Neck, shoulder, some body.

Ignorance is fixable and you are working on it.

 

[Brydawg512]

You can go as detailed as you want in reloading. I just finished up a 300WM (Factory Savage 10T-SR) and it shoots 5 into 1's and low 2's. I just flat don't do detail as if I am world record setting and days of case prep and loading 20 rounds. Some do I just don't see the need. Killed my buck this year one poke...480-500yds as last range I had was 485 and he moved around a little. Hit about 3" left of exact hold location. That rifle shoots 6's to high 7's.

I just finished up a 300WM (Factory Savage 10T-SR) and it shoots 5 into 1's and low 2's.

1. Loaded them with the same RCBS 300WM dies I purchased in the early 90's. Have 3 fires on some of the brass and still shoots just as good. I bump the shoulders 2K.....that is it!!!
2. Not in my world
3. I have a basic annealer.....and don't anneal every time. If I do anneal it may be 5 firings or 1 because when I think one batch needs it I anneal all the empty fired brass I have.
4. What?
5, Neck, shoulder, some body.

Ignorance is fixable and you are working on it.

Thank you for all of your insight. I appreciate your understanding.

As for #4, I have heard that on a belted magnum, I am to measure from the belt to the ogive, compared to a bottleneck round, where I would measure from base of cartridge to ogive… or am I just misled? To obtain CBTO with a belted cartridge, would I still measure from the base of the casing to the ogive?

 

[Onehorse]

Thank you for all of your insight. I appreciate your understanding.

As for #4, I have heard that on a belted magnum, I am to measure from the belt to the ogive, compared to a bottleneck round, where I would measure from base of cartridge to ogive… or am I just misled? To obtain CBTO with a belted cartridge, would I still measure from the base of the casing to the ogive?

When getting started, keep it simple. I have been using the same equipment for over fifty years. I clean my cases in a tumbler, use spray on lube, full length resize, measure the case lengths and trim if necessary. Reclean in the tumbler. Prime, charge and seat the bullets using recommended recipes from reloading manuals. That's basically it. You can go down all kinds of rabbit holes, and much of that might be important for competition target shooting, but not so much for the recreational shooter or hunter.
Here are the kind of groups I get. Good luck, keep it simple and have fun.

 

[Old Rooster]

Don't worry about the belt,measure CBTO from the bottom of the cartridge to the ogive.Way more accurate than measuring from the bullet tip to the bottom of the case.
Your getting some great advice here but ask if you have any questions.

 

[Bang4theBuck]

Hello all,

I'm finally beginning to purchase the remainder of the equipment to get into reloading for my 300 WM. In a previous thread, I obtained a lot of great information about things I may need.

I have a few more specific questions I am curious about:

1) For brass resizing, I understand I need a FL sizing die. Since I won't be neck turning at this point, my understanding is I need a collet to properly resize the neck to obtain a .02 neck tension. Do I also need to use an expander mandrel after sizing with the collet, are they used in conjunction with one another, or is it one or the other?

2) Is a collet for resizing the body something I should consider?

3) Annealing — I've heard conflicting things, some say they never anneal others say the anneal every x number of firings, some every during. Thoughts/opinions?

4) CBTO measurement — can I still use a normal comparator to measure, considering headspace is measured from the belt to ogive?

Lastly, to ensure I understand the resizing process properly:

When resizing, what exactly is being resized? I understand that I am bumping the shoulder back to allow for proper fit in my chamber, but what else is being sized? I understand the case mouth is trimmed afterward to fit within SAAMI specs.

I apologize for my ignorance and can ensure everyone here I am not beginning reloading until I have a much further understanding of everything.

Thank you all in advance.

1. You do not use an expander mandrel after the neck collet die. The expander is better suited for use with other dies that size the case by sizing the exterior of the neck. The expander mandrel insures that you are controlling the neck interior dimension. The collet does the same thing.
2. There is no such thing as a collet die that sizes the body. What you should consider is a Redding body die. This sizes the body of the case and is used to push the shoulders back. It does not touch the neck. That work is done by the neck collet die. This is an excellent (and inexpensive) approach to controlling the two critical things.
3. There is always someone that will say this step can be forgone, nnd that is true. However there will absolutely be negative affects on brass life, and some reduction is consistency of the final sizing of brass due to spring back. Brass gets work hardened with use. If you don't anneal, the work hardening will have adverse affects. How often you anneal (every firing versus every 2 or 3) is debatable, but annealing or not annealing really isn't if you care about brass life a d consistency.
4. I think there is some confusion about how to measure finished ammo, and seating depth. Let me clarify. CBTO (cartridge base to ogive) is pretty self-explanatory. You need to put your 30 cal bushing in your comparator, and then using you calipers, measure from the base of the case (not the belt) to the ogive of the bullet. This final dimension is specific to your rifle and should be determined by one of two things. 1. What distance you want the bullet from the point of engagement into the lands. .020" is a generally accepted starting point when doing load development. 2. Your magazine length. If you try to put your bullet close to.the lands of the rifle, it is possible that the resulting cartridge length will not properly fit in your magazine (too long).

Understamd that every time you fire a case, the pressure from the ignition (50-65k psi) swells the case and forms it to your specific chamber. The sizing process reshapes the case to near factory specs so that it fits back in the chamber, with proper clearances. Here are the actions that are performed when resizing
**. If using a full length sizing die, the die pushes the exterior of the case body back into spec after being swelled from firing. It pushes the shoulders back from the case expansion that happens when firing (the case grows). It also pushes the exterior of the neck back to a point that is smaller than final dimension, amd then when you pull the case back through the expander button, if final sizes the interior of the neck.
**if using a neck.collet die and a body die, the same functions happen with two different dies. The neck collet die does a better job of sizing the brass without worki.g the brass too much, in my opinion..

PM with any further questions..

 

[GrayCreed]

1. Once you full length resize, you aren't going to be doing anything for neck tension unless your full length die is a bushing die. There really is not a whole lot of point to this as consistent neck tension is more important than a specific setting. Most factory standard dies will achieve this if you are using a good press and lubricant is consistent from case to case.
2. Wait and reload a couple and see first, that is mostly needed in cheaper rifles where the chamber is oversized at the back or if you are running too much pressure.
3. With a big case like 300wm you will increase your case life by annealing but it's not a requirement to get started.
4. No, just no. The parent case 375h&h headspaces off the belt. The 300wm is supposed to headspace off the shoulder
5. You can resize just the neck,... But ONLY if you buy a "neck sizing die" do not try to neck size by "backing off" your full length die- your cases will "grow" in the shoulder area and eventually not fit in the gun. If full length resizing make sure you measure the headspace of the case after you fire the first couple rounds. You do not want to reduce the shoulder more than .002" from that measurement.

 

[highfinblue]

I would also encourage you to buy a good reloading manual and read through the process that is there in print. As stated in previous posts for the guy just wanting to target shoot a bit and hunt with his own handloads all the extra stuff is not necessary. I have a couple of rifles I do a bit extra with, but I'm trying to hit things a long way off with those; for my rifles that will never shoot past 400 yards I do the same things I did when I started loading forty years ago. I full length resize with dies from several manufacturers, Hornady, RCBS, Redding, and I even own some Lee dies, they all work for typical shooting. It is not hard to get a rifle to shoot under 1 MOA nowadays, and unless you're shooting distance, that's good enough.

 

[5gauss]

When getting started, keep it simple. I have been using the same equipment for over fifty years. I clean my cases in a tumbler, use spray on lube, full length resize, measure the case lengths and trim if necessary. Reclean in the tumbler. Prime, charge and seat the bullets using recommended recipes from reloading manuals. That's basically it. You can go down all kinds of rabbit holes, and much of that might be important for competition target shooting, but not so much for the recreational shooter or hunter.
Here are the kind of groups I get. Good luck, keep it simple and have fun.

Yes...not rocket science for the hunter just pretty basic. Have loaded for 50 years myself. I do use the special collet die for belted magnums every other loading or so to squeeze the case near the head...cases may last longer....yes, have fun with it...follow the books/steps..be safe

 

[highfinblue]

I might add some folks will try to get the absolute most out of a cartridge and as long as it is safe with no pressure that is an advantage of reloading; however, some folks push the envelope way too much. I had a friend that had his .270 Winchester loaded so hot it blew primers out every time he pulled the trigger. I was young and dumb at the time, but I still told him I wasn't going to shoot with him because I didn't want to see him get blown up. If we want more velocity, more power than your cartridge possesses simply go up a cartridge. An expert reloader told me that years ago, and that is what I do. I have a 7x57 Mauser, .243 Win, 22-250, 65CM, .308, and if I want to shoot laser beams, I have a 28 Nosler. I like the little to no recoil rounds, and I have a suppressor for the 28, so, it's no problem either. Keep each cartridge within its parameters, good advice from a very smart man, and I ain't talking about me lol.

 

[Jim’s Hunt]

Get a Redding,Wilson or Forster Full length neck bushing die. Best of both worlds

 

[6mm06guy]

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

I believe this is the collet die most people including myself, there's also alot of information on reloading the 300 Winchester mag on this website.

If you get one be sure to read the directions, because when it says not to use anything besides imperial sizing wax it means it..

 

[Xescane]

You can go as detailed as you want in reloading. I just finished up a 300WM (Factory Savage 10T-SR) and it shoots 5 into 1's and low 2's. I just flat don't do detail as if I am world record setting and days of case prep and loading 20 rounds. Some do I just don't see the need. Killed my buck this year one poke...480-500yds as last range I had was 485 and he moved around a little. Hit about 3" left of exact hold location. That rifle shoots 6's to high 7's.

I just finished up a 300WM (Factory Savage 10T-SR) and it shoots 5 into 1's and low 2's.

1. Loaded them with the same RCBS 300WM dies I purchased in the early 90's. Have 3 fires on some of the brass and still shoots just as good. I bump the shoulders 2K.....that is it!!!
2. Not in my world
3. I have a basic annealer.....and don't anneal every time. If I do anneal it may be 5 firings or 1 because when I think one batch needs it I anneal all the empty fired brass I have.
4. What?
5, Neck, shoulder, some body.

Ignorance is fixable and you are working on it.

You're definitely not getting all you can out of that gun. I have the same weapon and I'm shooting .25" and 100 yards and easily smacking 12" steel at 1,000. I'm doing the same thing with bumping the shoulders back and putting .02 tension on the neck. I've never annealed a single piece of my brass and I get three or four fireings out of them before they crack depending on the manufacturer. Other than that it's all about the bullet and the powder for that gun. It's a finicky one.

 

[Lee Goodwin]

I have reloaded a bunch, but, no expert...
All I can think to add here is:
300 WM, magnificent cartridge that it is, has a short neck. So short that it has caused me issues, in my naivete I set the shoulder back a touch too far...loaded 190s up kinda hot and some of the cases, after firing, showed way too much blow back...down the neck, over the shoulder and half way down the case and made the case look like I was trying to make a water trough for mice.
So, shoulder set back is very important.
Keeping my face intact comes in a close second.
Load on!!!
Lee