204 bump sizing help

A-dog

A-dog

New member
After strictly full length sizing for my 204, I have decided to try bump sizing to see if I can squeeze out a little more accuracy. The issue I am having is that I am not getting shoulder movement at all, even when the die is fully seated. Actually, the case seems to be expanding by a few thousands. I am using standard RCBS dies, and measuring with the hornady headspace gauge. I am trying to adjust the sizing die to only move the shoulder back .002". Has anyone else had this issue? I am beginning to think the die is just a bit long. Should I try a different die manufacturer? I think I remember reading online about some people having this same issue with RCBS full length sizing dies...
 
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Unless you are getting a snug bolt on closing, there is no need to bump anything. You will be creating more headspace, which is a bad thing. If you have the die screwed in until it touches the shell holder, plus another 1/4 turn down, you are getting a full length resize out of your die. Do they chamber easily, or do you get a hard closing bolt? By your post, I don't fully understand what you are trying to do. You screw the die OUT when just bumping shoulders. You state you have been full length resizing, so your shoulders are already being pushed back. A little more info would be nice.
 
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Nine horses, I understand full length sizing as re-forming brass back to original specifications. Since I am firing the brass from the same cooper 204, I am trying to get a bit more of a custom fit by simply bump sizing the fired brass. This way, the brass will be fireformed for that specific chamber. I have attempted to do this by simple backing the full length sizing die out of the press a bit so not as much of the brass will be run through the die in an attempt to preserve some of that custom fireformed shape. Does this make a bit more sense? I do not have a neck sizer, which is why I am going this route.

GLShooter, can you recommend the best way to grid down a shell holder? I am worried that I would grind it a bit unevenly, making lopsided brass.
 
A-Dog,,,Spend a couple of dollars and get a quality neck sizing die...The only reason to bump the shoulders on a .204 is if you are reloading for an AR,,The chamber in your bolt action will maintain the proper shoulder and normally the only change will be in neck length and that is dealt with by trimming...

It doesn't hurt to plan to anneal your brass after about six loadings as a rule.,,Some require it more often and some less, depending on how hot you are loading...
 
He's not trying to neck size, he is trying to bump the should .002. And he his die won't do it. Bumping .002 is what I do on all my stuff including match rifes. I would say take .010 off shell holder as recommended to be able to bump the shoulder. Have you put marker on neck to see how far the die is goibg down out of curiosity.?
 
Originally Posted By: A-dogNine horses, I understand full length sizing as re-forming brass back to original specifications. Since I am firing the brass from the same cooper 204, I am trying to get a bit more of a custom fit by simply bump sizing the fired brass. This way, the brass will be fireformed for that specific chamber. I have attempted to do this by simple backing the full length sizing die out of the press a bit so not as much of the brass will be run through the die in an attempt to preserve some of that custom fireformed shape. Does this make a bit more sense? I do not have a neck sizer, which is why I am going this route.

GLShooter, can you recommend the best way to grid down a shell holder? I am worried that I would grind it a bit unevenly, making lopsided brass.

You can partially neck by backing a die out but that doesn't really touch the shoulder. It will size the forward part of the case somewhat that will help in cartridge seating.. If you get NO movement at all when you are at full die taking the top off the shell holder will give you more reach. It doesn't have to be perfect as if you go down 0.010 it isn't going to hit anyway.

Anytime you "bump" a shoulder with a F/L die it is sized all the way. The second you touch that shoulder you are at full case sizing. Your option is to buy a Forester bushing die and just use it as it will do both an d not touch the body.

On a bolt gun NS only is fine as long as they are not overly tight. At some point a F/L size will be in order.

Greg
 
Thank you everyone for the help. It sounds like I just need to order a neck sizing die to do this the right way. This now brings up a whole new issue. From the research I have been doing, neck sizing dies use various bushings that you can swap out to achieve the desired neck size, or tension. Am I correct on this so far? Also, I have read about people shaving the inside and outside of the case neck to achieve various case neck dimensions. All this stuff is a bit beyond my abilities at the time. Can I neck size without doing all this fancy case prep? I always tumble, trim (if required) chamfer, and de-burr my brass as part of my normal case prep routine. Should I give up on trying to gain accuracy by neck sizing and simply stick to full length sizing?
 
I use the chamber to set my resizing die. I use standard dies backed out of the cam over, full length, position. You will need to move the die in 1/64 turns to get it just right. I set them so that I get a ever so slight crush fit. I get 15+ loads on my brass, and have been doing it this way over 30 years.

I don't think you will gain any accuracy from a bushing die in a sporter weight 204. If you were shooting a bench rest rifle, you might see it.
 
Originally Posted By: A-dogThank you everyone for the help. It sounds like I just need to order a neck sizing die to do this the right way. This now brings up a whole new issue. From the research I have been doing, neck sizing dies use various bushings that you can swap out to achieve the desired neck size, or tension. Am I correct on this so far? Also, I have read about people shaving the inside and outside of the case neck to achieve various case neck dimensions. All this stuff is a bit beyond my abilities at the time. Can I neck size without doing all this fancy case prep? I always tumble, trim (if required) chamfer, and de-burr my brass as part of my normal case prep routine. Should I give up on trying to gain accuracy by neck sizing and simply stick to full length sizing?

Congratulations on going from the world of case filling up into world of true handloading. Inside/outside neck turning seek to make sure neck thickness is consistent and when sized down will give a consistent bullet neck tension as one side is not squeezed in more/less than the other and you get a better bullet release.

In the case of a standard neck chamber/factory/SAAMI'd rifle the turning may result in some slight improvement. It shines in tight necked chambers that you are literally fitting the necks too. These will have about 0.001 to 0.002 extra room in the neck for minimal expansion. A standard non-turned neck won’t even fit in the chamber on many of these.

Picking a bushing size is easy. Just load a bullet measure the neck and subtract 0.001 to 0.005 off that. The smaller the number you use the higher the tension. Point of no benefit is about 0.006 BTW. If you want to clean up the necks that is usually done by setting your turner up for a light cut. When run down to the shoulder it will show about 75% of the neck being turned with some low spots showing. That’s pretty mild. If you go full turn you decide on what thickness you want that will clean it ALL up. If you go that route you will need to adjust your bushing sizes as above.

Inside neck turning/reaming is not done much as it does allow for more issues in control IMHO. The necks have to be nice and even and here you are still dealing with some inconsistent thickness. The process is good for removing “donuts” but that’s a different issue for latter.

We neck size all the time without turning and by and large we do well down range with it. Many times you can prep brass until the cows come home but that won’t turn every barrel into BR quality sub-0.2 MOA groups. Be realistic of your gear and start slow. Easy fixes to make them shoot are deburr flash holes, weigh cases, use a light crimp that is not abused by the system as in more crimp on an AR and lighter on the bolt guns. I F/L and neck size all my AR’s stuff. I will N/S for my bolt guns having cleaned up the brass. I only neck turn when I have a very tight chamber, not unusual in the wildcats I play with or just want to play. Like all my gear I have power attachments to make it easier on my old arthritic hands and wrists. My Makita gets the call anytime I have to work on brass including trimming unless I use one or two of my dedicated power trimmers.

Greg
 
GLShooter, I would love to sit down and pick your brain about these more advanced reloading techniques for an evening! It sounds like you hold all the answers I have been trying to find. I understand that my rifle is not a benchrest rifle, but it still is an incredibly accurate rifle. You are right...I do want to go beyond the standard "fill up the case" reloading. I appreciate your help and suggestions.
 
Originally Posted By: A-dogGLShooter, I would love to sit down and pick your brain about these more advanced reloading techniques for an evening! It sounds like you hold all the answers I have been trying to find. I understand that my rifle is not a benchrest rifle, but it still is an incredibly accurate rifle. You are right...I do want to go beyond the standard "fill up the case" reloading. I appreciate your help and suggestions.

Thanks for the compliment but trust me there are a huge number of guys on here that are EXTREMELY knowledgeable. Part of it is I'll set at the keyboard more than most. The talent here in the reloading/shooting area is unbelievable. I think that this comes from the wealth of experience in various venues these guys here have.

I learn things all the time here and talk to a great number of shooters across the net. Many ideas are spot on, many are OK and some are, shall we say, a bit skewed. I take part and partial and assemble my thoughts on problems. I've been proven to be all wet on occasion but I'm still swinging.

Of course setting across a reloading bench is often the best way to learn and having an OPEN mind is the biggest factor of it. I don't bash much on gear or writers. If someone is just patently dangerous I'll speak up or if they are so diametrically 180 degrees from reality I'll speak up. Safety is the one thing I never let slide. This whole process is simple and the guys here lay it out on a daily basis. I try just to chip in a few words.

Once again thanks for the compliment. Now for a shameless plug. Hopefully in the next few months I'll have my reloading book finished. Some of the stuff I've written on reloading/shooting will be in print along with many tips and tricks. I want it to be different than your average book by being a bit more far ranging in areas discussed and being self produced I can discuss brands etc. and not feel obligated. Ritch has been a tremendous resource for me and Carl has been a behind the scenes motivator. I have about 100 pages so far and it is still growing.

Greg
 
Originally Posted By: A-dogAfter strictly full length sizing for my 204, I have decided to try bump sizing to see if I can squeeze out a little more accuracy. The issue I am having is that I am not getting shoulder movement at all, even when the die is fully seated. Actually, the case seems to be expanding by a few thousands. I am using standard RCBS dies, and measuring with the hornady headspace gauge. I am trying to adjust the sizing die to only move the shoulder back .002". Has anyone else had this issue? I am beginning to think the die is just a bit long. Should I try a different die manufacturer? I think I remember reading online about some people having this same issue with RCBS full length sizing dies...

Case will expand / grow before it bumps back to desired length.

This way is a little different but the best in my opinion.
 


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