Ok. I’m dealing with once fired , hopefully fully fire formed, brass unique to my rifle. I use my hornady comparator and note that the shoulder area has grown longer than unfixed brass. I realize that If the fired brass has fully expanded, that it should be reduced @. 002 at the shoulder. I do this with a neck resizer or my full length resizer, which I understand is the preferred method by many. I have also determined the overall length of the loaded cartridge by using the hornady oal length gauge with the modified case, which is obviously unfired. I want the bullet olive seated close to the rifling. What steps do I take to do this ? I am a veteran pistol caliber reloading who is teaching my son in law the manly art! He and I are both interested in learning precision rifle reloading. I have numerous manuals, but somehow am still confused on these steps. Any help / advice is greatly appreciated!
I am very confused on reloading fire formed brass steps.
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Chuck R.
Member
Normally, once fired isn't all the way formed to the chamber.. yet.
My preferred method is to disassemble my bolt and go for a fit that lets the bolt close almost all the way, then finally close with a small amount of pressure.
So IF that's happening with once fired brass (or sometimes the bolt just drops closing), I basically neck size using a properly set up FL sizing die (shims).. cause the brass isn't fully expanded to my chamber yet.
My secondary method is the Hornady Headspace Comparator and take .001-.002 off a 10rd average measurement of fired brass.
To get my "desired" bump, I use either FL or FL bushing dies set to FL size, BUT utilizing die shims to achieve the amount of offset required to get my "bump".. I set the dies up for FL sizing, then place a couple shims usually 0.018 total. Then by trial and error I reduce the shims until I get my .001-.002" bump. Once set, I record the number of shims used by rifle. It lest me load multiple rifles in the same caliber without adjusting dies.
Don't be surprised that once fired or even a couple times fired brass easily fits in the chamber. IF that's the case, then I just adjust my FL die (using shims) to basically just neck size, until a bump is needed.
Belted magnums add another aspect as a lot of dies don't size the area above the belt. This area can "swell" and cause difficulty chambering, especially when you're using once fired from a different chamber. Trying to FL size these to fix the 'swell" will often push your should back too much and limit your case life. For those I use a collet dies:
Bullet seating, I also use a comparator, 1st to figure max OAL with a bullet in the lands. Sometimes this doesn't make a bit of difference because you'll find you can't get to the lands due to mag length constraints.
Then my next step is to do some research, manufacturers sometimes have recommended amount of "jump" that their bullets like. Other times guys will have reported on various forums what works. I no longer just set my bullets for 0.0XX from the lands without researching 1st. IF I can't find anything, I go off the SAAMI specs as a start point.
My preferred method is to disassemble my bolt and go for a fit that lets the bolt close almost all the way, then finally close with a small amount of pressure.
So IF that's happening with once fired brass (or sometimes the bolt just drops closing), I basically neck size using a properly set up FL sizing die (shims).. cause the brass isn't fully expanded to my chamber yet.
My secondary method is the Hornady Headspace Comparator and take .001-.002 off a 10rd average measurement of fired brass.
To get my "desired" bump, I use either FL or FL bushing dies set to FL size, BUT utilizing die shims to achieve the amount of offset required to get my "bump".. I set the dies up for FL sizing, then place a couple shims usually 0.018 total. Then by trial and error I reduce the shims until I get my .001-.002" bump. Once set, I record the number of shims used by rifle. It lest me load multiple rifles in the same caliber without adjusting dies.
Don't be surprised that once fired or even a couple times fired brass easily fits in the chamber. IF that's the case, then I just adjust my FL die (using shims) to basically just neck size, until a bump is needed.
Belted magnums add another aspect as a lot of dies don't size the area above the belt. This area can "swell" and cause difficulty chambering, especially when you're using once fired from a different chamber. Trying to FL size these to fix the 'swell" will often push your should back too much and limit your case life. For those I use a collet dies:
Bullet seating, I also use a comparator, 1st to figure max OAL with a bullet in the lands. Sometimes this doesn't make a bit of difference because you'll find you can't get to the lands due to mag length constraints.
Then my next step is to do some research, manufacturers sometimes have recommended amount of "jump" that their bullets like. Other times guys will have reported on various forums what works. I no longer just set my bullets for 0.0XX from the lands without researching 1st. IF I can't find anything, I go off the SAAMI specs as a start point.
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jmorris
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You don’t really need measuring tools to set your dies. The rifle will tell you when there is or is not clearance in the chamber. If the ammunition is to be used in A given rifle, I often set them so the case is slightly compressed when the bolt is closed. Like this.
https://www.youtube.com/watch?v=2hWkcLPYOac
Using a marker to cover the projectile makes it easy to see where the rifling is making contact, if it is. Like the center bullet where you can see how deep that bullet was shoved into the short lead/throat of a Ruger barrel and even the one on the left, you can still see contact, despite being seated much deeper.
Tools are nice but if they are confusing you, might try just keeping it simple and easy to see and feel.
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jmorris
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Take a look in the load manual, they will tell you the maximum case length. If you have any that are over this dimension, you have reached the point, you need to trim them. They also give you a length to trim to.
I will point out that the method in the video above might not work if you need to feed the rounds into a number of different rifles; however, fired from the one you set the die up with, trimming won’t be something you spend much time doing.
The more clearance you have between the case and chamber, the more the case is going to grow the next time you size. The more you have to trim off, the shorter lifespan the case will have.
DM~
Member
tominboise
Member
After sizing, whether you neck size or full length size.
Also, for many years I determined the overall length of the cartridge to rifling, using a 1/4" oak dowel and a sharp pencil. The Nosler manuals have the process in them. Basically, close the bolt on an empty chamber, insert the dowel in the muzzle and bottom against the bolt face. Make a reference mark on the dowel at the muzzle end. Then, open the bolt, drop a bullet (not a loaded round - the bare bullet) in the chamber and hold against the throat, using a pencil or similar. Insert your dowel again and make a second reference mark at the muzzle. Measure between the marks for your overall cartridge "jam length". Back off your desired jump and go from there. I'd suggest 0.030" jump for hunting rifles with cup n core bullets, or 0.050" for mono bullets (all copper) as a starting point. As noted above, this may be too long for your magazine - you will have to check.
N555
Member
N555
Member
Yeah I have been reloading since 1999 and been reloading by feel, no Fancy measuring tools aside from a dial caliper and feeler gauges. I just started using a tube micrometer in like 2020 to aid in neck bushing selection.
Prior to the tube micrometer I was using a home made case mouth gauge to select the proper neck bushing, but that would always cause a least several cases to go in the do over pile and not be loaded till next time around.
AJC1
Member
Do not trim unless you are over maximum until you are positive the case is fully formed. If you are still filling out the shoulder your brass will shrink. If you have to trim, only trim to Sammi maximum until your case is fully formed. You should get a few firings before bump is required. I partial size until I get a crush fit and then use the fired case to determine hs. Then you can determine how much bump you want. One can cheat the system a little and partially seat a new primer and put it in the gun, using the bolt to seat the primer. Use your comparator to measure shoulder to base of primer.... it really helps to have a priming setup that doesn't use shell holders.
Blue68f100
Member
What die set do you have? The reason I ask is that some sets have a Body Die, which only size the body. Then you use a neck sizer to size the neck. Most std sizing dies will size the body and neck. Some use a mandrel die to set neck tension.
But in any case you will need to size the body to control the shoulder position. Like said it normally takes 3 firings to get if fully expanded to your chamber.
Welcome to THR
There are some real knowledgeable members on this site that will point you in the right direction.
Chuck R.
Member
Yes, but the standard dies will usually oversize the neck, it's normal and the expander button (deprimer rod as you called it) opens the neck back up to get the proper neck tension (for some of us, still too much tension).
A lot of us use bushing dies to only size the neck to achieve the tension we want and/or expander mandrels (which basically do what the expander button does, but more gently and on a upstroke) to save wear and tear on brass and get the best neck tension. I use a combination of FL sizing dies with neck bushings and FL sizing dies with the decapping rod/expander button removed, then use expanding mandrels.
The standard RCBS dies will make very good/excellent ammunition, especially when adjusted not to oversize your brass. Most everybody started this way and got their rifles to shoot well.
At this point I wouldn't over complicate things.. the instructions that came with the dies are pretty good, the only addition I'd make is to watch a video or two on how to properly adjust them to avoid oversizing your brass and creating excessive headspace.
AJC1
Member
I am not a bushing guy but a mandrel man. Yank that expander and run a mandrel and see if it helps.
N555
Member
We don't know what they're sizing.
Anything that head spaces off the rim or belt will probably push the shoulder way back further than it needs to be.
For 30-30 I run my rcbs FL sizer with a 15 thousands feeler gauge between the shell holder and die base.
I have also read that belted win mags are almost as bad. The dies push the shoulder back 10 to 15 thousands more than needed depending on the dies and gun.
I tried running my 6.5creedmoor dies with 3 thousands gap. Fired 3 new cases, sized at +0.003'' all fired once just fine and on the 2nd one might have closed with a tiny bit of resistance and definitely on 3rd loading the cases caused the bolt to close a bit harder than normal so I reset the die to kiss the shell holder and called it good.
barnfrog
Member
Thanks guys for all the info. I am
I am starting with 30.06 and 308 to begin with and hopefully eventually moving on to 303 Brit and 6.5 Jap.
As to OP's questions, I offer the perspective of a guy who started just a couple years back. For anything technical.....as reloading is......there are incremental learning steps along the way. Best not to worry about calculus or trigonometry until you got the basic math and algebra down pat. Point being, a lot of guys......me included......tend to get caught up in chasing things that are above our pay grade and really don't apply to us.
The basic set of instructions that come with each set of reloading dies is going to allow one to duplicate factory ammo. Now comes the good part. Everything you have asked about beyond the basic instructions involves an understanding of a much more complicated set of issues that has only a very modest benefit from all of them. By modest........that could mean reducing a 1 inch group at 100 yards obtained with very little effort to 1/2" or less that requires a whole lotta effort. It can be done, but at what cost? For example, just from a math perspective, that means all else being equal, you can reduce a 4 inch group at 400 yards to a 2 inch group at 400 yards. Is that important for your use? If so, fire away!
A bit more perspective. When setting up your sizing dies to resize your brass........consider that the difference between Go gauge .......the minimum chamber cut depth......and a NO GO gauge........for where the cut of chamber depth is stopped.....the maximum.......is only 4 thousands. Not all are that way......but many are. Than if you follow the basic die instructions.......you may only be setting shoulder bump back 4 thousands vs. the recommended 2 thousands..........so you are spending a lot of time and effort to fine tune that setting down to a range of only 2 thousands.......and that may not even matter much. And if the rifle and shooter are not up to the task, none of that will improve things no matter what you do.
Again......offered for perspective.
The basic set of instructions that come with each set of reloading dies is going to allow one to duplicate factory ammo. Now comes the good part. Everything you have asked about beyond the basic instructions involves an understanding of a much more complicated set of issues that has only a very modest benefit from all of them. By modest........that could mean reducing a 1 inch group at 100 yards obtained with very little effort to 1/2" or less that requires a whole lotta effort. It can be done, but at what cost? For example, just from a math perspective, that means all else being equal, you can reduce a 4 inch group at 400 yards to a 2 inch group at 400 yards. Is that important for your use? If so, fire away!
A bit more perspective. When setting up your sizing dies to resize your brass........consider that the difference between Go gauge .......the minimum chamber cut depth......and a NO GO gauge........for where the cut of chamber depth is stopped.....the maximum.......is only 4 thousands. Not all are that way......but many are. Than if you follow the basic die instructions.......you may only be setting shoulder bump back 4 thousands vs. the recommended 2 thousands..........so you are spending a lot of time and effort to fine tune that setting down to a range of only 2 thousands.......and that may not even matter much. And if the rifle and shooter are not up to the task, none of that will improve things no matter what you do.
Again......offered for perspective.
Chuck R.
Member
RGR all, but that's why I advised to adjust the dies.
The bottle necked cartridges headspace (for the most part) on the shoulder, to include the belted cartridges (once fired). Adjusting the die to not overly size is the same concept regardless of the case (for bottlenecks).
What you're doing with a feeler gauge is what I accomplish with die shims, just getting the correct offset between the die and shell holder to achieve the amount of sizing we want. Cool part about die shims or competition shell holders, is that they're quickly repeatable and eliminate having to adjust the die. Not an issue for the one rifle per die set guys, but when loading multiple rifles off the same set of dies, or doing experimentation, they really are the way to go.
Setting up dies to just factory FL (standard adjust to shell holder, than 1/4 turn more) isn't going to hurt anything except case life and depending on the chamber, might not hurt at all.
A pure neck sizing die, won't touch the shoulder. They've sort of gone out of fashion as the newer trend is to FL size case, just enough to fit.
About 98.999% of the guys buying comparator cases are getting the off-the shelf Hornady pre-made cases that are FL sixed brand new brass. They can't be fired, as they've been drilled and tapped for the comparator rod.
When you order a custom case, I've done several, I've sent Hornady 2-3 fireformed cases that were cleaned and they drilled and tapped the case head for me, minimal cost.
Blue68f100
Member
Like said the Std sizing die will size the body and neck. If you don't have a expander die leave the expander in the die. Make sure you use lube on the mouths about every 3-4 pieces. This lube will help to keep from stretching the necks when you back the sizing die out. The reason those wanting the best get a mandrel die. You may need to check the dia of the expander button if you are getting more than 0.003" interface fit. I like to know how much the sizing die is reducing the necks. Now all this is dependent on the wall thickness of the necks. It's not uncommon to have 0.002"+ differences between mfg.
Fore now forget about the LFCD. Unless your shooting a magazine fed gun, it's normally not needed. And then only if the the bullet has a cannelure. If not cannelure it will damage the bullet which impacts accuracy.
I don't really consider this fire forming, since we are not changing the case, we just want to case formed to the chamber. Once fired brass from your chamber has a little bit of wiggle room, it has to so it can extract freely, and that's a good thing. When we measure these cases as far as shoulder position goes we know they are a hair short of the chambers shoulder when the case is back against the breech face, When it's forward against the shoulder of the chamber we have the necessary head clearance to chamber freely. I want that, I don't want a crush fit for 99.99% of my shooting, I want free chambering cases that are not over sized and won't suffer from case head separation over the life of the case (8,9,10,11,12+) firings.
Fire a couple of cases with full loads three times in your chamber, measure shoulder position, set the sizer to move the shoulder back .001 to .002 and you'll get excellent accuracy, excellent case life, and never have chambering issues, assuming you get the sizer set correctly. Measure a few sample cases on each cycle of the cases to be sure we are staying within that max shoulder position (3 full power firings) and the .001/.002 bump back.
Another thing, not all of the cases, even the best cases from one lot, will all measure the same when getting shoulder position. My Lapua 6 Dasher cases will have a .001 spread after firing, and a .001 spread after sizing, so keep that in mind setting the sizer. If you go with .002/.003 you'll be fine if the cases are as fully formed to the chamber as it gets you'll still be fine.
If you fire the cases with only one full power load and go for .000/.001 bump back of the shoulder you'll be fine. Just make sure the sizer's shoulder is actually reaching the case's shoulder, if the sizer isn't down far enough you can get .000 and not be touching, which will bite you on future firings.
I set my .223 sizer to make cases fit the Sheridan case gauge and I still get 8 to 12 firings with no signs of case head separation, and that's more like .003+, so a screaming tight fit that may cause chambering issues at some point just really isn't that critical.
My Whidden 6 Dasher case gauge generally shows about +.001/.002 on fired cases and -.001/.002 on sized cases, and it shoots tiny little groups, with Lapua cases that have 7/8 firings on them, with zero signs of incipient case head separation.
I set my 300 BLK sizer to bump shoulders an average .003 on twice fired cases and they never have an issue. We just don't have to cut it real close, we just can't be sloppy. I later got a case gauge and found the cases fit the gauge this way.
A case gauge for setting sizers is really the easy button unless you have a bad chamber.
Fire a couple of cases with full loads three times in your chamber, measure shoulder position, set the sizer to move the shoulder back .001 to .002 and you'll get excellent accuracy, excellent case life, and never have chambering issues, assuming you get the sizer set correctly. Measure a few sample cases on each cycle of the cases to be sure we are staying within that max shoulder position (3 full power firings) and the .001/.002 bump back.
Another thing, not all of the cases, even the best cases from one lot, will all measure the same when getting shoulder position. My Lapua 6 Dasher cases will have a .001 spread after firing, and a .001 spread after sizing, so keep that in mind setting the sizer. If you go with .002/.003 you'll be fine if the cases are as fully formed to the chamber as it gets you'll still be fine.
If you fire the cases with only one full power load and go for .000/.001 bump back of the shoulder you'll be fine. Just make sure the sizer's shoulder is actually reaching the case's shoulder, if the sizer isn't down far enough you can get .000 and not be touching, which will bite you on future firings.
I set my .223 sizer to make cases fit the Sheridan case gauge and I still get 8 to 12 firings with no signs of case head separation, and that's more like .003+, so a screaming tight fit that may cause chambering issues at some point just really isn't that critical.
My Whidden 6 Dasher case gauge generally shows about +.001/.002 on fired cases and -.001/.002 on sized cases, and it shoots tiny little groups, with Lapua cases that have 7/8 firings on them, with zero signs of incipient case head separation.
I set my 300 BLK sizer to bump shoulders an average .003 on twice fired cases and they never have an issue. We just don't have to cut it real close, we just can't be sloppy. I later got a case gauge and found the cases fit the gauge this way.
A case gauge for setting sizers is really the easy button unless you have a bad chamber.
What a great idea ! I was wondering how to measure that setback, without buying more dies!
Another great idea! You guys are really helping me with great tips and tricks. These will be great to pass along to the son in law !
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