Hello Fellas,

I would like to know how you bump back the shoulder on your cases.

My set up, which many of you have helped me in the past with, is a M70 in 7mm Rem Mag. I am loading for this 7mm only and I already have a bag of fire-formed brass for it, so I have been neck sizing only with a Redding Neck Die.

I am a bit confused as to when I should bump back the shoulder...I have cases that I have fired 5 times and they still chamber freely....when do you all bump back your shoulders?

I bought a Redding Body Die that I tried for the first time last night with one of my cases. It was hard as hell to push the case all the way into the die so I am sure that the die resized the case....doesn't that defeat the purpose of having once fired brass?

I worked the case into the die several times, checking headspace each time and nothing happened...headspace didn't change at all.

I would like to hear your opinions on what I am doing as I am confused.

I'll be annealing next so watch out!!

If you are only neck sizing and the case chambers freely then the shoulder probably hasn't moved far enough forward to need bumping.

When I used only a neck sizing die I would keep track of the number of reloads and if anyone case in the batch became harder to chamber I would bump them all. I'm surprised if you are using anything but mild loads that you are nothing getting a sign of a crush fit.

A body die is going to resize the case back to factory std. Yes it can defeat the purpose of fireformed cases.

For anything but a target rifle I now simply either use custom dies fitted for my chamber or use factory and take a tight case and set the sizing die just low enough to allow me to chamber my brass in my rifle with now sign of a crush.

Not sure what you are talking about as to your headspace not changing. What are you measuring? Since a 7mag is designed to headspace off the belt. To extend life most will allow the brass to grow so that it headspaces from the shoulder like a non belted case.

If I had new brass and a new rifle I would use FL dies. Take a fired case and set the die to just touch the neck shoulder junction (assuming that the case chambered freely afterwards. If not lower the die until it just would.

If I was using only a neck sizing die and cases chamber freely I would leave the shoulder alone until I felt it start to crush. I have broken cases into a target vs hunting breakdown for rifles I only have neck dies for.
I think I talked awhile but not sure if I helped you any.

I measure my sloulder length and have it recorded in all of my load data for each of my rifles using 1X fired shoulder data

I like to use .004/.005 bump

Most here don't and will say it's a waste of time.....

Funny thing though with me knowing what my shoulder datum length actually is....I can tell you if a round will chamber in my rifle without running it through the gun.

Let's go....

Thanks Guys!

Ramrod, lots of great info here.

When I measure "Headspace" I use a Hornady gadget that attaches to your caliper and measures from the Datum Line to the base. Isn't that called Headspace? When I said that the headspace isn't changing, I mean that my original reading isn't changing. In my case 2.124 remains constant even with the die screwed all the way down. I feel pressure on my press handle so why isn't it changing.

Am I missing something here?

Crush Fit. Even when empty, my M70's bolt needs a push to go fully forward and a firm push down to lower the bolt handle, so yes the case might have a crush fit but I can't feel it when chambering it. Hmmm

I think that I am missing something obvious?

BTW, where do you buy Custom Dies and what do they get the measurement from....a once fired case?

You guys are the best thanks!

The only time you need to size or "bump" is when the case won't chamber easily...except the neck...you need to size the neck just to get a grip.

You only need to size about 0.001" or less if you are bench resting or in competition to keep case life as long as possible. I don't get all anal now like I did way back when I was bench resting, but still pretty close.

Someone always says "only accurate rifles are interesting"...but "accuracy" is in the eye of the beholder...and getting an inaccurate rifle to shoot accurately AND precisely is more fun for me. Once I get a shooter into that "5 shots touching" zone it becomes predictable and predictable is boring to me...I need a challenge.

I turn ALL my case necks...ALL calibers...just to get the possibility of an even expansion and bullet release.

I weigh sort cases AND bullets and sort the bullets by ogive length.

I trim, uniform primer pockets and de-bur/uniform flash holes, and of course weigh each powder load and seat by the thousandth after I've measured the bullet to land length.

I re-measure that distance after a few hundred shots depending on the caliber and amount of use, or after targeting and seeing the "5 shots touching " go to "wherethehellarethey"

I also fit my dies to a fired case, sometimes buying more than one brand of dies to get the fit I want and use competition shell holders or order a shell holder from Redding for a specific shoulder setback.

It is a total waste of time in many peoples minds to go through this process, but my rifles are basically ALL one holers with specific loads while those nay sayers shoot patterns.

The rifles might all kill but I can pick out which flea on what tick to take out while many are lucky to hit their animal in the first place.

Everyone does what they think is best for them and that is all right as far as I'm concerned. Sometimes it's the journey that counts most...not the destination or the end.

And YEAH...once you establish the headspace for YOUR rifle and your reloaded ammo is working perfectly...FORGET ABOUT changing things and enjoy the ride...remember factories make "AVERAGE" things to fit a set of specifications that are supposed to fit everything else...you KNOW that ain't right.

Factory rifle chambers and factory ammo are made to fit EVERYTHING, which means some to the ammo/chambers fit tight and some are as loose as......

If you are lucky enough to have a factory rifle with a SAAMI minimum chamber you are lucky

Measure the base just above the belt, the shoulder dia, the length from the base to the shoulder, and the base to the neck junction, the neck dia of a fired round, and use a Hornady comparator to measure a point on the shoulder ...THEN size the case and do the same measurements...WRITE THEM DOWN...compare the measurements...

You want the sized vase base measurement to be 0.001" OR LESS smaller than the fired case, and the same with the rest of the measurements...the neck OD will be much more than that and the comparator measurement should be less also...but if it doesn't change that's even better.

Basically when you size the brass that you move has to go somewhere and it usually goes up to the end of the case, that's why you have to trim each firing and the more brass that is moved the more material you have to trim away.

Most of the stretching happens just above the solid section of the case no matter if it is belted or not. There is where it thins out and you get head separation over time.

IF your sizing die fits the fired case, which means it fits the chamber you get minimal brass movement in all directions and LONG case life.

I'm about worn out typing...

I have several rifles that are known "case stretchers" with dies that fit and size minimally...I loaded and fired ONE 444 Marlin case with a Hornady 300 gr XTP at a top load 40 times...until I jus got tired of doing it...the case was still going strong...I trimmed a total 0 ~0.0220" over the course of the firing...about 0.0005"/firing...the case sits on my desk along with all the other bits and pieces...NO ONE believes me when I tell this.

I've done the same with a 223,(twice to 50 shots and two cases) a 308(several times using WW, RP, Lapua and LC military brass all lasting 30 times or more) a 7mmMag and 300 WM(ave 20 firings each but I don't do over 10 as a matter of course) and a 375 H&H(12 but it stretched due to pressure alone. I LOVE that caliber/case but a sharper shoulder would be better.)

Anyway...if it ain't broke....do your best to minimize sizing, keep the pressures down and the cases will last a long time.

Maybe I am missing it in your reply but how are you bumping back the shoulder without resizing the body?

Also, did you establish your headspace by taking the average of 5 or so cases?

If you try to push back the shoulder alone the body will bulge out some at the corner of the shoulder interfering with chambering.
For many purposes a common FL die works fine.
A FL die with a bushing is better if you want to go that way.

I establish my headspace by finding cases that are too long for my chamber and then slowing bumping back until the bolt closes with slight drag.

quote:

Originally posted by Leopardtrack:
Maybe I am missing it in your reply but how are you bumping back the shoulder without resizing the body?

Also, did you establish your headspace by taking the average of 5 or so cases?

SR4759, that makes sense as the brass has to go somewhere.

So I guess that I have to use a FL Sizing Die?

So with all this said....what is the point then of being happy with having brass fire-formed to your chamber if you are going to FL size it back?

It doesn't make sense unless I am missing something.

quote:

what is the point then of being happy with having brass fire-formed to your chamber if you are going to FL size it back?

The FL die will full length resize when you have it set to bump the shell holder. The case is tapered. When you have it set to only bump the case you are doing very little if any resizing to the body.

As 4759 said the case that is tight is the one that tells you the distance between the bolt face and shoulder. If it isn't tight then the case is shorter. As we said take the case(s) that are tight set your die to allow them to just fit. If you use that setting then shorter cases are not bumped, ones that have grown to be tight will be bumped.

Running a fl die to the shell holder will normally over resize for your chamber.

I am now understanding what you are saying.

Even when empty, my M70's bolt does need a bit of a push to seat the bolt fully forward and some pressure is necessary to push the bolt handle down as well, so it is hard to tell if the cases are getting tight or if it's just the closing. BTW, my action has been blueprinted by Hill Country Rifles, so I'm sure that nothing is wrong with the tight bolt close.

So you guys do neck size only until the case gets tight correct?

quote:

my M70's bolt does need a bit of a push to seat the bolt fully forward and some pressure is necessary to push the bolt handle down as well

Bet you are feeling the compression of the firing pin spring as the sear is picking it up from the cocking piece.

As I said normally I use either a custom die cut for my brass and chamber or a fl die set to just eliminate any crush fit. The crush we are talking about should be noticeable. When I do use a neck sizing die unless the brass became hard to chamber I didn't worry about the shoulder.

If you are not yet having issues I would wait until I did.

If you are not yet having issues I would wait until I did.[/QUOTE]

Thanks Paul. The above says it all

In the mean time I am going to look into a custom die.

If your ammo chambers, even with a slight feel on closing the bolt, you do not have a problem. That means you have zero excess headspace; usually a good thing. When it is too hard to close the bolt on a piece of sized brass, then it is time to FL resize it, then start over with neck sizing. I do not know why you need a custom die unless you like to spend money for no gain.

quote:

In the mean time I am going to look into a custom die

I have to agree with dpcd as to the custom die set. I buy custom because the majority of what I shoot is a wildcat of my own design. Those dies are set up for my chamber to do a minimum resize for a nice close fit.

I assume you have a factory chamber neck sizing like you do and bumping the shoulder when it gets tight should be just fine. Should you decide you can't live without an expensive custom then only buy the sizer.

I do disagree with dpcd when your brass gets tight I feel you should do the minimum required resizing to allow a sooth chambering. For me a full resize simply works your brass more than needed.

I should have said it that way; do the min sizing required to make them chamber easily. However, That is usually a FL sizing as when you try to partially size in a Fl die, that makes the shoulder move forward and compounds your problem. I have found.

As long as it chambers without undue force on the bolt, then just keep on doing what you're doing.

Dies and chambers are sometimes incompatible. Your chamber may be a bit on the short side (or your die on the long side), which is why your base-shoulder measurement doesn't change even when you size the case with the shellholder bumping the die base. If you ever need to bump the shoulders back (which you may not), then instead of going to the expense of buying a new or custom FL die, simply face off (grind) some thickness off of the top face of the shellholder. This will allow the case to be inserted deeper into the FL die and will let the FL die "bump" the shoulder back.

Custom dies from Redding or RCBS using 3 of your factory ammo, fired brass. Email them for price.

quote:

Originally posted by 243winxb:
Custom dies from Redding or RCBS using 3 of your factory ammo, fired brass. Email them for price.

The classic solution in search of a problem.

If the neck sized case fits the chamber, why bother bumping the shoulder. it will only result in brass flowing forward from the web area.

In my experience what I used to think was shoulder moved forward for years turned out to be a case of neck thickening. Empty case feeds fine but loaded ammo is tight. Those cases needed outer neck turning.

JMTBW

quote:

Originally posted by Stonecreek:

quote:

Originally posted by 243winxb:
Custom dies from Redding or RCBS using 3 of your factory ammo, fired brass. Email them for price.

The classic solution in search of a problem.

I disagree with this statement completely. I use this product and it serves me well. After 5 or 6 reloading my brass was getting hard to extract due to swelling directly above the belt. This collet setup up sizes the brass right down to the belt and I can get 5 or 6 more reloads from the same brass.

After all the work I do to my brass I want all the use I can get!

Leopard track- I would give up the neck sizing and go to partial full length resizing.... none of that shoot a bunch then bump the shoulders then start all over. Accuracy is nothing but consistency and PFLS will give you the most consistency.


.

The collet die is a great tool. Your case will go out of spec just above the belt way before you will need to bump the shoulder. Your primer pockets will probably loosen up before you need to bump the shoulder.

Leopard,
I mostly use FL dies set to a light drag with a stripped bolt. You can feel a much lighter drag with the guts out of the bolt. Once the die is set for a particular rifle it is never changed again.
I use the FL dies because they are easy to find, inexpensive and work well. I buy a lot of once fired brass from indoor ranges that is basically as good as new brass except it has been expanded once. To make sure it always fits my rifle after resizing requires a FL die. I do not use a separate die setting for each new batch of brass. The FL die set to exactly zero or .001 clearance will always chamber, yet gives excellent case life and accuracy.

Fire formed brass will still be longer than unfired brass and will fit your chamber better even when FL sized to min clearance.

You may still like using a neck die especially a bushing or collet type because there is no case lube involved. I do this for a few rifles mostly to get rid of the use of the lube. However the specialty dies are not made for all cartridges and are an added cost.

As far as making sense goes- there are some things that are about half way between truth and fiction. The notion that neck dies are always markedly more accurate is not guaranteed. A well set up FL die can give superb accuracy. A neck die that squashes the neck down too much then expands it back with an expander ball may be worse than a FL die.

There is one other area for precision that can make a FL die not work the way you want it to.
FL sizing takes more force. The speed that you size the case and the amount of lube on the case can affect how much the shoulder is pushed back. This variation might only be .001 to .002 but it is still variation in head to datum length. When I am forming cases or FL sizing cases, - if a case is sized too fast or has too little lube the case may be left long and you can feel the bolt close with more drag. I eliminate this variation by sizing the case slowly and allowing the ram to dwell 3 or 4 seconds at full stroke. This allows the brass to flow and stabilize. Then I lower the ram a little and size again with the same slow ram speed and dwell. Based on the feeling of the cases using a stripped bolt the variation is less than .001- I think. The variation is certainly less than what my calipers can resolve. I could check it with a .0001 indicator or mike but fussing about less than .001 headspace variation is getting into the area of knowledge for the fun of it rather than anything practical.

quote:

Originally posted by Leopardtrack:
SR4759, that makes sense as the brass has to go somewhere.

So I guess that I have to use a FL Sizing Die?

So with all this said....what is the point then of being happy with having brass fire-formed to your chamber if you are going to FL size it back?

It doesn't make sense unless I am missing something.

I use these parts........for fired cases, and stripped bolt case fitting/forming, measuring the headspace. Puts a "number" to a given chamber. Very consistent.

The extra parts are case adapters.

Hope this helps.

Kevin

Fellas, thanks again for all the great advice!

I gave Redding a call the other day and they pretty much concurred that I should be doing a partial re-size with a Full Length Die.

I also "smoked" a few cases with a candle/soot and found some interesting results...again this is for my 7mm Rem Mag:

1) 2.124" No contact
2) 2.125" No Contact
3) 2.226 Contact-Soot rubbed off the shoulder

So taking the thickness of the soot into
consideration, I assume that my die setting/headspace is 2.125??

You lost me. Is that after you FL resized? Those entire distances are along the shoulder. With 2.226 being right at the shoulder neck intersect.

quote:

Originally posted by Pegleg:
The collet die is a great tool. Your case will go out of spec just above the belt way before you will need to bump the shoulder. Your primer pockets will probably loosen up before you need to bump the shoulder.

Precisely. Just as JTex mentions above.

The below is a great die to fix the case out of spec just above the belt.

quote:

Originally posted by 243winxb:
Custom dies from Redding or RCBS using 3 of your factory ammo, fired brass. Email them for price.

So long as your finished reloads are chambering without excessive bolt pressure, just keep on doing what you're doing. No need to set the shoulder back unless the shoulder is far enough forward to interfere with chambering.

If you EVER need a collet-type lower body sizing die in order for your loads to chamber (regardless of whether the case is rimless, rimmed, rebated, semi-rimmed, or belted) then your pressures are unsustainable. You'll be using Scotch tape to keep your primers in at that point.

quote:

Originally posted by ramrod340:
You lost me. Is that after you FL resized? Those entire distances are along the shoulder. With 2.226 being right at the shoulder neck intersect.

Sorry Paul...I read it over and what I posted above is a bit confusing.

The measurements I posted above are NOT after any sizing. The measurements are from my brass after being fired from my gun.

When I said that contact (smoke soot) was seen on the case at 2.126", I am referring to contact seen on the case where the shoulder starts to slope towards the neck from the wall of the case....shoulder??

I think there is the possibility that your contact occurs at 2.126. You will have some clearance at 2.125.
I would check several cases at 2.126 with the firing pin assy removed from your bolt. You will eventually find a dimension that there is slight bolt drag when closing. Slight meaning it will require the pressure of one finger to close the bolt.
When there is some clearance you can sometimes feel it using a feeler gauge between the front of the bolt handle root and the receiver.

quote:

Originally posted by Leopardtrack:
Fellas, thanks again for all the great advice!

I gave Redding a call the other day and they pretty much concurred that I should be doing a partial re-size with a Full Length Die.

I also "smoked" a few cases with a candle/soot and found some interesting results...again this is for my 7mm Rem Mag:

1) 2.124" No contact
2) 2.125" No Contact
3) 2.226 Contact-Soot rubbed off the shoulder

So taking the thickness of the soot into
consideration, I assume that my die setting/headspace is 2.125??

quote:

Originally posted by Stonecreek:
So long as your finished reloads are chambering without excessive bolt pressure, just keep on doing what you're doing. No need to set the shoulder back unless the shoulder is far enough forward to interfere with chambering.

If you EVER need a collet-type lower body sizing die in order for your loads to chamber (regardless of whether the case is rimless, rimmed, rebated, semi-rimmed, or belted) then your pressures are unsustainable. You'll be using Scotch tape to keep your primers in at that point.

I have a .458 WM that I shoot a pressure tested load in that gets enough bulge ~1/4" above the belt that my FL shaves the brass. I started using the BM die BEFORE FL resizing and it solves the problem. I have reloaded some of the same brass for this rifle with the same load 10 times...primers still tight. When starting with new brass...the bulge does not show up enough to shave with FL until about RL 4 to 5. It is a highly accurrate rifle too. One of the few rifles (even some meant to do) I can consistently produce and almost one hole group with at a 100.

quote:

I have a .458 WM that I shoot a pressure tested load in that gets enough bulge ~1/4" above the belt that my FL shaves the brass.

The fault is in your FL die, which is apparently both too small in diameter and too sharp at the mouth (base opening) for brass fired in your chamber. I will stipulate that using the collet die first in this instance will enable you to subsequently use an otherwise incompatible FL die successfully, but the better fix would be to simply get a properly-dimensioned and finished FL die.

You could just as easily have the same problem with a .30-06 -- it's not the belt that is the issue here although manufacturers are infamous for taking liberties with belted magnum chambers on the theory that "the belt will take care of the headspace, so let's make it plenty big so as not to have any tight-chambering ammunition". An added advantage to manufacturers using larger-than-necessary chambering reamers is that the reamers, which wear down a little with each chamber, will make more chambers before they are worn below minimums if you start them out above maximums. This manufacturing practice is what has mislead people into believing that there is something somehow problematic about belted cases. 'Taint the belt, it's the oversized chambers.

quote:

I think there is the possibility that your contact occurs at 2.126. You will have some clearance at 2.125. I would check several cases at 2.126 with the firing pin assy removed from your bolt. You will eventually find a dimension that there is slight bolt drag when closing. Slight meaning it will require the pressure of one finger to close the bolt.

I think 4759 hit it pretty well.

I tend to agree with Stonewall as to the collet die. I feel they tend to correct problems. Like he said a FL die or large chamber or small brass or combination.
My first home grown wildcat I kept getting a ring near the base on my fired cases. Measure the brass switched brands to one just a touch larger in dia at the head and the ring went away. Had the reamer honed just a touch and all future chambering had no ring with either brass.

quote:

Originally posted by Stonecreek:

quote:

I have a .458 WM that I shoot a pressure tested load in that gets enough bulge ~1/4" above the belt that my FL shaves the brass.

The fault is in your FL die, which is apparently both too small in diameter and too sharp at the mouth (base opening) for brass fired in your chamber. I will stipulate that using the collet die first in this instance will enable you to subsequently use an otherwise incompatible FL die successfully, but the better fix would be to simply get a properly-dimensioned and finished FL die.

You could just as easily have the same problem with a .30-06 -- it's not the belt that is the issue here although manufacturers are infamous for taking liberties with belted magnum chambers on the theory that "the belt will take care of the headspace, so let's make it plenty big so as not to have any tight-chambering ammunition". An added advantage to manufacturers using larger-than-necessary chambering reamers is that the reamers, which wear down a little with each chamber, will make more chambers before they are worn below minimums if you start them out above maximums. This manufacturing practice is what has mislead people into believing that there is something somehow problematic about belted cases. 'Taint the belt, it's the oversized chambers.

I did at first assume my problem was my die. It is a Lee die. Although it only starts occurring after 4-5 reloads all done with this die. So I know two other people who live near me and that have .458 WM's and I borrowed a die from each...one a RCBS and one a Redding. All 3 dies shaved a little brass on these 4th & 5th time cases all in the same place...about a 1/4 inch from belt. Graybird on here told me think about the collet die above and I got one and it solved the problem.

The rifle is a 1957 Winchester 70 Supergrade customized in the Winchester Custom Shop for the original owner prior to shipment...I am the second owner.

In regards to the chamber being sloppy...you may be correct. But don't you think it is curious that the brass only does this after 4-5 reloads??? Really, it puzzles me so I am curious as too why...not that it really matters that much...but I like academics.

Sorry for the "light" high jack Leopardtrack.

quote:

In regards to the chamber being sloppy...you may be correct. But don't you think it is curious that the brass only does this after 4-5 reloads??? Really, it puzzles me so I am curious as too why...not that it really matters that much...but I like academics.

Could it simply be that the chamber is a touch large or brass small or combination. After the 4-5 firings the brass gets work hardened and doesn't spring back as much leaving your die more to contact and try to compress back?

That could very well be it. I guess I would have cerosafe cast the chamber to know for sure. The collet die seems to solve the problem fine and why I have just stuck with it.

Here is what Larry Willis says about his belted magnum collet die.

Belted magnum cartridges have been around for over 50 years, and most shooters that reload them are familiar with the case bulge problem that occurs "just above" the belt. This usually happens after just 2 or 3 firings - wasting perfectly good cases. Many shooters have discovered this problem when they find their handloads begin to stick in their chamber, or when they no longer chamber at all.

Unlike non-belted cases, the belt prevents conventional full length dies from traveling far enough down the case. This limits the amount of resizing, and brass is plowed rearward. The brass builds up just above the belt at each reloading, and cases expand. Neck sizing dies don't bump the shoulder back or resize the tapered case wall. The best solution is to full length resize accurately, and use this collet die to reduce case width.

Our patented Belted Magnum Collet Resizing Die solves this problem and has other unique features. The top of this die is a case width gauge that shows when a little "extra" case resizing is required. This resizing die is used to eliminate the case bulge above the belt, after using your full length (or) neck sizing die. Our collet die ensures that your belted magnum ammo will always chamber properly and your cases are now able to last for up to 20 firings, even when using the hottest handloads. Our resizing die uses a collet that fits over the cartridge case, until it bottoms against the belt. The case is then pressed into the sizing die. The collet allows your case to go farther into the die where it only reduces the area "just above" the belt.

quote:

The collet die seems to solve the problem fine and why I have just stuck with it.

There you go. You have a problem for whatever reason. If this die cures the issue then for sure stick with it.