Correct way to 'bump' shoulder

WhelanLad

WhelanLad

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hey guys,
since this Kimber I started Neck sizing only when I reload cartridges for the 7mm08.

that's all going great with a few reloads in an chambering is fine, the odd one is a tad sticky to close bolt however im guessing after these firings it may be time to Full Length Size the cases just to tidy them up??.....


So ive borrowed my Cousins FLS set, but they arnt adjusted at all and I'd like to hear how I set it up to only just size my Case as to not stretch them on the next firing.

im sure someone will know what im saying and may be able to give me a decent run down on adjuisting the Die to suit?




is it a matter of starting well off, an slightly turning the die in, re checking and if needed screw in a little more?

thanks a lot CGN gurus! you're all legends, full of info

WL
 
WhelanLad,

What I've found the best thing to do with normal FL die setup is just as the manufacturer recommends with a hard seat between die and shellholder (sorry, the terminology section of my brain is still sleepy). Once you've achieved this, use these to get to minimum bump for your Kimber:
http://www.redding-reloading.com/online-catalog/35-competition-shellholder-sets

Or one of these sets: http://www.sinclairintl.com/reloading-equipment/reloading-dies/replacement-parts-upgrades/skip-s-die-shim-kit-7-8-14--prod33197.aspx

If I don't have one of these with an insert for a particular case: http://www.sinclairintl.com/reloading-equipment/measuring-tools/bullet-comparators/lnl-comparator-body-w-14-inserts-prod36535.aspx, I just start with the largest offset competition shellholder (or .010 to .014 worth of shims) and progressively work back from there, paying attention to how the sized case chambers.

And sorry, I don't know why the links didn't copy as links, so I just coloured them to differentiate the links from the rest of the text:rolleyes:

Has anyone else noticed that the Sinclair site doesn't list the Sinclair comparators that are similar to the Hornady sets? Have they been discontinued?

Rooster
 
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I do the same thing for a 7-08 i have - its simple -

Take a fired case from your rifle
measure base to shoulder using proper comparator
lets say it measures 1.750"
Set FL die so it barely touches shell holder
then run case thru FL die and measure
if no change tighten die 1/4 turn
repeat
eventually you will see the case get sized/bumped to where you want it, 2 thou bump would then read 1.748" from the original 1.75"
Done

Its simple - don't overthink it!
 
I set up my ordinary full length die so it is not contacting the shell holder with about a 1/8 inch gap. Run a case into the die to size it and then test it to see if it chambers in the rifle you want to use. It likely won't because the squeezing of the case has lengthened it a bit, but the shoulder was not pushed back by the shoulder of the die due to the gap you left.

Turn the die down a wee bit and resize another case. Test it in the rifle. If it still doesn't fit, repeat the process until the resized case allows the bolt to close easily. You now have the die set to full length resize the case but to push the shoulder back only as much as is needed to chamber in your rifle. Lock the die to that adjustment (you may well find it still has a small gap over the shell holder) and you're set to go. If you load for more than one rifle in that caliber, you will have to re-adjust it for the new chamber.
 
chrismc said:
I do the same thing for a 7-08 i have - its simple -


eventually you will see the case get sized/bumped to where you want it, 2 thou bump would then read 1.748" from the original 1.75"
Done

Its simple - don't overthink it!
Click to expand...

Not a math major but wouldn't that be a 3 thous. bump? LOL
 
WhelanLad said:
since this Kimber I started Neck sizing only when I reload cartridges for the 7mm08. that's all going great with a few reloads in an chambering is fine, the odd one is a tad sticky to close bolt however im guessing after these firings it may be time to Full Length Size the cases just to tidy them up??..... So ive borrowed my Cousins FLS set, but they arnt adjusted at all and I'd like to hear how I set it up to only just size my Case as to not stretch them on the next firing. im sure someone will know what im saying and may be able to give me a decent run down on adjuisting the Die to suit? is it a matter of starting well off, an slightly turning the die in, re checking and if needed screw in a little more?
Click to expand...

You have been given a few different ways to get the job done. Getting the measurement is the more difficult part. Hornady makes a tool to measure from the base to the shoulder. They sell a complete kit, or you can buy a body and the bushing for your 308. Have a look at the X-Reload site. As others and yourself have suggested, you measure what you have, and start long, and then keep screwing the die down until you get your 0.001 to 0.002" shoulder bump. Dies pretty much all use 7/8"x14 threads per inch. That works out to 0.071" per turn. 0.002" requires about a 10 degree turn of the die. On the circumference it will move about 2 mm. So when you start to get close, move in very small amounts.

If you get a FL die of your own, consider that you can do a partial resize of the neck, which kind of replaces the need for you neck only die. The advantage of doing a partial neck resize is that the case in the un-resized part will fit tighter and potentially improve accuracy. You can do that with your neck die too of course.

Hope that helps some,
 
If you use the same shellholder ,once you have your die set by going down little by little you can use a feeler gauge inbetween die and shell holder to record and have a repeatable die set for each caliber . My old way . Now I have a Forster datum dial set and it's really nice for this as well as bullet settings off ogive and other things . But the feeler gauges work fine UNTILL you get to spending the bucks on nicer tools
 
I use Redding competition shell holders as well.
If you are only loading 1 Cartridge that use a spasific holder they are pricy.

For those that I don't have these shell holders for I use Feeler gauges and set the die accordingly till I get the bump I am looking for. Starting at .010 and reducing till I get it right. Remember that to set up with a feeler gauge that the cam over of the ram will change the setting slightly. You only have to do this once then record what you find in your load book for that cartridge. Next time set the die with the right gauge and your good to go.

I also have made up comparators that allow me to shoulder length.

If you are using the size and chamber method always use a fired case for each test.
Also remember that as you reduce the distance between the shell holder and die you start pushing the shoulder forward before you achieve the correct setback.
I have one cartridges that at .008 shell holder from die will move the shoulder fwd about .003 when I measure it.
You may end up destroying a couple cases before you get it right, I did.

If you have any Questions send me a PM..

David

PS Keithjohn beet me to it.
 
I'm a big fan of Redding competition shellholders. Having said that, my experience with Kimbers is that I inevitably end up using the standard shell-holder screwed in hard and then some
in the end. Same goes for my carefully chambered custom barrels. Not
Every rifle needs a band-aid on the loading bench to
fix a gun makers sloppy machining.

When they wrote "Match grade chamber" in the ad copy,
That's what they were talking about.
 
We live in a plus and minus manufacturing world and dies and chambers vary in size, meaning diameter and length.

Without gauges you could raise the die off the shell holder and use feeler gauges to adjust the die downward until the case chambered without resistance.

The problem with the above method is it left a air gap between the die and shell holder and didn't take any slop and flex out of the press.

I'm still using the Rockchucker press I bought in 1973 and it is well used and has slop in the linkage.

And when the die makes hard contact with the shell holder you will have less variations in shoulder location after sizing.

I also use the Redding competition shell holders because the die still makes hard contact with the shell holder and removes any slop in the press.

Also once the die is setup you do not move the die to adjust the shoulder bump you just change the shell holders.

The deck height of the Redding competition shell holders where the case sits decreases .002 to .010. Meaning the case is not pushed as far into the die as it would with a normal shell holder.

Below is a illustration of what happens when full length resizing, if the die is adjusted too high you can make the case longer than its fired length. (blue dotted line)

If the die is setup per the dies instructions you can make the case much shorter than the chamber and cause case head separations.(green dotted line)

And when the die is a adjusted for a custom fit for your chamber the case shoulder will be .001 to .002 below the red dotted line.

shouldersetback_zpsjizx9lok.gif


Bottom line, your dies are adjustable up and down and can be adjusted for your case to be a custom fit in your rifle.

The dies directions are written to insure the cartridge is short enough to fit any chamber and many times this is much shorter than your chamber.

The best example of this is the British .303 Enfield chamber and American SAAMI full length dies that greatly over resize the cases.

I use the Hornady cartridge case headspace gauge with a low cost digital vernier caliper for my chronologically gifted eyesight. (subliminal suggestion for old folks)

You measure the fired length of the case and then adjust the die for the proper shoulder bump.

Many fired cases will not fit and drop into Wilson type case gauges and you get far more accurate readings with the Hornady gauge.
 
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With bolt actions .001 to .002 shoulder bump is recommended and for semi-autos .003 to .006 shoulder bump.

With my AR15s I use the Redding +.004 competition shell holder and get .003 shoulder bump.

With the standard RCBS shell holder and making hard contact with the shell holder the shoulder would be pushed back .007

I also have a Lee .223 full length die that will push the shoulder .009 if setup per the dies directions. And this die reduces the case diameter "more" than a small base die does.

Dies do vary in size and your the one that screws it into the press and locks it down. And sometimes you have to lap the top of the shell holder to get enough shoulder bump.

You have to play with the "plus and minus" to get a proper fit of the case in your chamber. (even if you have to take off your shoes) :evil:
 
Hey Whelan,

Here it’s the redding body die to bump the shoulders for two Savage bolt 7-08’s. One has a smaller chamber than the other by .002. The redding competition set as stated by the experienced here would be the way to go. Our inventory of rifles is small compared to many so the plan here is to lap down another lee shell holder (over a piece of glass) to provide the .002 difference instead of purchasing the whole redding set.


rral22 said:
... because the squeezing of the case has lengthened it a bit, but the shoulder was not pushed back by the shoulder of the die due to the gap you left. ....If you load for more than one rifle in that caliber, you will have to re-adjust it for the new chamber.
Click to expand...

Just to add to the above by rral … there was a point at which nothing happened and with small adjustment of the die, the shoulder bump occurred with a coinciding feel/resistance at the end of the stroke of the press. It was explained as the case lengthening first and then the shoulder press. For the equipment/brass/hardness levels of where we’re at, it’s either no bump or .002+ setback. Cant provide adjustment for in-between. (Thanks Dogleg for working me through that)

I have the hornady comparator system here to measure but Mystic’s trick of using masking tape (.004 thk) as a sort of “go” “no go” audit of the bumping process is what makes the most sense for me. Adjust body die so that cartridge will just fit the chamber, then add masking tape to the base of the cartridge, reinsert…bolt definitely doesn’t close. Adjust die, bump with different cartridge, tape and retest until there is slight/marginal resistance of bolt fully closing on taped cartridge. This indicates .004 or slightly less space. For me to follow what appears to be the concensus of .002 shoulder setback for hunting rounds, the process is set to have the bolt partially close with good/significant resistance preventing full closure. ( yes…I did need to measure with comparator to satisfy the other part of me. :rolleyes:) Jerry may add or subtract to what’s stated here.

For what its worth…I am a sophomore reloader bitten hard by the reloading bug. Results at the range have been better than imagined.

Good luck and regards
:cheers:
Ronr
 
Rightio lots of reading here Thanks.

I rekon I was Partial full length sizing my old .270, it had a large chamber.. a bit out of shape too I think. so I needed to bump in the bottom of the case an also the neck but until about 1mm from the shoulder. once I did this I was getting much longer case life.

ill have a look at this all tonight when I finish work!

much appreciated
 
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