Shoulder bump problem? Not far enough?

BillyGoatGruff

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Feb 1, 2013
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120
Hey guy's,
I am having an issue with my dies not bumping my shoulder back far enough. I'm having trouble with finding brass that will actually chamber in a new 7mm rem mag.
I'm working with brass that has been 1-3 times fired from a previous 7mm I had. I have measured a new once fired brass in the new rifle with a Hornady head-space gauge and my chamber measures out at 2.119". I've measured some factory rounds and they measure out 2.110"-114". I have multiple kinds of brass. ( fed,win, hor) I have about a 100 feds and not a one will chamber after re-sizing. I have about 50 win's and 75 hornady's and only about 25-30 % of those will chamber after re-sizing.

Dilema? why will some of the brass chamber and most not? It seems that the die is not bumping the shoulder back far enough? All the brass that fits measures under the .119" and anything over .1195" will not chamber.
I have two dies and get the same results with both. A standard RCBS FL die and a RCBS FL bushing die. Both set up as far down on the press as possible without damaging the press or the die. (screwed down touching the press at TDC plus a 1/4 turn).
I'm getting very frustrated. It's very dificult to work up a load when I cant get any consistency in my brass. All the brass has been trimmed to length and I've tried setting the dies up diferent with no change.
I have a Larry Willis collet die and I don't believe that it is a base problem.

I need help and or suggestions please

Thanks, BGG
 
Given the rifle's headspace and chamber is to spec, you could try removing about .010" off the top surface of the shell holder making sure that the neck sizer has sufficient clearance to clear the shoulder. Not a problem with bushing dyes which can be backed off a bit, or the bushing removed.
 
Given the rifle's headspace and chamber is to spec, you could try removing about .010" off the top surface of the shell holder making sure that the neck sizer has sufficient clearance to clear the shoulder. Not a problem with bushing dyes which can be backed off a bit, or the bushing removed.


+ one .
I normally take a few thousandths off the dye to keep from changing the shell holder because I have other dies that work perfect with it. ether way will work.

Also don't mix your brass because different brass has different spring back (Some is softer and some is harder)and the dies need to be set up for each brand.

You can use the same dies but you may have to adjust them slightly to end up with the same results.

Good luck

J E CUSTOM
 
Or, maybe you're screwing the die down too far.
Try backing off the die a half turn & see if you find a better path
 
You have another option, get an extended shell holder from RCBS or Precision reloading in your caliber. The extended shellholder will clearance into the chamfer on the die base allowing for lots of bump or more than you'll ever need.

I myself jig all my FL resize dies upside down in a jig I made up that fits a R8 indexing fixture and I surface grind about 0.005 off the bottom of all my dies to allow for the bump, if I need it. Factory dies will all have at least a 1/16th inch 60 degree chamfer on the bottom for ease of entry of the to be sized brass so 5 thou or so is inconsequential far as sizing the case is concerned.

That way, you don't have to crank the die down on the standard shellholder and/or cam over the ram. I'm not comfortable with an interfernece fit anyway. I load lots of straight wall cases and those dies can't comtact the shellholder. If they do, the brittle carbide insert breaks.

I also use the headspace gage fron Hornady. Sound like a 0.001-0.0015 bump is all you need, attainable either will the extended shellholder and/or grinding the die base and you can grind the base on an abrasive belt if yoiu do it carefully and maintain squareness. Just be sure to measure the material removed from the base by measuring the overall length of the die as you grind the base away. A couple thou will do it. I do 5 thou as a standard so all dies are the same for my benefit.
 
You have another option, get an extended shell holder from RCBS or Precision reloading in your caliber. The extended shellholder will clearance into the chamfer on the die base allowing for lots of bump or more than you'll ever need.

I myself jig all my FL resize dies upside down in a jig I made up that fits a R8 indexing fixture and I surface grind about 0.005 off the bottom of all my dies to allow for the bump, if I need it. Factory dies will all have at least a 1/16th inch 60 degree chamfer on the bottom for ease of entry of the to be sized brass so 5 thou or so is inconsequential far as sizing the case is concerned.

That way, you don't have to crank the die down on the standard shellholder and/or cam over the ram. I'm not comfortable with an interfernece fit anyway. I load lots of straight wall cases and those dies can't comtact the shellholder. If they do, the brittle carbide insert breaks.

I also use the headspace gage fron Hornady. Sound like a 0.001-0.0015 bump is all you need, attainable either will the extended shellholder and/or grinding the die base and you can grind the base on an abrasive belt if yoiu do it carefully and maintain squareness. Just be sure to measure the material removed from the base by measuring the overall length of the die as you grind the base away. A couple thou will do it. I do 5 thou as a standard so all dies are the same for my benefit.


And if you have 3 different rifles for the same caliber while the grinding off matl from the die MAY suit one rifle perfectly...if COULD "ruin" cases for another rifle.

Hence the reason I wanted REMOVABLE shims that I can use part of the time and not use for other rifles rounds!
 
I use Redding body dies and a set of Redding stepped shell holders. Then set the die up to contact the shell holder for a firm cam over but not too much. In a few instances I have had to grind a small amount off the die body to get me in the middle of the set of shell holders and match up for a -.0015" to .002" shoulder set back off of fully fire-formed cases. This gives me easy repeatable set up and adjustment both ways. Using this method I run the cases through the body die each firing. If they need a set back they get it, if they don't they get none. I feel this keeps my cases in a consistent spec all the time.

So if I were to go to grinding I would be measuring what I took off very often and shoot for a head space of .0015" to .002" or a little more if desired.

Jeff
 
FYI, Rem 700
and the brass doesn't fit in a friends 7mm either.

Greyfox, J E Custom
I'm not sure I want to try taking .010" off the shell holder or the die for that matter. I don't have the tools necessary to do it right.

SidecarFlip
I don't believe that an extended shell holder would accomplish anything? If I'm not mistaken the case depth going into the die would be limited by the belt? 7mm being a belted magnum?

Sully2
Where do I find these shimms your talking about?

Derek M.
I'm all for getting a new die if I new for sure it would work?

Broz
What does a body die do that a FL die wont? Stepped shell holders??? Are these thinner/shorter? would that be the same idea as the shimms that Sully2 mentioned? Again, wont I be limited by the belt?

Thanks for the suggestions and help. As of now no change.
BGG
 
Broz
What does a body die do that a FL die wont? Stepped shell holders??? Are these thinner/shorter? would that be the same idea as the shimms that Sully2 mentioned? Again, wont I be limited by the belt?

Thanks for the suggestions and help. As of now no change.
BGG

The body die just allows me to work on the case and neck in different steps. I feel this keeps run out to a minimum. I prefer doing the sizing in two steps. So the redding body die will not offer you more sizing unless you have a die that has an issue. I have seen that before too.

Redding offers a set of stepped shell holders that have the floor in .002" steps in height. This allows control on how much you size the brass and how much you push the shoulder back by controlling the amount you push the brass into the die.

I size belted cases with this method all the time. One of my favorite long range rifles is a 300 win.

If you have access to a belt sander and a dial or digital calipers you would be surprised how easy taking a few thousands off the die really is. Just keep it level and measure often.

Jeff
 
Broz

I tried Sully2's idea of a shim. I took a case that was sized and measured .126"
I then slipped a .010"standard feeler blade gauge beneath the case and ran it through again.
Low and behold it worked! I got .116"! THANKS Sully2!
So I think these shell holders you describe will work. If I read this correct? they will step UP INTO the die in .002" increments from a standard shell holder?

Thanks guys for throwing ideas at me and helping me find a solution to the problem. This has been driving me crazy for two weeks now.

This might be slightly off topic.
I have all this brass. Federal was the worst followed by Hornady then Winchester
as far as finding cases that would fit. The cases that I had the best luck with was some nickel coated Winchester. What is the purpose of the nickel coating and is this type brass any good?

What are the general opinions on brass? What's best?

Thanks again, BGG
 
And if you have 3 different rifles for the same caliber while the grinding off matl from the die MAY suit one rifle perfectly...if COULD "ruin" cases for another rifle.

Hence the reason I wanted REMOVABLE shims that I can use part of the time and not use for other rifles rounds!

I have more than 3 in some caliber families (as you know). Just because I remove a portion of the base has no impact on how much the shoulder is bumped back, thats entirely dependent on what the base to shell holder distance is at the top of the ram stroke and nothing else. By grinding off 0.005, I'm not altering the internal physical dimensions of the die or impacting it in any way other than allowing more latitude in bumping a shoulder, if necessary.

If I'm loading for Tom's 308 Hart barreled rifle, I use a previously ignited case to determine proper headspace, FL resize one and check it in the firearm right then and there to insure the bolt closes properly. If I reload for my Savage, I do the same or for Linda's Sako or Rod's Remington, the procedure never changes. The length of stroke on the ram to the very top (and the coarse adjustment of the die body) does change.

No 2 production rifles headspace the same due to tooling inconsistencies among other factors, so, it becomes a matter of setting correct bump for each rifle. I don't mix (and neither does the group) loaded cartridges between like caliber firearms. If, someone in the group or myself buy new unfired factory rounds, once they get ignited, the empty brass is the segregated to that particular rifle/handgun and stays there until it becomes unsafe and then it gors to Omni-Source.
 
Broz
So I think these shell holders you describe will work. If I read this correct? they will step UP INTO the die in .002" increments from a standard shell holder?

Thanks again, BGG

Actually they limit the amount of case protrusion from a standard shell holder. So you would need to grind the die slightly. Then you would have adjustability as to how much you size. Most dies over size when it comes to shoulder set back and these holders allow you to control that. The good thing about them is once you find the proper step to get perfect head space you will be able to pull the die and replace it to your spec first time. Just note the step of the holder used, set up so the die contacts the holder with a cam over and each time you will size the same amount.

Jeff
 
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