Sizing Die Adjustment - Needed??

[Barrelnut]

I've been following this thread....

Anyway, I think the Hornady head space gauges will shed light on what it happening. These measurements are the only way to know what is happening.

IMO, the problem may well be that you have a tight or minimum spec chamber. NOT a loose chamber. The die may not be able to size the brass back down small enough so that it fits easily back in the tight chamber. This happens more often than you would think.

Question: What brand and model rifle is this?
Also, does a once fired piece of brass fired from this rifle fit back in this rifle easily before it is resized with the die? Does it only have this problem after you have run it through the die?

 

[rcoody]

I've been following this thread....

Anyway, I think the Hornady head space gauges will shed light on what it happening. These measurements are the only way to know what is happening.

IMO, the problem may well be that you have a tight or minimum spec chamber. NOT a loose chamber. The die may not be able to size the brass back down small enough so that it fits easily back in the tight chamber. This happens more often than you would think.

Question: What brand and model rifle is this?
Also, does a once fired piece of brass fired from this rifle fit back in this rifle easily before it is resized with the die? Does it only have this problem after you have run it through the die?

I go with this one

Will fired and unsized brass chamber easily? Could.be the base of.your.brass is not being resized enough. If fired brass chambers easily you have eliminated that one. If not measure the base of a case right above the belt that does chamber, your fired brass and a resized case and compare them. Small base dies might be needed.

The reason your neck sized brass wouldn't chamber is periodically with neck sized brass you have to run them through a full length die to bump the shoulder and resize the rest of the case.

When you measure the headspace of your fired brass with the Hornady headspace gauge you will resolve another problem. If you have.a short chamber you have several remedies. Grind the bottom of the die. Find a thinner shellholder. Get a finish reamer and lengthen the chamber.

Personally i doubt you have a short chamber. I suspicion the die will bump the shoulder back plenty. It is something in the setup that is wrong

 

[Bitis Arietans]

Rc / Bnut

I can't thank you enough for weighing in here...
So, now at the end of my 3rd day of frustration, I have tried something else...please take a look, see what you think.

I've used my Hornady OAL Guage, with Bullet Comparator (that's used for Seating Depths.
I used the 41 cal, which fits well in the center of the case "taper"... Shoulder

Measuring new brass, every case gave me a measurement of 2.121 (2.120 to 2.122)

Measuring the Sized brass I got 2.133 (with some variation) but in every case the measurement was always at least .010"...to .010 - .012" LARGER.

So...what does this mean?

I have not tried to see if fired brass will chamber, as I have none, so I'll have to try. If it chambers well, does that mean I shouldn't FL Size the fired brass?
All of the brass has been FL Sized.

The rifle is an older (1980's) S & W Model 1500...All of the sized brass chambers like "silk" in my Sako Finnlight.

 

[Bitis Arietans]

The measurement just above the belt,
on the new brass - .507"
on the sized brass - .510-.512"

But both chamber in the Sako...

only the new brass chambers without difficulty in the Smith and Wesson, I still must try the fired (un-sized brass) in the S and W

 

[Barrelnut]

Yea, thought this might be happening. If the die does not adjust down enough to push the shoulder back, then when you size the case the shoulder will GROW. This is because the die is compressing the sides of the case and that has to go somewhere, so it pushes the shoulder FORWARD.

You probably have a short chamber and the brass never grows enough to be set back by the die.

Usually a magnum chamber is quite long because it is headspaced off the belt and the first time you are firing the brass it is not reaching the end of the chamber. This is common on magnum cases that headspace off the belt. If it is a LONG chamber

I this case I think you NEED to NK. I would get a neck die and only NK the brass for about three firings. You will then find them somewhat difficult to insert by only NK. Then use the FL die to resize the brass back only 2 thousands. If that doesn't work then it is a short chamber for sure and you will need to get a lower shellholder

 

[Barrelnut]

"Measuring the Sized brass I got 2.133 (with some variation) but in every case the measurement was always at least .010"...to .010 - .012" LARGER."

That .010 is about the max number I have see on belted case chambers. Belted mags leave a lot of shoulder room in the chamber for easy loading in bad conditions like sand or dirt in the chamber with a rhino after you. LOL

Usually after a couple firings I will see the brass grow that long at the shoulder and just set it back 2 thousands from there....

 

[Bitis Arietans]

Bnut

Your 7 MM RM Sized Brass measures 2.133", base of the case to the centerline of the shoulder?

That seems to make sense...my Barnes Handbook specs the case at:
(if I'm saying this correctly)
Base to bottom of shoulder - 2.0401"
Bottom of shoulder to top (start of the neck) -2.2288"

How to set it back .002"?

As to the short vs. long chambers...I still need to digest the info that you have been providing. My head is still spinning! lol!

Now, What would you say if I said, yesterday I screwed the FL Sizing Die quite a bit, and forced the ram up, almost at the risk of breaking the press...and the cases chambered better...I didn't press it too much, but at this point would you say a shell holder modification could be the simplest solution?

Can I buy a "shallow" shell holder? Thinking out loud!

 

[Barrelnut]

Bnut

Your 7 MM RM Sized Brass measures 2.133", base of the case to the centerline of the shoulder?

That seems to make sense...my Barnes Handbook specs the case at:
(if I'm saying this correctly)
Base to bottom of shoulder - 2.0401"
Bottom of shoulder to top (start of the neck) -2.2288"

How to set it back .002"?

As to the short vs. long chambers...I still need to digest the info that you have been providing. My head is still spinning! lol!

Now, What would you say if I said, yesterday I screwed the FL Sizing Die quite a bit, and forced the ram up, almost at the risk of breaking the press...and the cases chambered better...I didn't press it too much, but at this point would you say a shell holder modification could be the simplest solution?

Can I buy a "shallow" shell holder? Thinking out loud!

I say that if you screwed the die down hard and things got better, the Redding Competition shell holders might help. Another option might be to have a machinist take a couple thousands off the bottom of the die itself.

Yes Redding makes them for the 7mm Mag. They are not cheap...
http://www.redding-reloading.com/online-catalog/35-competition-shellholder-sets

 

[bigedp51]

Lapping the shell holder is the simplest and cheapest method and if you screw up you just buy another shell holder and start over. I do my lapping on on a thick piece of glass the size of a sheet of fine wet and dry sandpaper, but anything flat and level will work. Keep rotating the shell holder as you lap in a figure eight motion and measure often to ensure it is even. I would take .002 off at a time until the bolt closes with little resistance.

If you get the Hornady cartridge case headspace gauge you can set the shell holder for .001 to .002 shoulder bump.

NOTE, Redding competition shell holders push the case into the die from .002 to .010 "LESS" than a standard shell holder. Meaning they will not fix your problem and make it worse, they are used with dies that push the shoulder back too far and sill have the press cam over.

 

[sedancowboy]

Everyone else has tried to solve your problem so let me try. The Redding shell holders mentioned above start at +.002-+.010 not negative so that would make his problem worse not better. A regular shell holder is .125 from base of shell to top of shell holder which touches the die. He needs to take away from that not add to. So I would place a fine sheet of sand paper on a flat surface and turn the shell holder upside down and sand off .002-.004 and try it I will bet that he will be able to get the case into the die far enough to set the shoulder back and fit his S&W rifle. Assuming you run it up touching the die after the press toggles over. It that works problem solved use that shell holder with that set of dies for that gun. If it don't then you have to buy a new shell holder about 6-7 bucks.

 

[sedancowboy]

Big Ed you must have posted while I was typing. Yes you have it exactly right and a better explanation than I.
Thank you
Henry

 

[Bitis Arietans]

Big Ed / S Cowboy

Sounds like such an easy fix!lightbulb,,, and I got that kind of money "to throw around" $6-$7 on another shell holder...after all of the frustration $60 or $70 bucks seems like a small price to pay

I'm on it! Ordering a shell holder, and Head Space Gage..in the AM

• Hornady Lock-N-Load Headspace Gauge 5 Bushing Set with Comparator
• RCBS Precision Mic 7mm Remington Magnum

Thanks much!! I will let u know for sure.

 

[philipbrousseau]

it could be possible that the expander ball is stretching the shoulder foreward if you are not lubing the inside of the necks.

 

[Bitis Arietans]

Spoke with 2 techs at RCBS...they said the problem of a tight chamber is a lot more common than you'd think.
They agreed that lapping the shell holder would solve such a problem...but also suggested a "Small Base Sizer Die"...which was mentioned in someone's reply.

Made some purchases from Midway...More to follow...Thanks again to all!