Will a 30-06 Case Gage Work for 270 Win?

[Syncrowave]

Hey, all,

I want to back out my FL sizing dies so that they just "bump" the shoulders on my 270 Win and 30-06 cases (I only have one rifle in each caliber) to get a better "fit" in each chamber, and to make the cases last longer before work-hardening and needing to anneal the necks and shoulders.

Planning to use the L.E. Wilson case gage for this. Like this one:

My question is, since the 30-06 and 270 are basically the same case, just necked down on the 270, and therefore should have the same distance between the base of the case and the datum on the shoulder, can I use the same Wilson Case Gage for both 30-06 and 270 Win?

Thanks in advance.

 

[watercam]

For the measurement you need, yes you can.

 

[dantiff2]

This won't work... As the body taper of the case gets squeezed in the die the shoulder (datum) actually gets pushed upwards toward the neck until the case is in the die all the way for the die to act on the shoulder and push it back down. Try for yourself. If you remove the primers of a few spent cases, get a good accurate base to datum measurement. Run them short in your die, say 3/4 of the neck then remeasure your datum to base measurement. I've tried this on several different calibers. You need a bushing bump die. It does not have the body taper included in the sizing of the brass.

Dan

 

[Patch700]

This won't work... As the body taper of the case gets squeezed in the die the shoulder (datum) actually gets pushed upwards toward the neck until the case is in the die all the way for the die to act on the shoulder and push it back down. Try for yourself. If you remove the primers of a few spent cases, get a good accurate base to datum measurement. Run them short in your die, say 3/4 of the neck then remeasure your datum to base measurement. I've tried this on several different calibers. You need a bushing bump die. It does not have the body taper included in the sizing of the brass.

Dan

That is not written in stone Dan... In some or most cases this may happen but the truth of the matter is that it all depends on the die you are using with that specific fired brass that came out of that specific chamber.

This gets back to the easy way out question of "Which is the best sizing die out there?" .. The short answer is the die that most closely matches your chamber and fired brass.. No matter who makes it , could be two dies from the same mfg but with different inner dimensions.

 

[dantiff2]

This won't work... As the body taper of the case gets squeezed in the die the shoulder (datum) actually gets pushed upwards toward the neck until the case is in the die all the way for the die to act on the shoulder and push it back down. Try for yourself. If you remove the primers of a few spent cases, get a good accurate base to datum measurement. Run them short in your die, say 3/4 of the neck then remeasure your datum to base measurement. I've tried this on several different calibers. You need a bushing bump die. It does not have the body taper included in the sizing of the brass.

Dan

That is not written in stone Dan... In some or most cases this may happen but the truth of the matter is that it all depends on the die you are using with that specific fired brass that came out of that specific chamber.

This gets back to the easy way out question of "Which is the best sizing die out there?" .. The short answer is the die that most closely matches your chamber and fired brass.. No matter who makes it , could be two dies from the same mfg but with different inner dimensions.

I think in this case we would be safe to say that it probably wont work. The OP is obviously trying to use a FL die as a bump and neck die without working the body. That tells me that we are not dealing with someone who has custom dies made to a reamer print, etc. This would only work if you had a custom die made to an extremely minimal sizing tolerance.

*edit* By the time a FL die touches the shoulder, it has worked the whole length/ body of the case. No other way around this...


Dan

 

[Syncrowave]

Thanks for the replies.

FWIW, I spoke to a tech at Sinclair / Brownell's who said I should be able to do both cartridges with the 30-06 Case Gage...fingers crossed...

I don't really care if the case body gets worked; what I'm trying to avoid is moving the shoulder back more than .002" or .003" from its fired dimension.

 

[Dusty Stevens]

Why dont you scrap that idea and use the gun to set it up? I can guarantee you 100% that there is tolerances involved that wont work in your favor. That gauge assures the case will fit every chamber it has nothing to do with how your chamber is headspaced. Back your die out then try to close your bolt screwing the die in til it fits and the handle hits on the way closed. Be sure to check multiple cases unless youve annealed em cause theyll all be different and if youre gonna shoot at something that bites check em 100% with another bump on the die

 

[fguffey]

*edit* By the time a FL die touches the shoulder, it has worked the whole length/ body of the case. No other way around this...

With my methods and techniques I do not find it is necessary to adjust the die down to the shell holder with the proverbial additional fraction of a turn after contact. Proverbial fraction of a turn: 1/4, 1/2, 3/4 etc. The die is referred to as being a full length sizing die. My full length sizing dies will return the case to minimum length/full length sized.

I have a 98 +/- a few months year old Eddystone M1917 that went through Utah for repairs, it has a long chamber. When the chamber length is measured from the shoulder to the bolt face all indications point to the chamber having an additional .016" added to the length of the chamber from the shoulder to the bolt face. My M1917 rifle is not rare and or unseal, the long chamber is common. When sizing cases for that chamber I form 280 Remington cases by adjusting the die off the shell holder with a .014" thick feeler gage. I also have a 30/06 case forming/trim die I use when forming fired cases.

The perception, the additional .016" adds to the case head protrusion and or unsupported case head, not so. The case head protrusions is less than the Mauser at .110" but the same as the 1903 Springfield.

The case gage by Wilson has a datum, thought no one would recognize it, it has a radius. I have always thought that feature was brilliant, Wilson has been making case gages for 60 + years, today everyone takes credit for the discovery of the datum and how to use it. The Wilson case gage is a datum based tool.

Thanks in advance.

A reloader with minimum shop skills can make datum based tools, for the 30/06, 270 Winchester and 25/06 Etc. the datum/hole must be .375 with a sharp edge and the ability to measure from the surface the hole is drilled through to the case head. All of the case gages for the cases that use the 30/06 case including the 8mm/06 use the same datum/./8 round hole.

difference between the 30/06 and 270 Winchester case gage? When measuring from the datum the case is measured from the datum to the case head 'AND' from the datum to the end of the neck. The 270 case has a longer neck than the 30/06. Meaning there is a .041" difference in case length between the 30/06 and the 270 Winchester.

Then there is the 280 Remington, the length of the case body from the 280 Remington and 30/06 is .051" when measured from the shoulder to the case head. the datum round hole diameter is the same. Meaning? when using the datum of the 30/06 when measuring the length of the case body for the 280 Remington keep up with the difference in length between the two cases.

F. Guffey

 

[fguffey]

Back to minimum shop skills: In the big inning Wilson furnished instructions with their case gages. They suggested their case gage be used with a pocket rule/straight edge. I have no problem finding a straight edge, instead of making a wild guestimate of the gap between the bottom of the case gage and case head I use the companion tool to the press, the feeler gage. The straight edge and feeler gage turn to Wilson case gage into a precision gage.

FWIW, I spoke to a tech at Sinclair / Brownell's who said I should be able to do both cartridges with the 30-06 Case Gage...fingers crossed...

If you are able to drill a 3/8' diameter hole that is perpendicular you can make datums.

F. Guffey

 

[Sheldon N]

Hornady uses the same dimension headspace comparator for both 30-06 and 270. Their inner diameter is 0.375" (3/8") for both calibers.

 

[Syncrowave]

Thanks, guys. I'll report back if the 06 gage doesn't work for me.

Edit: Now I think about it, I can just adjust the FL sizing die in little by little until the bolt will just close on the fired and re-sized case (they're bolt actions -- M70 and M98) ... and then add some fraction of a turn to the die (calculated to add maybe .003") ... and then I don't need the case gage. Right? Is that what you're saying, Dusty?

One other thing -- some of these cases I want to size to the chamber were never fired in that chamber ... I have some old LC Match cases and range pickups and 1X stuff I bought here.

 

[Brians356]

The simple answer to your simple question is "Yes". The SAAMI specs for body and shoulder are identical for the two cases. The case "headspace" max dimension, base to the .375" datum on the shoulder, are both 2.0562", and the shoulder angle 17.5 deg.

However, the 270 Win gauge should have a smaller hole for the neck, so it' possible you could have a case with a "false shoulder" (e.g. a 30-06 case only partially necked down to 270) which would not enter all the way home in a "270" gauge. In that sense, as pure case gauges they are not strictly interchangeable both ways. Happily, you have the one with the larger neck hole. ;-)

 

[Syncrowave]

Thanks. Yeah, I was going to use the 06 gage for 270 cases, not vice-versa.

 

[Dusty Stevens]

Its still not a way to set up headspace in your chamber to .001- you can only do that in your gun

 

[Brians356]

Thanks. Yeah, I was going to use the 06 gage for 270 cases, not vice-versa.

Note I added "... not strictly interchangeable both ways. Happily, you have the one with the larger neck hole. ;-)" to my earlier post.

 

['Freak]

Assuming the case doesn’t need trimming so that the case mouth won’t be poked out the neck end of the Wilson case gauge, you can use the Wilson gauge body to get a case head to shoulder datum reference measurement the same as if you were using the proper Hornady or Sinclair insert in their gauge body. Just gotta be sure that the caliber registers on the case head, not on the Wilson’s high step, and get your reference number by measuring from the case head to the neck end of the Wilson gauge body.

 

[Syncrowave]

Its still not a way to set up headspace in your chamber to .001- you can only do that in your gun

Thanks again. Yes, I've tried that with an AR and RCBS 223 Precision Gage or whatever it's called and I've found that even with the die set in one position, case headspace varies coming out by up to .003" or so. I guess this is due to how work-hardened / springy the case necks are, which differs from case to case, even within a batch of brass from the same mfgr and number of firings. So if I can get it +/- .002" I call it good. If I need another .001" or so, I just put a little more die wax on the shoulder and cycle the press again. (Those are only for a Service Rifle.)


If I can get these 06 and 270 case shoulders +/- .002" or .003" for my hunting rifles, I'll be more than happy.

 

[fguffey]

Its still not a way to set up headspace in your chamber to .001- you can only do that in your gun

The case does not have head space. L.E. Wilson named their gage 'case gage', they did not label it a head space gage. It is not possible to set the head space in the chamber, it is possible to 'set' the clearance. I offset the length of the chamber with the length of the case.

F. Guffey