Cartridge gauge and reloads

[scott_r]

Hey guys, I recently got my hands on a case gauge for .223 and noticed after full length sizing some of my brass still does not drop in loose, some seem a bit larger right at the base. These ones sit a thumbnail higher then flush and can be pushed down to fit. Im wondering why some brass drop in fine and other dont, even though every thing is done the same? Does some brass just expand ever so slight after resizing?

 

[Potashminer]

I had read that many (most ?) full length sizing dies can not size the entire case head - might be what you are seeing??? If your case head is expanding beyond spec, then your loads are much to high - would be surprised if primer pockets still tight? I am very old-school - tight primer pockets to me are the sign I use whether pressure in load is okay or time to chuck the brass and back down a notch - most brass should be good for 4 or 5 loads with tight primer pockets. Can not anneal that end; some can resize by pushing through a larger carbide type pistol die of correct size, although I have never done that.

 

[Rod B]

A body die would resolve this situation.

 

[bigedp51]

double post

 

[bigedp51]

What brand of case gauge are you using, most case gauges have an inside diameter close to the maximum SAAMI diameter.

Below a Wilson, Dillon, and JP Enterprise .223 case gauges with the case placed in base first. And this shows that the JP Enterprise gauge is closer to the minimum case diameter.

If the case rim has a ding it can prevent the case from dropping all the way into the gauge. I keep a small fine file on my reloading bench to file down any dings.

If you are using range pickup brass fired in other rifles, the brass spring back after sizing can effect using a gauge.

A small base die or pausing at the top of the ram stroke for a few seconds will reduce brass spring back. Meaning if the case body is the problem try pausing at the top of the ram stroke before buying a small base die.

Chambers and dies vary in size and you might have a die on the plus side of manufacturing tolerances. For example I have a Lee .223 die that will reduce the case body diameter more than my RCBS small base die.

Another example with .308 case gauges below, in the Dillon gauge is a "FIRED" 7.62 Lake City case.

Below the same "FIRED" Lake City case in a JP Enterprise gauge showing its smaller case body diameter.

Does some brass just expand ever so slight after resizing?

"YES" the brass can spring back after sizing, and the harder the brass the more it will spring back. This is also why range pickup brass can give you problems, the case wants to spring back to its fired diameter. I buy bulk once fired Lake City 5.56 and 7.62 brass fired in a multitude of different chambers. And I size the cases the first time using a small base die and check the resized case in my JP Enterprise gauges. If the case fits in the JP Enterprise gauge it will chamber in any rifle.

And again most case gauges are on the max side of case body diameter and only check headspace length. So reverse the problem cases and put them in base first and see if they fit in your gauge, you might just have a ding on the case rim.

 

[scott_r]

bigedp51 , Thanks for the detailed post. Im using a Lyman gauge. I purchased some used brass, its the same same headstamp but its not new. I will also check the rims for any burs.

Cheers!!

 

[Potashminer]

Do not lose track that the goal is to fit properly into your chamber - the gauge is supposed to be a step along the way to that - fitting into the gauge is not the objective - fitting into your chamber is! The gauge and your chamber may or may not agree. You did not mention if you have a semi, bolt, pump or single shot rifle - very often recommended to re-size with small base dies for most everything except some bolt actions. I would think doubly so if you are starting with brass previously fired in another chamber.

 

[scott_r]

Do not lose track that the goal is to fit properly into your chamber - the gauge is supposed to be a step along the way to that - fitting into the gauge is not the objective - fitting into your chamber is! The gauge and your chamber may or may not agree. You did not mention if you have a semi, bolt, pump or single shot rifle - very often recommended to re-size with small base dies for most everything except some bolt actions. I would think doubly so if you are starting with brass previously fired in another chamber.

Good info, thanks. I think I may purchase some sb dies just to make sure I have no issues.

Cheers!!

 

[JEC]

I have reloaded many thousands of CF rounds in several different “custom” chambers cut with reamers that are typically a little tighter than normal specs ... and never required small base dies (bolt action). Some brass has been cycled 30+ times. Personally, I would hold off on purchasing small base dies unless needed. Over sizing towards the web will just result in greater radial clearance ... IMO less “slop” is better.