FL size below .200” line?

[SDHNTR]

Here is my case I ran through that die. Ignore the jacked up neck. I happened to get an older one before they started opening the neck larger to accommodate other calibers. They fixed it for me.

View attachment 704815

OR you can use it before the FL die if you're not using a mandrel. Also, if you use it every time from the start, it will keep that area in check and won't size it as much so you won't see any change in base to shoulder.

This was my plan. Seems I would want to do it before (with no mandrel) in case it lengthened the headspace, and then FL size back to my preferred .002 bump.

 

[Ucsdryder]

This was my plan. Seems I would want to do it before (with no mandrel) in case it lengthened the headspace, and then FL size back to my preferred .002 bump.

Very curious how it works. If you do it, measure your brass before and after at the .200 line and report back on here please!

I always assumed there was a reason that dies always sized down to the web, not past it. Why wouldn’t they make the dies 1/4” longer and size to the ejector groove? Wouldn’t this solve all clicker issues?

 

[crich]

Just so I'm clear.... FL size then run the mandrel die? Just started out with load dev for my 300prc and I'm always looking for ways to make my reloads more consistent. I haven't branched out to mandrel dies yet.

Yeah the idea is that a bushing die will size the neck slightly smaller than you want. Then the mandrel will open it back up where you want it providing the most consistent bearing surface on the projectile each time.

The Cortina mandrel die sizing the base will probably lengthen your brass like SDHNTR was referencing. If you wanted to use a mandrel that doesnt do that the 21st century dies sre good.

This was my plan. Seems I would want to do it before (with no mandrel) in case it lengthened the headspace, and then FL size back to my preferred .002 bump.

Not a bad idea since in theory it will probably lengthenth case and youd have to account for that. I'd run a piece of brass through both ways switching up the order to see what It does. The Cortina and SAC sizing dies do the same thing but buying the mandrel die with no mandrel is definitely the cost effective way to do it.

 

[wapitibob]

This was my plan. Seems I would want to do it before (with no mandrel) in case it lengthened the headspace, and then FL size back to my preferred .002 bump.

I've measured several thou increase in length after fl sizing so I bump last.

 

[crich]

Very curious how it works. If you do it, measure your brass before and after at the .200 line and report back on here please!

I always assumed there was a reason that dies always sized down to the web, not past it. Why wouldn’t they make the dies 1/4” longer and size to the ejector groove? Wouldn’t this solve all clicker issues?

Getting pretty close to trying to squeeze a solid piece of brass at that point.

 

[SloppyJ]

Yeah the idea is that a bushing die will size the neck slightly smaller than you want. Then the mandrel will open it back up where you want it providing the most consistent bearing surface on the projectile each time.

The Cortina mandrel die sizing the base will probably lengthen your brass like SDHNTR was referencing. If you wanted to use a mandrel that doesnt do that the 21st century dies sre good.

Not a bad idea since in theory it will probably lengthenth case and youd have to account for that. I'd run a piece of brass through both ways switching up the order to see what It does. The Cortina and SAC sizing dies do the same thing but buying the mandrel die with no mandrel is definitely the cost effective way to do it.

My thought was with a FL sizing die with a mandrel not a bushing. I think SD was talking about a FL die with a bushing.

I'm trying to keep it simple with the normal FL sizing die for all of my cartridges. I don't own any bushing dies but don't have a problem making the switch if they're going to provide better results. I just want to explore all avenues with what I have first.

 

[Ucsdryder]

Getting pretty close to trying to squeeze a solid piece of brass at that point.

But isn’t that exactly what this die is doing? Why does it work for the micron die but not a Hornady custom or the like?

 

[Lawnboi]

But isn’t that exactly what this die is doing? Why does it work for the micron die but not a Hornady custom or the like?View attachment 704884

Some premium dies like your micron, and SAC are designed to size more of the case to combat the problems that can occur

Reloading tech is coming around just as rifles/equipment are. Most guys years ago didn’t load a piece of brass 10-20 times, same can be said for the number of people becoming serious shooters realizing that it takes practice and repetition.

 

[HighUintas]

These newer brass companies (alpha, adg) are making their heads much harder than the older companies do (Hornady, Winchester, etc) and the fat bodied magnums (saum, wsm, prc) are maybe a bit more popular now. The harder and fatter heads are supposedly harder to size that web area with the design used in "traditional" dies.

You CAN get custom Hornady dies made that will size that area just as a micron, SAC, or Cortina die will but you'd very likely have to call and spec the die out. Alex Wheeler has mentioned many times that he likes Hornady custom dies because they work well and they will actually make them to the specs he requests, i.e. the prcW chamber and Hornady sizing die.

Here's some measurements with the EC mandrel die. When I used it after the FL die it moved the shoulder forward by 0.001 because I moved a LOT of brass in the web. You likely won't see any change from the mandrel die if you use it every time, so long as your loads aren't so stupid hot you're blowing the web out 0.003 each firing.

This is a fired unsized case. That bright line is right around 0.270... it's where the solid head transitions to the wall and is the fattest part of my case because the chamber was cut too big. It measures 0.5025 and 0.503 on some cases. The head right above extractor groove (close to 0.200 line) measures 0.500. my regular FL sizing die was also cut too big and doesn't touch the case below that bright line at 0.270. This causes me sticky extraction, similar to clickers, even with mild loads because my regular FL die won't size that tough 0.270 area down enough. It will only get it down to about 0.502.



Here's a case I used the EC mandrel die on. It now measures 0.4995+ at that 0.270 area and 0.4995- at the 0.200 line. I haven't shot any after using the mandrel die yet because I'm getting the chamber fixed and a new FL die made, but I'm 100% confident I can put a hot load in there and won't have any extraction issues. It's very close to virgin dimensions (0.499) at the 0.200 line now. Earlier in the case's life, I could put a load in there that was way too high on pressure and not have an extraction issue, even though that's not what I typically shot. I kept the pressure on the warm side but not crazy. That former was just for pressure testing. The reason I started having the problem was because of multiple reload cycles where my die wasn't sizing that portion enough... It eventually grew too large and won't give enough clearance for a loaded round.

 

[SloppyJ]

@HighUintas

Would you mind stepping through your process for us and include the dies you use. Bushing or FL mandrel?

Is this standard across all of your cartridges or are you only using the mandrel die for cartridges prone to these issues?

My first 30 shots through my 300prc gave me some horrible SD and ES numbers. I'm worried because I picked up 1x fired lapua brass and I'm hoping I don't have these issues since they were fired in a different chamber. I'm using a Forster FL sizing die and haven't had any problems yet but I haven't shot more than 30rds.

 

[HighUintas]

@HighUintas

Would you mind stepping through your process for us and include the dies you use. Bushing or FL mandrel?

Is this standard across all of your cartridges or are you only using the mandrel die for cartridges prone to these issues?

My first 30 shots through my 300prc gave me some horrible SD and ES numbers. I'm worried because I picked up 1x fired lapua brass and I'm hoping I don't have these issues since they were fired in a different chamber. I'm using a Forster FL sizing die and haven't had any problems yet but I haven't shot more than 30rds.

This is only for my 30-284ai. Custom everything. I own the resize reamer and designed it to avoid the clicker issue, but the die was cut too big, so I've got issues.

For that one, the die has an expander ball and decapping pin, so I just use it like that to cut down on steps. I've never found the need to separate the sizing and neck expanding steps. I anneal each firing with that cartridge. The EC mandrel die will likely get used every reload when I get the gun and new die back.

So it's really just standard reloading with no special processes other than that EC mandrel die.

The other rifle I have is a factory 6.5cm Tikka. I use Lee FL dies for that because they work and they're cheap. Lee case lube. Bump shoulders 0.002. the only downside to those dies is they size different parts of the case (shoulder diameter and neck) more than needed and will likely not give me as many reloads as I want due to case wall thinning.

I can't speak much to your prc and brass. I don't have that cartridge. If all case dimensions are the same after sizing and you're seeing high ES and SD, I'd guess it's something to do with the powder/bullet/primer combo.