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Picture of henryrifle
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My reloading journey to this point has been interesting but like so many past avocations there are many more levels of complexity and/or choice that are hidden to the beginner. Sometimes these are just choices but sometimes these choices represent measurable improvements to the end result.

In a recent thread here I learned about Redding Type S dies and neck sizing bushings. Having only used standard sizing dies with an expander ball, the bushing sizing concept sounds like a good improvement. While not difficult to manage, if you use different brands of brass you may need different bushings.

It looks like there is yet another way to size the case necks using a mandrel or expander. While I am not looking to further complicate a multi-step process, it does seem to me that the expander die may be a beneficial change as there would be no need to manage mandrel sizes for different brands of brass and maybe the mandrel cleans up some irregularities inside the neck.

I am looking for a way to incorporate my Dillon 550 into precision rifle cartridge loading (my definition of precision) that adds efficiency to the process but I have not found a way to do that yet.

If decapping prior to tumbling in SS media didn’t do such a great job of cleaning the primer pocket and flash holes, I could see decapping, full length sizing and using a mandrel to neck size taking up three spots on the Dillon after tumbling. No one sizes dirty brass right?

What do you all think about finishing the sizing process with a mandrel and do any of you incorporate a progressive press into your precision rifle reloading process. I am only loading .308 and 6.5 Creedmoor rifle cartridges.

Thank you in advance for your time and expertise.

Henryrifle
 
Posts: 491 | Location: Atlanta | Registered: November 11, 2009Reply With QuoteReport This Post
Alea iacta est
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Well now hold on there just a minute, slim.

Mandrels aren't used for "sizing", per se. Mandrels are designed to expand the neck of the case. I have K&M mandrels on my bench for every rifle caliber that I load for. I run brass over them after they've been cleaned, before I anneal them. Why? It makes sure the inside of the case mouth is round. Shooting field matches like I do, cases eject onto rocks, they get stepped on, they get crushed in my match bag, all sorts of stuff.

When you size brass with a bushing die, you do NOT use the expander anymore. Expanders are bad. The whole concept is poor - basically, you size the case neck smaller than it needs to be, while the expander is inside the case. Then, as you pull the case out of the die, the expander ball is dragged back through the neck to size it to the final size it should be. Yuck!

Using a bushing allows you to have that fine level of control over exactly how much the neck is sized, so you don't want to go fuckin that up by dragging an expander back through there after you just finished setting it RIGHT where you want it!

After this explanation, hopefully you are seeing the inherent issue, and why you'd want a mandrel. If the case mouth is dinged in any fairly significant way, since you are only pushing on the outside of the neck with a bushing die (you took the expander out, remember?), there's no way to remove that ding in the case mouth.

Hence, mandrel.

Mandrels don't really clean up irregularities on the inside of the neck. For that, you want a reamer. And if you want to clean up irregularities on the outside, you want to neck turn. I do not do either of those steps, that's getting too far into benchrest territory for me. I don't know if Nikon does either, but he *might*.


To answer your last question, if you finish the sizing process with a mandrel, your bullets will fall into the case. Smile
 
Posts: 15665 | Location: Location, Location  | Registered: April 09, 2012Reply With QuoteReport This Post
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Picture of henryrifle
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Hmmm. ex1976, what you are saying is true, of course, but there is a mandrel for expanding the neck for the purpose of bullet seating. Maybe only Internet idiots use that method but there are several seemingly reputable sources that are using a mandrel sized one thou smaller in diameter than the caliber and they are using it to more closely control neck tension.

Henryrifle
 
Posts: 491 | Location: Atlanta | Registered: November 11, 2009Reply With QuoteReport This Post
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The mandrel I use is .002 under size and I only use it to round out the mouths of any dinged case. For virgin brass, I push the mandrel through all the cases because they do get dinged in the blue box. After that, I will only use the mandrel to take out dings that I cause when I drop a case during processing and even then it will only be the first few hundredths of inches for the mouth.

I do not turn the necks on my brass, and I only use the bushings to set my neck tension, not the mandrel.

But if you want to do another operation, then by all means, do so if it makes you feel better.

Also, unlike exx1976's brass, mine never touches the ground. I do not even have an ejector in my F-TR rifle; I pick out each piece of brass from the bolt face and place it directly in the ammo box. If it got ejected and got the treatment that exx1976 describes, that mandrel would get used a lot more than it does now.

I anneal after every firing and then resize and deprime the brass in one operation. My brass is never dirty. I tumble in walnut after resizing and that takes away the annealing rings and polishes the brass nicely.

Adding more operations is not something I do lightly. Pointing bullets was the only one I added recently. I try to minimize the steps instead of adding to them.

This is something that I learned from the 2013 F-Open national champion; he's a good friend of mine and he told me that he does indeed try to fuss less with his brass and work more on keeping everything consistent.
 
Posts: 3398 | Location: Texas | Registered: June 20, 2012Reply With QuoteReport This Post
Alea iacta est
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quote:
Originally posted by henryrifle:
Hmmm. ex1976, what you are saying is true, of course, but there is a mandrel for expanding the neck for the purpose of bullet seating. Maybe only Internet idiots use that method but there are several seemingly reputable sources that are using a mandrel sized one thou smaller in diameter than the caliber and they are using it to more closely control neck tension.

Henryrifle


Speaking strictly about rifle cartridges - yes, those are internet idiots. The process you describe is the exact same as leaving the expander ball in the die - you're going to size the neck smaller than you want, then expand it back out again - except that now you're expanding the neck as another step, making your process take longer for no benefit! (not to mention, of course, that you're working the brass more than necessary - kind of makes anealing a necessity at that point!)

If you want the neck 1 thou larger, then buy a bigger bushing.
 
Posts: 15665 | Location: Location, Location  | Registered: April 09, 2012Reply With QuoteReport This Post
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Picture of henryrifle
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Thanks for keeping me straight. On a related note, My Redding Type S die came in with a few bushings for the different cases I use.

I loaded a few .308 rounds and WOW! What a difference in the feel of the press. There is no more double bump raising the ram and all the drag from the expander ball being pulled through the neck is gone and replaced with a smooth release.

For now, I like reloading again!

Henryrifle
 
Posts: 491 | Location: Atlanta | Registered: November 11, 2009Reply With QuoteReport This Post
semi-reformed sailor
Picture of MikeinNC
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^^ Yup. recently got a redding die for 223...I use the same LC13 brass for all my bolt action gun-so the brass should all be the same thickness...

I'm thinking of getting a redding die for my 243...but I'd have to start with a lot of new brass-so I will wait until I wear out the brass I currently have for that gun



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Posts: 11246 | Location: Temple, Texas! | Registered: October 07, 2006Reply With QuoteReport This Post
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