Body Dies vs FL Dies

[Shynloco]

Ok Guy,
Got a consensus question - I use primarily Redding Dies for resizing and Wilson In Line dies for seating bullets. But regardless of the caliber, why is it that even when I use any of my Redding FL Dies that I cannot get my freshly FL resized casings all the way into the corresponding Redding Body Die by hand? And yes I know the difference in use of these dies and what they do, but why the difference in the base area of the casings allowed by the different dies. I've considered spring-back but find it hard to believe it's that alone. Thx!

Alex

 

[Milo 2.0]

Are you lubing them up before trying? If you were to wipe the lube off, the case wont go back in your fl die either.
If you have the tools, you could measure the inside diameter of both dies, I'd say they'd be the same though.

 

[Shynloco]

Are you lubing them up before trying? If you were to wipe the lube off, the case wont go back in your fl die either.
If you have the tools, you could measure the inside diameter of both dies, I'd say they'd be the same though.

Milo,
I just amended the post a bit to clarify. I've asked around before locally and gotten all sorts of different ideas. And it's not a lube issue as it takes measurably more pressure on the lever of the press to run it through the Body Die right after the FL Die. But I'll go measure them to check, but this difference issue is the same in six different calibers. Thx!

 

[CatShooter]

Ok Guy,
Got a consensus question - I use primarily Redding Dies for resizing and Wilson In Line dies for seating bullets. But regardless of the caliber, why is it that even when I use any of my Redding FL Dies that I cannot get my freshly FL resized casings all the way into the corresponding Redding Body Die by hand? And yes I know the difference in use of these dies and what they do, but why the difference in the base area of the casings allowed by the different dies. I've considered spring-back but find it hard to believe it's that alone. Thx!

Alex

A body die is just FL die without a neck section or decapping rod.

When you FL size a case, it will NOT go back into the die it just came out of. There is some spring back.

That is just the way it is.

 

[Shynloco]

A body die is just FL die without a neck section or decapping rod.

When you FL size a case, it will NOT go back into the die it just came out of. There is some spring back.

That is just the way it is.
[/quote]

I'm well aware of the differences in the dies as stated in my original post. So apparently you support the springback theory.

Anybody else?

 

[Milo 2.0]

I only have a caliper, or I'd measure mine, I have the same for all my dies too.

Ok, I just measured my 6.5x47 dies with a caliper, the fl & body both measure .466". It's not the right tool though.

Try one case in each, then measure case body to see if there's a diff.

 

[Shynloco]

I only have a caliper, or I'd measure mine, I have the same for all my dies too.

Ok, I just measured my 6.5x47 dies with a caliper, the fl & body both measure .466". It's not the right tool though.

Try one case in each, then measure case body to see if there's a diff.

OK..Thx for doing that. Now try and see if you can insert that casing into both dies and see if the Body Die feels tighter or won't allow going all the way in? I've done the same exercise before and can't get the same measured casing into the Body Die before applying more pressure to the press handle and it goes into the FL die easily. Just weird to me (and yes I'm weird sometimes). Thx.

 

[Milo 2.0]

I only have a caliper, or I'd measure mine, I have the same for all my dies too.

Ok, I just measured my 6.5x47 dies with a caliper, the fl & body both measure .466". It's not the right tool though.

Try one case in each, then measure case body to see if there's a diff.

OK..Thx for doing that. Now try and see if you can insert that casing into both dies and see if the Body Die feels tighter or won't allow going all the way in? I've done the same exercise before and can't get the same measured casing into the Body Die before applying more pressure to the press handle and it goes into the FL die easily. Just weird to me (and yes I'm weird sometimes). Thx.

I didn't size and measure cases, I just measured the 2 dies?
To me, you're splitting hairs. I never use a body die, I just have them in case I have loaded rounds that wont chamber, I'll body size them before pulling bullets.

Even if you're scrunching the diameter of the case a little, it's no way as harmful as over bumping the shoulder.

 

[Shynloco]

Milo,
You are right on about me splitting hairs. I've become anal as hell since getting into "precision reloading" and as my FTR buds tell me, I've become my own worst enemy. Now admittedly, I'm not the sharpest pencil in the drawer, but things like these oddities bug me and I try and find an answer. I do appreciate the responses as I try and find rational reasons why things happen and why what "should" in theory, works in one of the same size, but not in another of the same size since I'm talking the same manufacturer of products. Thx!

 

[Milo 2.0]

Do let us know what you find out

Most of the guys on this are way more objective than myself as to the levels they take loading. I'm not a br guy, though I do strive to shoot accurate ammo and guns.
My discipline and that of my friends is shooting steel, and a hit at the bottom right corner scores the same as a center punch.
Anyway, all these discussions on here make a guy re-think his process, not that I'll ever run this test, unless I have ammo that wont feed.
Hope you sleep tonight!

 

[bigedp51]

Shynloco

In another forum the topic of "spring back" was being discussed when the OP was asking "why" his resized cases were different lengths, base to shoulder after full length resizing.

One of the members posted a youtube video of a person counting to three before starting the down stroke of the ram on the press. The youtube video cartridge cases had more uniform case length and less runout.

The cases were resized once counting to three, then rotated 180 and full length resized again counting to three. The ball expander was removed from the die and not used. All of these cases resized this way were more uniform and had less runout. Stopping at the top of the ram stroke and counting to three tells the brass to stay put.

Bottom line, your answer is spring back.

And each die is a little different in size, and when you have three five gallon buckets of .223/5.56 once fired brass, fired in hundreds of different AR15 rifles none of the cases wants to be the same either.
(this is the worst thing that can happen to someone with brass OCD)

P.S. I'm retired with nothing to do and all day to do it, and I asked myself the same question you did here. So start counting to three and don't sweat the small stuff.

 

[Shynloco]

Thank you my friend for the suggestion. Sounds like you do many of the same things I do. As to the counting thing while resizing, I already do that and have been since I first starting using Body Die a few years back...found it definitely helps with concentricity. I also check for concentricity on each case I resize and do the 180 degree rotation thing on my casings. In fact, one thing an old timer taught me recently is that with my 6.5, my best consistency and accuracy, is where I turn the necks to .012. After that, a few of my Lapua Necks after resizing end up with not so hot (.006 - .008) concentricity. So what he taught me was to first re-anneal those pieces of brass, lube that baby and run it through my Body Die and then it through my FL die, slowly turning the case 5 times (I try to turn the case 1/5th each turn. Now I'm NOT rebumping the shoulders because I've back the die off a tad after relocking the lock ring) but through that slow turn/5 time hit process am successfully able to rehabilitate that piece of brass and getting it down to .003 concentricity for loading. Now if after all that, that piece of brass still won't give you a "reasonable" loaded concentricity of .002 - .003 runout after firing it, toss that baby in the trash because she'll mess with you downrange and aggravate you til the cows come home. Just some more of the insane stuff I do chasing that dime sized group on each and every target. Now you get a flavor of why my FTR buds tell me I'm driving myself insane chasing perfection.

 

[bigedp51]

I'm sorry I can't find the youtube video link "BUT" if you resize without pausing at the top of the ram stroke spring back has a greater effect and the video showed this in detail.

What surprised me even more is after the cases sit after sizing for a few days they continue to "grow" or "shrink". The shoulder bump will increase or get longer and the neck diameter will decrease or get smaller.

Cases that fit on my Sinclair case neck gauge after sizing would be too tight to fit on the gauge after sitting a day or two.

This shrinkage keeps happening as we get older but we never talk about it and just keep bragging. : That gives me an idea, I'm going to mix Viagra with my resizing lube and see if it effects the spring back rate.

Note to self, contact Boyd Allen on this subject and get advice.

 

[Shynloco]

This shrinkage keeps happening as we get older but we never talk about it and just keep bragging. : That gives me an idea, I'm going to mix Viagra with my resizing lube and see if it effects the spring back rate.

AIN'T THAT THE TRUTH! Novel idea....try not to hurt yourself or end up in ER.......

 

[sailhertoo]

Seems like sizing the same case 5 times, turning 1/5 turn each turn, would over work your brass. It would definitely cause your brass to grow way long and have to be trimmed. Lose a lot of brass that way I would think.

That being said, I'm going to try turning 90 degrees and sizing twice after what you said.

 

[Shynloco]

Seems like sizing the same case 5 times, turning 1/5 turn each turn, would over work your brass. It would definitely cause your brass to grow way long and have to be trimmed. Lose a lot of brass that way I would think.

That being said, I'm going to try turning 90 degrees and sizing twice after what you said.

I'd say I have to agree with your thought process. But since I'm not really changing any shoulder settings in terms of bumping, I'd rather attempt to correct the concentricity for better accuracy and if my brass doesn't last as long, so be it in the bigger picture of what I'm attempting to do. This 5 section turning process is new to me also, but I already know what poor concentricity does to my targets and that doesn't make me happy and just wastes bullets and powder. And I've not had length growing issues. I'll go buy new brass any day just to have nice tight and consistent groups. Guess that's just part of why it's been said that reloading is not a poor man's sport. Thx for your thoughts as well.

Alex

 

[Milo 2.0]

I was going to mention rotating your case 180 degrees and repeating on the really unruly ones, but I don't think it will get your brass into the body die any easier.

 

[bigedp51]

Seems like sizing the same case 5 times, turning 1/5 turn each turn, would over work your brass. It would definitely cause your brass to grow way long and have to be trimmed. Lose a lot of brass that way I would think.

That being said, I'm going to try turning 90 degrees and sizing twice after what you said.

With the expander button removed your not over working the brass with each sizing operation done one after the other. I only rotate my cases 180 sizing twice with a expander button turned down to .221. The expander button barely touches the case neck on the down stroke. These cases are for a AR15 which needs a tighter grip on the bullet and no crimping.

Much of my once fired .223/5.56 brass has uneven case wall thickness, and is a cheaper grade of brass. With brass like this you may get good runout readings from the neck area but once the bullet is seated the runout gets worse.

This always makes me think about what I read at "The Rifleman's Journal" and Germán A. Salazar's shooting buddy saying.......

"I get the best accuracy when the case fits the chamber like a rat turd in a violin case"

This I take it to mean full length resizing gives your bullet a little wiggle room to be self aligning with the bore. (sidewall and headspace clearance)