zero headspace

[IDPA Mike]

I read this in a brass prep post. How do i get the neck to expand in the press. I followed the instructions that came with the die, and turned it to the bottom of the shell plate. I cant seem to get the neck to expand like the guy in the article. I only ask, because i am starting high power with a new upper and want to get the best rounds I can,

http://www.shell-central.com/Brass_Prep1.html

"we will expand the neck diameter enough that it will not enter the chamber, then adjust our sizing die down a little at a time until the neck is reduced enough to just allow it to chamber without resistance.

As we adjust the die down into the press, we will see the case neck step down to form a secondary shoulder and we will continue to advance the die downward about 1/4 turn at a time, trying for rifle fit as we go. Clean the case between sizing and the rifle chamber, to avoid introducing case lube into the rifle. When we find the point at which the rifle will close on the case with very little “feel”, we will be at zero headspace in that particular rifle. Turn the die down another 1/8 turn, and lock the die in that position. Test fit a few cases to ensure that they freely chamber."

Thanks , Mike

 

[mac1911]

thats way deep, read thru that link..........be a while before I reach that level

 

[EddieCoyle]

Bottleneck rifle cases headpsace on the shoulder, not on a secondary neck shoulder.

What type of gun will you be shooting?

 

[Dick]

As he indicates in the article, you do it by using an expander ball that's oversized for the cartridge you're working with. In his example, he suggests using a .264 ball for .243 cases. Are you sure you want to get into that? - it's pretty esoteric reloading technique that I doubt many rifle/shooter combinations can benefit from.

 

[38ExtraSpecial]

i didn't read the whole article but can't the same sort of thing be achieved by using once fired brass and adjusting your die (with the use of a hornady headspace gauge) so that you pretty much just neck size only, or go a little further and bump the shoulder back .001 ?

that sounds like an awful lot of stress on the brass.

 

[EddieCoyle]

The fact that you mentioned a 'new upper' in your OP leads me to believe that you'll be shooting an AR.

The article you linked to describes reloading for a bolt action benchrest gun, which is an entirely different exercise.

If you sort your brass by headstamp and number of times fired, use good bullets, and a good seating die (like the Redding or RCBS 'competition' dies) you'll be most of the way there.

Get an RCBS Precision Mic and use it to set up your sizing die and bullet seating depth.

 

[IDPA Mike]

The fact that you mentioned a 'new upper' in your OP leads me to believe that you'll be shooting an AR.

The article you linked to describes reloading for a bolt action benchrest gun, which is an entirely different exercise.

If you sort your brass by headstamp and number of times fired, use good bullets, and a good seating die (like the Redding or RCBS 'competition' dies) you'll be most of the way there.

Get an RCBS Precision Mic and use it to set up your sizing die and bullet seating depth.

I will be shooting an AR White oaks upper . What I do now is, deprime with the RCBS decapping lube die, resize with a Hornady sizing die,tumble clean,Check with the Dillon Rifle Case Gages. Trim if necessary, then load in the progressive. My long distance ammo I get the OAL with the Hornady Lock-N-Load Overall Length Gage Automatic . I make them so they just touch the barrel.
I just want the ammo I make to be as good as consistent and good as I can.
Thanks, Mike

 

[38ExtraSpecial]

the tough thing about doing this in a gas gun is that you sacrifice feed reliability. you can do these things on a bolt gun because you can push the bolt forward and cam it shut no problem, when the round needs to feed in a semi auto you'll run in to a lot of jams i would imagine.

go with what ED said and spend some time with your weighing and prep and you'll have amazing rounds for a bolt gun, and they'll all feed to boot.

 

[jasons]

As he indicates in the article, you do it by using an expander ball that's oversized for the cartridge you're working with. In his example, he suggests using a .264 ball for .243 cases. Are you sure you want to get into that? - it's pretty esoteric reloading technique that I doubt many rifle/shooter combinations can benefit from.

I really don't think you want to do that. Seems to me that you'd overwork the brass and get cracked necks and / or neck tension problems after very few firings.

A properly adjusted full-length sizing die is all you really need (for sizing cases) for an AR shooting highpower. This isn't benchrest.

 

[bpm990d]

He was talking about using a scrap/sacrificial piece of brass as an aid to setting up the shoulder to just bump the headspace to just fit the chamber.

This is an un-fireformed piece of 6.5 Grendel brass sized to 6mm RAT. That bulge is the false shoulder he is talking about in the article. It is what the case headspaces on for the first firing. After that the shoulder is blown forward, and it headspaces on the shoulder like a regular case. I need to do this because I'm forming cases from 6.5 down to 6mm. I'm not sure why he is doing it that way as there are easier ways to achieve what he is talking about. It's like asking a girl out to the prom, by telling your buddy to let his sisters friend know that you liker her. You can do what he is talking about without needlessly creating a false shoulder.

Anyways I agree about this not being benchreset. I would say that 85% of the accuracy you could ever achieve, is all about a quality bullet. You can fart around with primers/powder and seating depth to get the other 15%. I will say that you can greatly improve your brass life by using properly sized dies. Most commercial full length dies overwork the case necks. You really should send your die out to the manufacturer and have them hone it properly so it does not squeeze the crap out of the necks on the up stroke, or you can do it yourself. Here is a link to the stuff you need to do it.

http://rickaverill.com/projects-past-and-present/lapping-reloading-dies/

B

 

[Slowdive]

I think (as bpm990d was saying) the "false" or second shoulder refers to fireforming cases....so your not really looking for headspace per se. If you are trying to bump out a shoulder, you can size the neck to chamber while leaving the shoulder "unsupported". On firing the brass will push to fill the chamber. My guess anyway??

 

[EddieCoyle]

Most commercial full length dies overwork the case necks. You really should send your die out to the manufacturer and have them hone it properly so it does not squeeze the crap out of the necks on the up stroke, or you can do it yourself. Here is a link to the stuff you need to do it.

http://rickaverill.com/projects-past-and-present/lapping-reloading-dies/

B

I did that to one of my dies. I honed it to size the neck of Radway Green brass without overworking the neck. The problem is that it no longer provides sufficient hold for most commercial headstamped brass.

I recently started sizing my .223 using a Redding body die to FL size and set the headspace, then a Lee collet neck sizing die. The Lee die sizes the neck by squeezing it against a mandrel/decapping pin. It sizes the neck to a consistent ID regardless of the brass thickness - without overworking it.

The Lee die has two other benefits - one that I've already tested and one that I'm in the process of testing.

The case necks come out more concentric to the case body with the Lee die as opposed to either an RCBS FL X-die or a Redding bushing neck die. I've measured this, and it is pretty easy to maintain <0.003" concentricity with the Lee die. It's not so good with the others (which ranged up to 0.009" of non-concentricity with the Redding die). My groups are a bit better with brass sized with the Lee die.

I also anticipate that since the Lee die works the neck as little as possible, that they'll work harden as little as possible. Therefore groups fired with brass that was fired/sized a different number of times should be better. In other words, if I put a piece of 4X fired brass in with a bunch of 1X fired brass, I shouldn't get as much of a flier with it.

 

[bpm990d]

Very interesting. Brass does vary from manufacturer to manufacturer and as you know each die is a story into itself. Is the Radway Green neck thickness quite a bit different that say Winchester? I know you had a whole bunch of it.

I had a buddy that used a collet die when he made MexMatch from ball ammo. He basically pulled the bullets, dumped the powder and ran it into a Lee Collet Die then put the powder and a match grade bullet back in. I've never played with one, but thought the idea was interesting. The stuff he showed me had some interesting marks on the case necks, but I think you are right on about not working the necks. The concentricity issue is one I'd like to solve as I can load straight ammo in .308 and 30-06 but pretty much everything I make in .223 is crookeder that a Chicago politician.

B

 

[EddieCoyle]

The neck OD of Radway Green loaded with a 75gr AMax and sized on the Lee is .2485, the neck OD on Winchester brass with the same bullet sized on the same die is .2465, so the Radway brass is 0.001" thicker. Some other commercial brass is even thinner (Remington I thing and maybe Fiocchi).

If the marks you saw were 4 vertical lines on the neck, I bet it was because he squeezed it too hard. You can get a tremendous amount of leverage with a press - way more than is necessary to neck size .223. You develop a feel for how hard you need to squeeze it (and it's not hard at all). I squeeze it once lightly, rotate the case about 1/8 of a turn, then squeeze it again lightly.

 

[highscore]

Gas guns require a less than perfect fit of the cartridge OAL in the chamber. I try for .001 to .002 clearance on the shoulder. If the bolt won't fully close, your asking for trouble, including missing body parts. Reloading processes that bolt rifle shooters use aren't always safe for us gas gunners. Buy a tool that can measure shoulder length accurately and bump back your once fired cases .001 or .002. You have to use brass that was shot in your gun so it's been expanded to your chamber. Don't let anyone tell you that you can neck size only either. What are you using for components? Progressives are fine but how consistant does your powder measure throw charges?

For ammo I care about, I decap the brass and then tumble to clean. Then I resize using a Forstner Bonanza full length resize die using Hornady one shot for lube. Trim if necessary and chamfer both ID and OD of case necks. Clean primer pocket with brush type primer pocket cleaner chucked up in a drill press. Actually I run my chamfer tools in the drill press also. Sinclair sells a lot of really good stuff and their chamfer tools cut really well. Chamfers that leave a large burr are a waste of time. Chamfering the OD's may also be a waste of time but it makes me feel better about feeding. I then wash the brass at work in something that reminds me of acetone. Drys real quick and you don't want to put your hands in it!

If it's a really big match or when I used to load for my son who was pretty good, I would weigh out each charge and load them on the single stage. Not so big of a match, 200 and 300 yard ammo loaded on the Dillon 550 and 600 yard ammo still one at a time.

200 and 300 yard ammo, Varget, Sierra 77's, Federal 205m primers, seated to mag length
600 yard ammo, Varget, Sierra 80's, Federal 205m primers, seated .005 to .010 off the lands

LC brass is my favorite and WINCHESTER (spelled out, not WCC) and Federal are my least favorites

I've also expermented with Accurate 2460 ball powder wich works very well. I think there's a mention of the load on White Oak's web-site. Drops dead on in my Harrels measure.

 

[highscore]

He was talking about using a scrap/sacrificial piece of brass as an aid to setting up the shoulder to just bump the headspace to just fit the chamber.

This is an un-fireformed piece of 6.5 Grendel brass sized to 6mm RAT. That bulge is the false shoulder he is talking about in the article. It is what the case headspaces on for the first firing. After that the shoulder is blown forward, and it headspaces on the shoulder like a regular case. I need to do this because I'm forming cases from 6.5 down to 6mm. I'm not sure why he is doing it that way as there are easier ways to achieve what he is talking about. It's like asking a girl out to the prom, by telling your buddy to let his sisters friend know that you liker her. You can do what he is talking about without needlessly creating a false shoulder.

Anyways I agree about this not being benchreset. I would say that 85% of the accuracy you could ever achieve, is all about a quality bullet. You can fart around with primers/powder and seating depth to get the other 15%. I will say that you can greatly improve your brass life by using properly sized dies. Most commercial full length dies overwork the case necks. You really should send your die out to the manufacturer and have them hone it properly so it does not squeeze the crap out of the necks on the up stroke, or you can do it yourself. Here is a link to the stuff you need to do it.

http://rickaverill.com/projects-past-and-present/lapping-reloading-dies/

B

I experimented with something like this in my Palma rifle. Since I wasn't pushing the shoulders back (fired cases could be rechambered without much effort) I used a Redding full length resize die and left a small "step" just above the shoulder, it just wasn't as pronounced as in the picture. Sort of like neck sizing with a full length die. Correct or not, it worked for me.

 

[bpm990d]

So the reloading geek in me decided to try this, if for no other reason to prove to myself that it's the wrong way to go about something like this.

.308 Winchester Cases - Federal
Redding Expanding Mandrel and die .3362

What the mandrel looks like sitting on the case mouth.

Case after if was expanded. I've basically made a .338-08 if there was such a beast.

Next to a regular .308 case.

Case mouth.

Run it up into a .308 Winchester FL die.

And you get this monstrosity. If you screw the die down all the way, you just get a case sized to look like a regular .308 case. However if you keep it back several revolutions you get that false shoulder.

From the top. Case mouth with false shoulder on left.

B

 

[highscore]

The step left on my cases were somewhere between .005 and .010 in length. Just enough not to bump the shoulder back. Not as pronounced in diameter either. I also experimented with a neck size only die also leaving the step and didn't see any difference in accuracy.