Help - Resizing Lapua 308 Win Palma (small primer) brass to 260 Rem for 260 AI

[michaeljp]

Thanks mate,
I'll give it a go as you described. And yes, im using the equivalent to H4350 which is ADI AR2209. I loaded some up the other day and tested them using 140gn berger hybrid target. My best group was .250". 0.02" jump, 3 shot group with 37.5gn of AR2209 at 100yards. I also use the free recoil method of firing and squeeze the trigger and trigger guard together. I did try some H4831 or ADI AR2213sc the best i got with it was 0.381 and 0.371 that was with 260 lapua brass. These were the first trial loads in this rifle, so i have a fair bit more experimenting to do with other projectiles aswell.


Thanks for your advice.

Hey mate I think from memory about 42gr 2209 is a pretty common accuracy load with the 260 so your 37.5 is pretty low. I would juice it up a little. Also I found the hybrid liked 5-15 thou jump with a bit more neck tension like 2-3 thou or a jam with 1 thou. The jam 15 thou and 43.2gr 2209 with the small primer cases in my 260 improved just placed me 2nd in the WA Queens prize after dropping 6 points at 300yds due to a scope issue. The load and gun was working beautifully.

Gday mate,
I trialed loads from 37gn - 40gn. The 37.5 was the tightest group. After that they started to open up. My neck thickness is 0.1500-0.1450. My loaded round at the neck is 0.294-0.295 im using a 0.291 bushing. My base to ogive measures 2.3350". I might just do another trial and see how it goes. That was with lapua 260 brass.
I just resized some palma brass with my 260 fl die, but im not real happy with the way they look. Im looking for a 7mm 08 fl die and try it in 2 steps instead of 1.

 

[Erik Cortina]

Sorry to break up the party...

I turn my walls down to .012" for my tight neck chambers, for a factory rifle there will be too much clearance and if you don't anneal you will split necks. There is also the possibility of poor seal around the neck and get gas blow by... DANGEROUS!

Now, you should not have a "brass build up" at the base, what happened is that you didn't size the neck down completely, so what you are doing is turning that portion of the neck thinner than the rest. If you turn it too thin brass will separate at that portion and when you extract the round the neck will stay in the chamber. It is also DANGEROUS by the way.

So, STOP doing what ShootDots suggested and lets see what you did.

Are you using a bushing die to do this with? A bushing die will not size the entire neck down, you need a non bushing die to do it right. If you read my previous reply, you will see the correct way to do it. I have done thousands of pieces of brass for wildcats that required this to be done, and what I outlined is the correct way.

MichaelJP, you have to measure what you have in hand and fit your components to your chamber. You can't just take what someone told you online and "just do it" without knowing what you are doing. You need to figure out the size of your chamber neck, then turn down to allow about .005" - .006" total neck clearance.

Good luck and stay safe!

 

[michaeljp]

Thanks Erik,
i am using a Redding 260 rem FL die, NON bushing type. First i start off with the die a fair way out and slowly turn it down with each stroke. I get to a point where if i turn it down more ii crush the neck completely. Im guessing its the 260 die causing this and i have just put an add out for a 7mm 08 FL die to do it in 2 steps. Ill wait till i get the 7mm 08 die before i try anything else. If i still get these bulges at the neck/shoulder junction ill give it away and just use the Lapua 260 brass. I was never going to turn the necks down to 12 thou. I know that that was way to much clearance around the neck in the chamber for a factory rifle.
Ive attached a photo of my results. The case on the left is the best i can get. The one on the right is crushed down when ive turned the die down too much.

 

[Erik Cortina]

Are you using expander mandrel before turning the necks? I would stop what you are doing immediately, those necks look really bad.

 

[michaeljp]

These are virgin 308 palma brass sized down in a 260 FL die, no neck turn, yes the expander was in the die.

Thanks for your concern, but dont be worried i wouldnt load these cases at all as i know something is wrong. I only started to look at sizing the brass down first,

 

[BradY]

Mick

Virgin cases for me end up way above 295 and my chamber is 298. Im guessing they would be close to about the same. NO WAY would I ever use them unturned. To me when necking down cases, I like the idea of turning just to make sure everything is straight and even. But in a situation like this you need to turn the necks as its just way too close to the chamber. Most factory chambers would be no larger than 298 I would think as remington and federal brass is smaller in diameter than lapua. Standard 260 lapua loaded up to 295 for me. The 308 necked down is more.

If your happy doing virgin brass to 260 (I still prefer 7-08 then 260) you will need to run you cases over an expander mandrel like the K&M first. The mandrels in a normal reloading die arent suitable for this. They open the neck up larger to suit the mandrel on K&M neck turners so you get a perfect fit on the neck turner and all your cases are cut consistently.

I cant see that photo all that good but it looks to me like you need to size further down the neck.

When I do mine I lube the case really well, and use a 7mm-08 FL sizing die. Then I re lube and use a 260FL sizing die. Once that is done first thing is an expander mandrel and neck turn. Then I will trim cases to consistent length, do the primer pockets and flash holes and finally necksize and load the case. Its a bit of full on work but for F class thats what you do. If I was hunting with them I wouldnt bother necking down cases but for arguments sake saying I did, I would discount the primer pocket prep and flash hole uniform. But the rest of it is needed. I run 293 loaded rounds in a 298 neck chamber. And thats with a 292 bushing in a type S FL die set to bump the shoulder back 0.5-1 thou.

 

[michaeljp]

If i size down further i crush the neck or get a pronounced flat edge in the shoulder. Ill wait and get a 7mm 08 fl die and try again. I may just give up on this idea and stick with the 260 lap brass.
Another thing ive just forund out. Im sitting here reloading the 260 rem cases to replicate my previous loads and increased some loads up to where you said 42 and 43 the max. My rifle is a Tikka super varmint 260 rem. Now i always use Wilson dies, in my 6ppc, 308 and 204 and until now 260rem. I neck sized the once fired lap 260 brass no probs. Then when i went to seat the projectiles the case wouldnt fit all the way into the Wilson seater die. I measured the webbing of the once fired and a virgin case and its a few thou larger. So i full length sized the fired case and it went almost all the way in the seater die. About 1 thou out. This looks like the first caliber that i need to full length size after each firing. Is this the case with you? You probably dont use wilson dies but do you FL each time you reload?

 

[timeout]

Are you using expander mandrel before turning the necks? I would stop what you are doing immediately, those necks look really bad.

These are virgin 308 palma brass sized down in a 260 FL die, no neck turn, yes the expander was in the die.

Thanks for your concern, but dont be worried i wouldnt load these cases at all as i know something is wrong. I only started to look at sizing the brass down first,

I believe that you have misinterpreted what Erik stated when he asked if you used an expander mandrel. That is a complete seperate step and piece of equipment than the expander inside of your FL die. I'm not trying to discourage you, but from the looks of those photos and mentioning of neck thickness to be 0.1500-0.1450, it would behoove you for safety sake to find a mentor locally. Things can go horribly wrong when working with standard handloads, let alone modifying components from standard to custom.

 

[ShootDots]

Michael.. I just saw the pics of those pieces of brass... Something is VERY WRONG there... DO NOT USE THAT BRASS! I have never seen brass look like that! When I did mine, they looked like any other piece of "normal" brass and fireformed perfectly... Those do not look even remotely like "normal" brass... Something is terribly wrong. I have never had problems necking down, however, Palma brass has VERY thick necks, and they are 30 cal.. I am not a fan of using any bushing die to neck anything down>>>I use them after they have already been necked down. Bushing dies are designed to neck MOST of the way down the neck>>BUT NOT all the way down.. I wish I could spend a day with you to see what's going on and use the dies I have to form that brass properly. At any rate, STOP using that brass and go back to the drawing board... Find someone in Australia who has experience in that area and get their help.

 

[spclark]

But i ended up with a very small step in the shoulder. Is this normal or did i turn to deep?

Saw those pics & agree there's a problem there! Those cases are ruined so go no further.

Cases radically reformed from parent brass MUST in all respects retain the characteristics of factory-formed cases as you progress thru the sometimes numerous steps necessary to get good-shooting & safe cases in the end.

It's considered good practice to take a little bite off the shoulder when doing neck turning, which is why companies making turning tools offer cutters with different angles on their cutting edges to work properly with certain shoulder angles.

The key concept is very little here, may not even be enough to cut around 100% of the shoulder's circumference. Once the brass is fired what you call a step ought to flatten out.

I've made fine-shooting 6XC cases out of Lapua's Palma brass. Inside neck reaming was necessary to keep neck thickness & uniformity under control before the last few forming / neck turning steps. I suggest this may be a little better than using a neck mandrel to force excess brass to the outside where it can then be turned off, but have no definitive info to support this just gut feelings.

When I started in on that endeavor I ruined a few cases too whilst working out just what steps needed doing and with which dies I had already on hand. I still have a couple of those around someplace I think & will try to locate them then post a picture.

As for small primer hang-fires: never had one in those 6XC's or far more often fired Palma rounds since the Palma brass became available.

 

[BradY]

I only use a wilson seater. The rest of the resizing is done with a type S FL die set to bump the shoulder back half to one thou each time. Consistency is key in my game and if each case is a whisker under that of a fired round, I know I have easy closing of the bolt, easy opening of the bolt and that my gun wont get disturbed in the bags.

 

[michaeljp]

Gentlemen,
I appreciate what you are saying to me, but please dont think im a fool and would try to use those case in the photo. I would not. They were my first attempt to neck down a 308 case in a 260 FL die.This is NOT a bushing die. I can see that something is wrong in what im doing. I have gone no further than necking down a few cases and would go no further until it get the process right. The steps im taking are lube the 308 brass, i them put it in the press and try to full length size it an 1/8 or less of a turn at a time until i get close to the neck/shoulder junction. Im thinking the 260 rcbs die is just to tight to get an even neck size all the way down. Thats why im waiting to get a 7mm 08 fl die to use before i use the 260 die. I havent gotten to the expander or neck turning step yet. I know about neck turning as i do it for my .262 tight neck 6PPC rifle.

 

[Erik Cortina]

Take the expander ball out of the 260 die. Then come back with expander mandrel used for neck turning.

 

[RonS]

Gentlemen, I am anticipating this same project in the near future, but after reading all of the comments, I have a question or two. Can a couple of Lee Collet dies (7-08 & 260) be use to reduce the .308 brass to .264 and then trim the neck to the proper thickness? If not, why? Just a thought.....

 

[spclark]

I don't use those particular products but my experience using Lee Factory Crimp dies leads me to think the range of sizing available in both may not be enough to move the neck brass far enough, i. e. the 308 won't get the neck small enough to fit the 260 when opened up all the way.

Hopefully someone with more direct knowledge will refute this, or a query to the folks at Lee will get you the sizing range accommodated by their products.

 

[RonS]

I was referring to using a 7mm-08 collet die first and then the 260 Rem collet die to reduce just the neck. I will ask this question on Lee Precision's site.

 

[joshstix]

I've tried necking down standard Lapua .308 brass in this way with a Lee 7-08 collet die but it ends poorly. the collet lcks up half way down the neck because of the extra resistance of sizing the large neck down and you end up with the bottom half of the neck ballooned out.

Now I just use an RCBS .260 full length die and resize in one step, then use a K&M expander and turn the necks to the same thickness they were before necking down.

 

[alf]

I've made a lot of 260 and 7-08 brass from 308 Lapua.

First off, if you don't know your chamber's neck dimension, you're pissin' in the wind. Get some cerrosafe and do a chamber cast, and measure with micrometers, not calipers. Anything else is just a guess.

I just use plain 'ol Redding neck dies. I anneal first, then one trip in the 7-08 die w/o the expander. and once more in the 260 with the expander. I then run the cases in the Sinclair mandrel, then turn to the appropriate thickness. Anneal again, and load away.

 

[dennisinaz]

Like Alf, I have made hundreds of 260 and 260AI brass from 308 Lapua; none from Palma brass however. I used a piece of R-P brass and fired it and measured it to get an idea on my neck (One neck was .294" and my new one is .297") I then neck turn the 308 brass in my Lyman neck turner to get rid of the extra metal- this insures that your brass is thin enough at the junction to NOT build donuts. I then size down in two steps using a FL 7-08 die and a FL 260 Die I then seat a bullet and measure it. Generally, I leave about .001-,0015 to turn off with my K&N turning. I chuck the brass up in my lathe and then turn the necks to the final dimension.

No donuts, usually and great shooting brass that last a long time. I anneal every 3 times I resize it.

Now that Lapua makes 260 brass and I re-reamed my chamber to a .297" neck, I can just use 260 brass with a light clean up cut on the necks.

IF, when sizing down, you get a donut, I use a 1/4" chucking reamer, held in my hand with my thumb against the outside of the neck as it is spun in my lathe about a 160 rpm to skive the donut off. Works like a charm.

I use R17 exclusively in the 260AI and can get 2860 fps with a 20" barrel shooting 140s. I get great ES and accuracy as well as velocity. H4831 is going to too slow for the small primers I think.

 

[Romulus]

Thanks for all the info and experiences. I've been working 12+ to 24 hrs a day and driving 250-550 miles so my project is going in baby steps.

I did some fireforming experiements using two drums, a 55 gal poly & a smaller perforated poly barrel, putting fiberglass insulation between. I did an ignition test on the insulation first and could not get it to catch fire.

The first fireform round I pulled the trigger on I thought misfired or was pushed out into an excessively headspaced chamber by the firing pin, but when I pulled the action open a wisp of smoke released and the positive pressure from the firing chamber wheezed out of my action. I didn't hear a thing! The shoulders were semi-spheres and quire interesting to a fireforming newby.

I stepped the grainages up using Winchester Supreme 243 brass and found a sweet spot where the shoulders looked pretty good. Not assuming the Lapua brass would behave the same I went through the process again with the Palma brass and found a different sweetspot, surprising to me in that the Lapua brass took a higher charge than the 243 Supreme brass.

At my decided fireforming charge the noise coming out of the firing chamber sounds like dropping a magazine or book on the floor. My light sleeper of a wife didn't gripe at all. ;D I'll measure the decibels on my next batch.

I went to measuring the necks after COW fireforming, turned one for practice on a 21st century lathe, seated a 120 TSX I had laying around, and then realized if I would barely need to turn my necks to get everything just right! I spent a lot of $ on the lathe that I would only use to shave my necks, lol. I've found the tool so simple and consistent and it has evaporated all the gripes and whining I've heard and been previously discourage by about neck turning.

Eventually I'll get around to some live fire, but the oilfield is crazy right now, and I'll be hunting some Mulies with the .284 Win early November. Hopefully I can get some load development done early or mid November. I have collected various powders and am trying to procure some GS projectiles. I will probably shoot 123s or 139s due to availability issues with almost all other options.

I'm just itching to get over the chrono with this project.