making .260 lapua brass?? advise please

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#1
I am preparing to rebarrel my 308 to a 260. I have alot of 308 Lapua brass, and I was wondering what steps I will need to take to neck the 308 down to 260. Will I need to turn the necks? Or would it be easier to neck Lapua 243 brass up to 260? Or would it be better just to sell all the brass I have and by Norma or Nosler Custom 260 brass.

Thanks in advance.
 
#2
Re: making .260 lapua brass?? advise please

Ahh yes the great debate.

Many have good luck necking up lapua .243 but I would prepare to neck turn as a donut will almost instantly form. I have had good luck with .260 Norma I have 6x firings on this brass and after 5x I had to run a mandrel through them to knock out the donuts and they are back to shooting 1 hole five shot groups. I also have some Nosler and they are within 1 grain weight difference of the Norma. My next step is to neck down Win. 7-08mm brass. As it is much cheaper than lapua and will hold up. BTW the Norma primer pockets are still going strong. I only found 4 out of 65 with primer pockets starting to loosen. But those are still usable. And I have hammered the hell out of them with some pretty stout loads. If you have more time than money them I would look at going with the Win.7-08mm brass. As the Lapua .308 you already have will be a PITA IMHO. If you insist on using the .308 brass then I would first neck turn them as .308 the full length size in a 7-08mm die then full length size in a .260 die then neck turn again. This is why it's easier to use the Win. 7-08mm brass. But I think he best and easiest thing is to go with Norma brass or Nosler brass for that matter. I think the Nosler will be just as worthy as the Norma.

There's always straight Remington .260 brass. I have not messed with it and do not plan on it. Others have had good luck with it and many have had to cull through a lot to keep worthy pieces. With Norma it's KISS. But it comes with a price. Hope this helps.
 
#4
Re: making .260 lapua brass?? advise please

lapua 308 necked down will be a bit short in the neck,the lot of rem 260 brass i have is very consistant in weight,ok but not great in neck thickness varation.i will probably go norma next time and keep praying for lapua to start making it.
 
#5
Re: making .260 lapua brass?? advise please

Necking down .308 (whatever) brass will leave you with a short .260 case, 2.015" case length for .308 versus 2.035" for .260. Is this something insignificant when doing so?
 
#6
Re: making .260 lapua brass?? advise please

Win 7-08 necked down. F/L resize 7-08 to .260, ream flash holes, fire once, prep is done. Works pretty much the same as Lapua, only without the alleged necking-up donut. The shorter neck is a plus; the case will have more firings before trimming becomes an issue. Never, ever saw any disadvantage doing it this way.

.308 brass can be necked down, generally in two steps; 308 to 7-08, then 7-08 to .260. Necks may be thick and require turning, which is why I prefer to start with 7-08.

Actually, Rem .260 brass is fine; the only issue I have had involves primer pockets opening up. Sticking to reasonable load pressures should reduce such tendencies.

If Lapua has an advantage, I think it's where case prep is concerned. Once that's been done with other brass, I believe the differences become a lot smaller.

Greg
 
#7
Re: making .260 lapua brass?? advise please

i have tried all 3 cases
rem shoots really well...
lapua ... higher velocity same charge than rem
but u will have trun the neck unless your barrel has a wide neck. mine loads them with .003 to spare. most wont though
7mm/08 no difference from rem

both lapua and win can be sized in one step...

again rem shoots really well
 
#8
Re: making .260 lapua brass?? advise please

I went with the rem and after some serious prep (but definately not more than turning 308 into 260) I am really happy. Low es dime sized 10 shot groups from my stiller. Only 3 firings so far but primer pockets still tight. You will love the 260.
 
#9
Re: making .260 lapua brass?? advise please

I own my own weight in 308 brass, but I am not necking it down to 260, now.

I have in the past, but some of the neck walls were too thick and I had unpleasant surprises popping up.

So I quit.

But the temptation to use Lapua 308 small primer pocket brass for 260 is strong [run 80kpsi loads instead of 65kpsi loads], and I am going to try again... As soon as I get faster, smarter, better at turning necks.
 
#10
Re: making .260 lapua brass?? advise please

As others have said, necking down 308 brass would be a bit arduous (for me anyway) to undertake.

I tried some Lapua 243 brass and expanded it up to 6.5 but had several necks split on me in short order.

The Remington 260 brass gets a bad rap by some, but that's what I've gone to w/ good results. Especially after firing once, then neck sizing on subsequent loads.
 
#11
Re: making .260 lapua brass?? advise please

I shoot remington out of the box with little prep, and no weight sorting. The only issue I have is pockets which eventually loosen, but that is managable.
Its cheap so when they loosen I toss them. There was a time when I was running them a little hot and getting little life, which bummed me out. I got over it and almost 4k rounds later, this is still the most accurate gun I have ever owned. More shooting, less loading fuss.
 
#12
Re: making .260 lapua brass?? advise please

I used to use Rem 260 brass but not any more, now I'm using Win 7-08 brass, the only prep I do is uniform the pockets, beburr the flash holes, after that all I do is run the 7-08 thru a Redding Type S FL die with a .290 bushing with a carbide expander ball, trim chamfer with my Giraud and load n go, accuracy is good on the first firing, after 10 firings most of the primer pockets are still tight, I was asked about donuts and have not experienced any, I don't neck turn, and I have found that the Win brass necked down to be more uniformed in thickness compared to Rem 260 brass, I did have to increase my powder charge .5grn to get back to 2800 fps with 139 Scenars
 
#13
Re: making .260 lapua brass?? advise please

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Clark</div><div class="ubbcode-body">I own my own weight in 308 brass, but I am not necking it down to 260, now.
But the temptation to use Lapua 308 small primer pocket brass for 260 is strong [run 80kpsi loads instead of 65kpsi loads], and I am going to try again... As soon as I get faster, smarter, better at turning necks. </div></div>

I am not sure how a small primer is going to allow you to run higher pressures. 80kpsi is a recipe for disaster. My opinion is that the small rifle primer is marginal for a 308 size case anyway. just my opinion
 
#14
Re: making .260 lapua brass?? advise please

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 427Cobra</div><div class="ubbcode-body">I used to use Rem 260 brass but not any more, now I'm using Win 7-08 brass, the only prep I do is uniform the pockets, beburr the flash holes, after that all I do is run the 7-08 thru a Redding Type S FL die with a .290 bushing with a carbide expander ball, trim chamfer with my Giraud and load n go, accuracy is good on the first firing, after 10 firings most of the primer pockets are still tight, I was asked about donuts and have not experienced any, I don't neck turn, and I have found that the Win brass necked down to be more uniformed in thickness compared to Rem 260 brass, I did have to increase my powder charge .5grn to get back to 2800 fps with 139 Scenars</div></div>

Just curious, did you have a problem(s) with the Rem brass? I tried necking down some 7mm-08 brass and noticed a spike in pressure vs Rem 260 factory brass. I figured it was due to the increased thickness of the neck wall from the downsizing. I didn't want to get into inside neck reaming so I just went back to using the Remington brass.

I know it get's bad press, but it's been plenty good and consistent in both my 260 Rem rifles. I do agree that the primer pockets seem to be a weak link. When loaded stoutly, the pp's get loose in a hurry.
 
#15
Re: making .260 lapua brass?? advise please

Rem brass is fine, and its cheap. I'd rather toss brass after 3-4 firings than have to neck turn and do a bunch of other reloading voodoo crap that won't make it shoot any better anyway.
 
#16
Re: making .260 lapua brass?? advise please

I would give the Remington brass a try. If it shoots good then you can always sell the .308 Lapua brass.

I just converted a 6.5x284 into a 260 Remington and the first tests with Remington brass turned out so well that I haven't bother to investigate any other routs.
 
#17
Re: making .260 lapua brass?? advise please

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Swan</div><div class="ubbcode-body">Rem brass is fine, and its cheap. I'd rather toss brass after 3-4 firings than have to neck turn and do a bunch of other reloading voodoo crap that won't make it shoot any better anyway. </div></div>

Nail on the head! FWIW, my load is 40.7gr of h4350 under a lapua 139 for 2800 in a rock 24". I can do the same with 41.7 of re17 with the same accuracy. "Reloading voodoo crap" couldn't have said it better myself.

Edited: Let the target tell you what you need, until it tells you otherwise, just stick to the basics.
 
#18
Re: making .260 lapua brass?? advise please

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Stiller</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Clark</div><div class="ubbcode-body">I own my own weight in 308 brass, but I am not necking it down to 260, now.
But the temptation to use Lapua 308 small primer pocket brass for 260 is strong [run 80kpsi loads instead of 65kpsi loads], and I am going to try again... As soon as I get faster, smarter, better at turning necks. </div></div>

I am not sure how a small primer is going to allow you to run higher pressures. 80kpsi is a recipe for disaster. My opinion is that the small rifle primer is marginal for a 308 size case anyway. just my opinion </div></div>
You want to re state that?
I find it hard to believe [and disturbing] you don't know why higher pressures are possible when the 1889 7.65x53mm Mauser case head used in a 260 goes from large Boxer to small boxer primer pocket.
What pressures did you think 6mmBR handloaders are running?
 
#19
Re: making .260 lapua brass?? advise please

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Cpl Snafu</div><div class="ubbcode-body"> "Reloading voodoo crap" couldn't have said it better myself.

Edited: Let the target tell you what you need, until it tells you otherwise, just stick to the basics. </div></div>

I have shot Cpl's 260 and it is a hammer...

I "waste" my time doing the benchrest brass prep deal...uniforming primer pockets, deburring flash holes, trimming to the same OAL, weighing EVERY powder charge, checking runout and sorting in .002" increments...then I watch Cpl Snafu throw charges from his powder measure without weighing, then the following morning stack rounds at 1K...so much for the reloading voodoo crap!

 
#20
Re: making .260 lapua brass?? advise please

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Clark</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Stiller</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Clark</div><div class="ubbcode-body">I own my own weight in 308 brass, but I am not necking it down to 260, now.
But the temptation to use Lapua 308 small primer pocket brass for 260 is strong [run 80kpsi loads instead of 65kpsi loads], and I am going to try again... As soon as I get faster, smarter, better at turning necks. </div></div>

I am not sure how a small primer is going to allow you to run higher pressures. 80kpsi is a recipe for disaster. My opinion is that the small rifle primer is marginal for a 308 size case anyway. just my opinion </div></div>
You want to re state that?
I find it hard to believe [and disturbing] you don't know why higher pressures are possible when the 1889 7.65x53mm Mauser case head used in a 260 goes from large Boxer to small boxer primer pocket.
What pressures did you think 6mmBR handloaders are running? </div></div>

Not to stir anything, but I would like to know what the real answer is on this. Anybody else care to weigh in?
 
#21
Re: making .260 lapua brass?? advise please

Had a phone discussion with a champion shooter who was into using small primer .308 brass. They abandoned the idea. Said that once they had adjusted the load with large pockets, the performance was identical.

Running higher than SAAMI pressures is a bad practice. Even if the brass will take the beating, the cumulative excess stress on the action will compromise its safety.

TANSTAAFL (There Ain't No Such Thing As A Free Lunch)

Greg
 
#22
Re: making .260 lapua brass?? advise please

I shot rem brass in my 260 after a little work it shoot fantastic

I took the trouble to trim, turn necks, chamfer, debur flash holes.

i believe the extra case prep is worth it, gun shoots pretty good
 
#23
Re: making .260 lapua brass?? advise please


Clark, you are absolutely right, but if you want people around here to like you, then you are going to need to back off from being right and allow them to indulge in typical internet forum behavior.

(I can't believe an action maker does not understand pressures. Maybe his kid is posting from his account.)
 
#24
Re: making .260 lapua brass?? advise please

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: mmedearis509</div><div class="ubbcode-body">I am preparing to rebarrel my 308 to a 260. I have alot of 308 Lapua brass, and I was wondering what steps I will need to take to neck the 308 down to 260. Will I need to turn the necks? Or would it be easier to neck Lapua 243 brass up to 260? Or would it be better just to sell all the brass I have and by Norma or Nosler Custom 260 brass.

Thanks in advance. </div></div>
Sell what 308 you have, and start over on the right foot.
This is a huge debate over what 260 brass is best. I have well over 5 reloads on my Remington 260 brass. Yes, there are a few that have loose primer pockets. This doesn't surprise me any, because I've done a lot of load testing with some going to max pressure. So I just tose that case.
If you prep Rem brass, it can be just as accurate as any other brand of brass. My 260 is a 1/4 MOA gun under ideal condidtions. I don't know how you can improve on this by going to another brand. I like the Nosler brass, and use it for my 300WM competition loads. But I lose a lot of cases, so it gets more expensive when you lose cases that you can't reload. That's why I run Rem brass. I don't like virgn brass, but you have to start somewhere. I like once or more fired brass where I can control all parts of the brass prep process. Anneal the case necks, trim them up, chamfer and debur, and keep your powder charge consistant. These steps are more important than which brass brand you go with. Spend more time prepping the cases the same than messing with neck turning, and all the crap that goes with that.
 
#25
Re: making .260 lapua brass?? advise please

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Clark</div><div class="ubbcode-body">You want to re state that?
I find it hard to believe [and disturbing] you don't know why higher pressures are possible when the 1889 7.65x53mm Mauser case head used in a 260 goes from large Boxer to small boxer primer pocket.
What pressures did you think 6mmBR handloaders are running? </div></div>

My point in this is that given a case head with the same dimensions for the web thickness, head thickness and alloy type and temper, the pressures that a small rifle primer allows should be similar to the large. 80kspi is approaching the flow point on most brasses. I understand pressures on cases and in the system well. I did not intend to compare the 308 lapua cases to the mauser type you talked about, only the same lapua cases in large versus small pocket.

I dont have a great knowledge of the particulars on the 260 rem head design or the brass used. I also dont know if the Lapua small and large primer pocket brass is dimensionally the same for the rest of the numbers, but assume it is. No matter what, 80kpsi is way too much. Handloading the brass much above its designed point is just not a good answer.

I shoot lots of PPC's and BR's at too much velocity. I have pockets that go bad in a hurry if I step on it too much. Too much according to my old Oehler 43 strain gauge setup was in the low 70kpsi range. Anytime someone talks about 80kpsi, I have to recommend that it is too much. I used lots of the old Rem 308 small primer brass in 308 turned to short BR in the old days before anything good was available. It was softer yet. A good lake city piece of brass would take pressure better then they would.

If making brass from a larger caliber, you also make sure you have at least .001 clearance all around the loaded round neck to the chamber and make sure that the end of the case isnt hitting the neck/freebore section. Either one will be a pressure diaster.

I guess I must be missing something if I am that far off base in my statement. By the way, I dont have any kids, and if I did, they damn sure wouldnt be using my computer.
 
#26
Re: making .260 lapua brass?? advise please

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Stiller</div><div class="ubbcode-body">

My point in this is that given a case head with the same dimensions for the web thickness, head thickness and alloy type and temper, the pressures that a small rifle primer allows should be similar to the large. </div></div>
I disagree.

While web thickness in the <span style="color: #FF0000"><span style="font-weight: bold">axial</span></span> direction is of primary importance in predicting the max pressure for pistol cartridges with feed ramp intrusion into the supported chamber, it is only of secondary importance in cartridges supported back to the web. Strong rifles support to the web, except possibly for CZ527 with 22 Hornet bolt face is chambered and over chamfered for the 19 Badger [30 carbine case head].

What is of primary importance in predicting the maximum pressure in Mauser case heads is the web thickness in the <span style="color: #FF0000"><span style="font-weight: bold">radial</span></span> direction at the weakest spot, where the extractor groove impinges from the outside and the primer pocket intrudes from the inside.

The reason that the Mauser case head with large primer is never SAAMI registered above 65kpsi is because of loose primer pockets e.g. 6mmRem and 270Win.

This cross sectional area is, from specifications, between 0.084 and 0.095 sq inches in the RP 260 brass and between 0.095 and 0.108 square inches in the Lapua small primer 308 brass.
There is not a random distribution of product thought the specified range, but rather a more predicable nominal of 0.095 sq in for the RP and 0.106 sq for the Lapua.

This 14% difference would suggest that if [the large primer pocket brass is registered at 65 kpsi, can get long brass life with handloads for individual rifles at 70 kpsi, and has one shot short brass life at 75kpsi], then [the small primer brass could be registered at 74 kpsi, have long brass life at 80kpsi, and get one shot short brass life at 85 kpsi]. But it is not perfectly linear, and 6mmBR brass will not get loose primer pockets before the primer pierces. I have a couple of these rifles and they pierce CCI450 magnum small rifle primers. Gre-tan offers a service to bush the firing pin hole to allow an increase in the pressure before piercing. There is no SAAMI registered pressure for 6mmBR.

Max pressure for brass case heads can be better calculated with von Mises calculations, which I do not do, but Scott Sweet does. I only have his calculation for the large primer:
"The Mauser case head nominal condition chamber pressure for the initiation of case head yielding with H06 C26000 brass is: 76,977 psi".
 
#27
Re: making .260 lapua brass?? advise please

I agree with you on the analysis. It is accurate if the primer pocket pressure follows the chamber pressure. The primer pocket pressure is probably not equal to chamber pressure though, and will depend on the flash hole size and the volume of the pocket. Given all that, the small pocket may still take a little more pressure than the large. But I still feel 80kpsi is too much. If the large primer pocket is being loosened up with a load, especially using Lapua brass, the load is most likely too hot for either pocket sized case in my opinion. In my lapua 6.5-284 cases I can get about 4 shots and the pockets are toast. I also get ejector pin marks extruding into the bolt at those pressures. I just dont see the need to push it so hard and take the risks associated with it.
 
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