Big news from Lapua

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Obtunded

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I read in accurateshooter.com that Lapua has two big additions to its lineup:

first of all they are making 308 brass with a small primer pocket - to be called 308 Win Lapua Palma brass and secondly, they will now be making 22-250 brass!

Time to dust off the 6XC and play with it some more!!
 
In heard they were going to start making it.What would the process be for fire forming 6xc brass from 22-250?I wouldn't have a clue how to do it.
 
Pardon my reloading newbie'esqueness, but what can possibly be attained by fitting a small rifle primer pocket to .308 brass? Use WSRM primers (or the equivalent)? What benefits would come of this?
 
Obtunded said:
I read in accurateshooter.com that Lapua has two big additions to its lineup:

first of all they are making 308 brass with a small primer pocket - to be called 308 Win Lapua Palma brass and secondly, they will now be making 22-250 brass!

Time to dust off the 6XC and play with it some more!!
Click to expand...

Remington used to offer thin walled 308 brass with the small pocket. The product was aimed at wildcatters and BR shooters. In my experience the only problem was using the brass in a full 308 on cold days the small primer didn't have enough jam to reliably ignite the cartridge. Tons of hangfires. Had to give it up. Should work great for smaller cartridges in the 30-40 grain range.
 
firemachine69 said:
Pardon my reloading newbie'esqueness, but what can possibly be attained by fitting a small rifle primer pocket to .308 brass? Use WSRM primers (or the equivalent)? What benefits would come of this?
Click to expand...

It has to do with making it more accurate when altering the 308 based case... like the .308 x 1 & 1/2 inches. The small primer is one of the things that makes the 6mm BR so accurate.

It was done many years ago with Remington brass but now that Lapua is making the brass there will probably be a resurgence of experimenting. Lapua makes the finest quality brass.
 
Acording to the article, expermentation has shown that the small primers are more consistent and this results in much lower ES/SD numbers. Something that is important for palma shooting (700 - 1000M). The small primers will also allow higher pressures, which will allow further japing of loads.

I am presuming the small primer has a correspondingly smaller flash hole. I cannot see this as being a problem, because the powder will ignite regardless.
 
Obtunded said:
I am presuming the small primer has a correspondingly smaller flash hole. I cannot see this as being a problem, because the powder will ignite regardless.
Click to expand...

I had to switch to small rifle magnum with the Remington (URBR?) small rifle brass to try and get reliable ignition anytime temps approached freezing. I still have some of those CCI small rifle magnum primers, but sold the brass. I tried a variety of powders, and they all had this problem in cold temps. Essentially the cold powder was quenching the primer. Nothing like having the rifle go off 1-2 seconds after the firing pin hits, or actually hearing the firing pin hit on each shot. Not fun or confidence inspiring. I was not alone in my experience.

I don't think Remington ever intended the brass to be shot as a full 308, and I can see why. It really was for experimentation or to be turned into BR sized cases.

Maybe Lapua has solved this problem with the shape or size of the flash hole?
 
cycbb486 said:
all it is, neck up to 6mm load and fireform. Do this twice and you have your 6XC brass ready to go. Then I would trim the cases do the desired length.

CBY
Click to expand...

Oh yeah thanks that clears it right up! ;)
Alright let me break it down more.How do you do either of those things?Case trimming I get.:D
 
LS, the 6XC was made from 22/250 brass by Mr. Tubbs originally. You run the brass through the FL sizer to establish the new shoulder. A light charge of pistol powder behind some cornmeal and pop, out comes a nearly formed case.

Case prep and after the first full pressure load, case is formed. He shows how to do this on his website and also on 6mmBR.com.

The 6XC is a nice case volume for getting the 115's moving at a decent speed. Improving the 22/250 case gives you the desired case volume. I made a 6 Mystic which was based off a 22/250 case and a 243AI reamer. Worked fine and gave the expected results.

Small rifle primers in 308 cases have been experimented many years ago. many became 22cal wildcats to get as much speed as possible. All died quickly because of hangfires.

Now a 308 will use much faster powders which may be easier to ignite. As they say, only one real way to find out but history of this concept doesn't bode well.

After being able to dial out vertical in this case volume in various cals, I don't see how a small rifle primer can make this process any better?

As for more pressure, many shooters are already well past magnum pressures and heading right into proof pressure loads. Going any higher IS a very real risk of damaging both steel and flesh. Remember that action steel degrades very rapidly when subjected to chamber pressures over 80,000psi.

I just recently helped someone set up for coyote popper using Lapua brass. The brass is one of the toughest I have worked with and was not easy to form. I would have had much better success with Win brass or even Rem as this stuff would have been much more ductile.

Lapua brass can take a beating but would not be my choice for wildcatting.

Jerry
 
The flash hole issue boggles me... a 6BR case is essentially a short 308 case with a sharper shoulder. At the base there is a .473" brass case with a small primer/flash hole and on one side is Varget, on the other a small primer. Never had powder fail to ignite in the cold (Or for any other reason than pilot error) and we shoot winter league in temps down to -20.

A 308 case is .473" at the base, and in this particular manifestation it will be a small primer and say... Varget. Why on earth will 30 grains of varget detonate, yet 47 wouldn't?

I an no engineer and no ballistician, but I have never taken apart a case and found half the powder burnt. It either ignites or it doesn't, and I cannot fathom how a small primer and flash hole would fail to ignite exactly the same powders as used with large primers and vice-versa.

As to primer size and pressure, that is a proven issue. In many high-pressure cases, the type of primer used dictates success or failure. The 6BR run near red-line needs a hard tough primer like a CCI. the 6.5X47 Lapua case was originally spec'd with a large primer and pressure related primer issues were an early criticism during "beta" testing and these were resolved by going to the small primer. I actually think it has more to do with flash hole size, but that is just a theory on my part.
 
Temp and type of powder (deterents, etc) have alot to do with how a primer effects ignition.

Again, this stuff was tried in the 70's and 80's. Didn't work well with their stuff.

Things have changed and there might not be any issues BUT...

I do know that CCI BR4 will not ignite my 223 load of Varget consistently when temps get cold. I must use a CCI 450 primer. We are only talking 23.7gr of powder and a powder column not much wider then that flash hole.

I understand the concept that once the powder right at the flash hole is ignited, it will continue to burn through the entire column. Then why am I experiencing this issue and only when it gets cold? Why did so many wildcatters run into problems decades ago?

Why even invent the LR primer? Or LR Magnum primer? Why is it recommended to use an even hotter/larger flash primer when loading for magnums or cases above 60gr's of powder?

Maybe some internal ballistics engineer can help us.

I fully agree that a SR primer will MASK pressure signs very well but it doesn't change the level of pressure reached. As I have climbed up on this soap box so many times, the issues is chamber pressure regardless of what fuel or ignition source.

Until someone can tell me that running proof pressure loads in their actions will not cause accelerated wear or failure, I will recommend that reloaders stay within published parameters.

This does not mean blackpowder pressures but certainly not much more then MAGNUM pressures (65,000psi). At magnum pressures, ALL reloading components/actions work just fine and have done so for decades.

It is only when the need to press into the stratosphere do we need bushed firing pins, vault tight actions, super strong brass, etc. The actions are still subjected to the pressure but there are little visual or physical cues to makes us soil our pants.

Chronographs a plenty. Pressure trace gear - not so much.

Having seen/own cases loaded specifically for proof pressure testing of factory rifles (Rems most likely), I can tell you there were no pressure signs on these cases and they would have ejected from the action without any fuss.

These cases are loaded specially for this purpose at 80 to 85000psi.

I am excited about the new gen of powders that should surface in the coming year or two. They are promoted to provide more ENERGY per gr of powder at the same peak pressure. Now that would give us a way to safely accelerate our bullets to faster speeds.

Since most matches are shot in warmer temps, maybe this will not pose a problem. But then gopher hunting doesn't happen often in the winter.

Only one way to find out....

Jerry
 
Obtunded said:
.........I an no engineer and no ballistician, but I have never taken apart a case and found half the powder burnt. It either ignites or it doesn't, and I cannot fathom how a small primer and flash hole would fail to ignite exactly the same powders as used with large primers and vice-versa............
Click to expand...

Here's what it looks like when H335 doesn't ignite properly in a 223 Ackley. Some powder is burnt, but many granules were left behind, discoloured, and some clumped together.

DSC05465.jpg


Not a sound from the rifle, other than the firing pin falling. Changed primers, and problem solved!

Ted
 
Obtunded said:
I have never taken apart a case and found half the powder burnt. It either ignites or it doesn't,
Click to expand...

When I was having those failures with the small rifle primer 308 cases I did take apart the rounds that didn't fire. Basically all the powder had clumped up together, almost a solid mass. You had to pick the chunks out of the case with a dental pick. This was throughout the case all the way to where the bullet sits on the powder. As I said earlier, essentially the flame from the primer was extinguished. The technical term for the primer flame is "brisance" and there just isn't enough of it to get a relatively large mass of cold powder hot enough to burn before the primer is spent.

There were several articles about this "back in the day". It is true, everything new in precision shooting has been done already!
 
Just remembered that there was a vendor (20 yrs ago?) who was selling primer sleeves so you could sit a sr primer in a lr primer pocket and essentially make any brass a small rifle primer brass. A few test were run and articles printed. If I recall correctly the results did not merit the efforts, and the primer sleeves quickly faded from memory.

Not say say Lapua's efforts won't succeed with this new brass in the Palma environment, just that it may not be practical to use the brass in all 308 applications.
 
rpollock said:
I had to switch to small rifle magnum with the Remington (URBR?) small rifle brass to try and get reliable ignition anytime temps approached freezing. I still have some of those CCI small rifle magnum primers, but sold the brass. I tried a variety of powders, and they all had this problem in cold temps. Essentially the cold powder was quenching the primer. Nothing like having the rifle go off 1-2 seconds after the firing pin hits, or actually hearing the firing pin hit on each shot. Not fun or confidence inspiring. I was not alone in my experience.

I don't think Remington ever intended the brass to be shot as a full 308, and I can see why. It really was for experimentation or to be turned into BR sized cases.
Maybe Lapua has solved this problem with the shape or size of the flash hole?
Click to expand...

So the whole point is to neck down to something a little ###ier than a 308?
 
Max Owner said:
So the whole point is to neck down to something a little ###ier than a 308?
Click to expand...

More like push the shoulder back, to get you in the 30-40 gr range. Remington knew this and made the brass rather thin walled specifically to allow easier case forming and less neck turning when the brass thickened up.

As I mentioned Lapua may have figured a way to deal with the hangfires by changing the shape or diameter of the flash hole. We will have to wait and see once the brass gets in the hands of reloaders.
 
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