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260AI "Palma" brass v 260 Lapua brass

I have had good success with slower powder and longer barrels in my 260 and 260AI. Get the speed I want with lower pressure. Have I crossed reference with Quickload? No but brass lasts a lot longer versus using faster powders.
I am just hesitant to use the palma brass with slower powders for fear of ignition issues with them. I am talking H1000 area. They would probably be fine with magnum primers in warm weather but I don't always shoot in warm weather.
 
Why is more powder a good thing here?
Do you not have enough capacity from improved Lapua 260 brass?

That's the question I have; just because there is more room in the case it seems the pressure maximums are still relevant in the equation. Just because the case may stand up to more powder/pressure seems the barrel throat is going to be toast a lot sooner under the increased pressure or am I reading this wrong?
I'm just trying to figure out the benefits of all the work involved in re forming the 308 brass.
 
It's my view that the 260AI represents the perfect capacity for best in 26cal bullets(~140gr).
I don't have that capacity stored on this particular laptop. And there does not seem a lot of chatter about Lapua 260 brass.
So I wonder if there is some issue with Lapua 260 brass. Is the ~2950-3000fps node not being reached with it? Is this with barrels at least 26" long?
If this node IS being reached with it then more capacity would only be a detriment.
 
That's the question I have; just because there is more room in the case it seems the pressure maximums are still relevant in the equation. Just because the case may stand up to more powder/pressure seems the barrel throat is going to be toast a lot sooner under the increased pressure or am I reading this wrong?
I'm just trying to figure out the benefits of all the work involved in re forming the 308 brass.
Hello Wes. I think your question is very relevant. AND you are reading it correctly. If you were to use the strength of the Palma brass in order to run up the pressures, your barrel life will most definitely suffer, compared to "normal" pressures. I am just now almost ready to start load development in earnest with the Palma brass. However, my goal is NOT to run 3000 f.p.s. with 140 VLD's or the 140 LRBT, it is to run 2930"ish" with LESS E.S.s and lower S.D.s so that LONG shot strings may have a better chance of keeping a low vertical dispersion under the stress of a 20+ shot string. If it works, GREAT. However, if it does not, I still have the strongest brass around to shoot many, many loadings with.
 
It's my view that the 260AI represents the perfect capacity for best in 26cal bullets(~140gr).
I don't have that capacity stored on this particular laptop. And there does not seem a lot of chatter about Lapua 260 brass.
So I wonder if there is some issue with Lapua 260 brass. Is the ~2950-3000fps node not being reached with it? Is this with barrels at least 26" long?
If this node IS being reached with it then more capacity would only be a detriment.

I know I 'm reaching 2950-3000 with the Fireformed Lapua 260 brass but having said that, it is showing pressure, i.e., flattened primers. I will test some of both tomorrow running near those speeds with the 140 Berger Long Range Boatail.
 
Hello Wes. I think your question is very relevant. AND you are reading it correctly. If you were to use the strength of the Palma brass in order to run up the pressures, your barrel life will most definitely suffer, compared to "normal" pressures. I am just now almost ready to start load development in earnest with the Palma brass. However, my goal is NOT to run 3000 f.p.s. with 140 VLD's or the 140 LRBT, it is to run 2930"ish" with LESS E.S.s and lower S.D.s so that LONG shot strings may have a better chance of keeping a low vertical dispersion under the stress of a 20+ shot string. If it works, GREAT. However, if it does not, I still have the strongest brass around to shoot many, many loadings with.

Hey Ben sounds like you and I are seeking the same goals. In my first 260AI I found a really accurate node with the 140 LRBT's at 2880ish and the 260 Lapua brass fire formed but when the temps here in the south go from 55 degrees on the first relay to 95+ on the third it can have adverse effects on accuracy. Hope the accuracy holds up with the Palma brass.
 
Why is more powder a good thing here?
Do you not have enough capacity from improved Lapua 260 brass?

Greater capacity means that you can hit the same velocity/accuracy node but at a lower case pressure than the case with smaller capacity. Lower pressure loads are generally good for brass life and barrel life.

Larger case capacity would also be less sensitive to variations in powder charge weight from case to case, since a fixed amount of variation would be a smaller percentage amount of the total charge.
 
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I know I 'm reaching 2950-3000 with the Fireformed Lapua 260 brass but having said that, it is showing pressure, i.e., flattened primers. I will test some of both tomorrow running near those speeds with the 140 Berger Long Range Boatail.

That's the velocity I want, just lower pressure.
 
That's the velocity I want, just lower pressure.
This is exactly it. If you can hit 2900 with a straight 260 but ragged edge of pressure signs then an AI version should I. Theory be able to hit the same speed with less pressure. Or same speed with same pressure in a short barrel. My last 260 was a 27" barrel and at its peak was running almost exactly 2900. If I could go to a 24 and get the same speed without being over pressure then that a win for me.
 
I think the standard 260 case in Lapua has about the perfect case capacity when blown out to AI. This has been my experience anyway. Only complaint is that 260 brass costs a lot more than 243 and 308 brass that I used to make it from!

I still haven't found a better powder than R17 in the 260 AI.
 
Possibly H4350 is a mite slow to be well lit by SR primers with that case capacity. I've never used anything slower than Varget with similar case capacity calibres, but of course, translating from one to the other ain't exact science.

I bet this is it. H4350 is gonna be hard to ignite with small primers. It ain't Varget.
 
I use 4350 with CCI 450 with no problems shot in February at 600 yd shot 1.7 in best target up too 3.2 avg 2.6 you can run palma brass hard without pressure 1.5 gr more then large thats my 2 cents
 
I bet this is it. H4350 is gonna be hard to ignite with small primers. It ain't Varget.

I just ordered some RL 16 to see if this new powder will be a little faster in velocity in the "Palma" brass with less pressure than the H 4350.
The problem for some of us shooting F class strings of twenty-two rounds is temp related either from barrels heating up while trying to get rounds on target under similar conditions quickly or ambient temps changing dramatically from cooler to hot during the match or often times here in the south; both.
 
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Hello Wes. I think your question is very relevant. AND you are reading it correctly. If you were to use the strength of the Palma brass in order to run up the pressures, your barrel life will most definitely suffer, compared to "normal" pressures. I am just now almost ready to start load development in earnest with the Palma brass. However, my goal is NOT to run 3000 f.p.s. with 140 VLD's or the 140 LRBT, it is to run 2930"ish" with LESS E.S.s and lower S.D.s so that LONG shot strings may have a better chance of keeping a low vertical dispersion under the stress of a 20+ shot string. If it works, GREAT. However, if it does not, I still have the strongest brass around to shoot many, many loadings with.
Palma brass is the way to go with the 260AI. 2930fps keep brass annealed and shoot the same hundred brass for several barrels.:)
 
Put some MRP into them . The conversation will change .
Larry
On the 5th of this month I was doing some load development with my new 260AI. I use the Lapua Palma brass, Berger 140 hybrids, BR-4 primers with H-4831sc. The rifle has a 30" Bartlein, 8 twist. For some reason it runs ~100 fps slower than other barrels, and today I verified this with my friends Robert's rifle. We have the same chamber so I used two of his rounds in my rifle and I got 96 fps slower results (2,975). Here is some info:
Capture.JPG

I ended up with 48.8 grains of H-4831sc.

Joe
 
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