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Discussion Starter #1
Ok,

I am now starting the process of sitting down to research what I want to try with my loads for my .260 when I get it. There are several huge variables, and this will take some time, but I could really use some help. I know mel is developing a .260 load right now so I'm sure he has plenty of ideas. And in typical APK fashion, I am numbering everything!

1. Bullets- The higher weight bullets such as the 139+ gr. bullets have significantly highter BCs. But I realize that you can't put as much powder behind them. For example, here are some base stats I found......




Sierra-

120gr. HPBT - .421 @ 3100 fps and above
.409 between 3100 and 2800 fps
.403 between 2800 and 2000 fps
.417 @ 2000 fps and below

140gr. HPBT - .535 @ 2800 fps and above
.526 between 2800 and 2000 fps
.521 @ 2000 fps and below

142gr. HPBT - .595 @ 2850 fps and above
.580 between 2850 and 2400 fps
.575 between 2400 and 2050 fps
.550 @ 2050 and below

Hornaday-

140gr. A-Max Moly - .550

Lapua-

123gr. Scenar - .547

123gr. Scenar - .547
Silver Jacket

139gr. Scenar - .615

139gr. Scenar - .615
Silver Jacket


2. Powder- Heard lots of people saying that H4350 is the only way to go for the 6.5.



3. So........what do you guys think will make the best cartridge?

Btw- my platform will have a 26" barrel with a 1:8.5 twist.
 

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I think you are leaving off two important lapua bullets:

Lapua 108gr Scenar BC: .478
Lapua 144gr FMJBT BC: .636

I personally like the 123gr lapua and that is the focus of our LR load.

MEL
 

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Discussion Starter #3
ok thanks mel, I was conentrating on the 120-140 range because that is all I had heard of and I just threw up some idea, but thanks, I will have to check those out. How do I know what amount of powder I can fit in the case w/ a given bullet. And how do I know what muzzle velocity that will produce. My ballistics program asks for a muzzle velocity so I used 2900fps because that is what I had heard you mention before.
 

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From the Hodgdon web site:

46.5 grains of H4350 with a 120 grain Sierra soft point yields 2900 fps.

42.0 grains of H4350 with a 140 grain Sierra soft point yields 2670 fps.

( Overall length of both loads is 2.780")

If you use a 108 grain Lapua, I bet you could work up to 47 or 47.5 grains of H4350. But reduce the charge down to 44.5 or so grains, and slowly work your way up as pressure indications allow.

If you need a chronograph, I would lend you mine.

Mad
 

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The 108gr load that mad is talking about would be a 1000 yard gem. The 108 has a high enough BC to retain velocity well to 1000, and you can probably get 3100 fps. (a guess, no experience on that). You don't have much energy, but if you dinging gongs, it would be a good one. (i worked up some ideas with this bullet for the LR load, but have shied away from it because of the lack of energy on target)

after 1000 yards, it really dies quickly.

MEL
 

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Discussion Starter #6
1. Does the energy really matter to me if I am just killing paper?

2. And do I need a chronograph? never used one before?

3. How will I know what 'pressure indications allow?
 

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Pressure Indications: If you see flattened primers, that's a pressure indication. The edges of your fired primers should always be at least slightly rounded.

If your rifle experiences hard extraction, that's another pressure sign.

A chronograph is a handy tool to let you know your muzzle velocities. If you get velocities that are way beyond what's expected, that's another sign that pressures may be too high.

I will lend you my chronograph when you have a bunch of rounds loaded up. But you must promise to post the results here.

A chronograph is also very useful when it comes to measuring ballistic uniformity. Rounds that feature uniform velocities are usually the most accurate.

Mad
 

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Discussion Starter #9
Obviously there is a lack of options in brass when it comes to the .260. But I was just reading on ar15.com that you can 'neck up' .243 brass or 'neck down' 7/08 brass. I know the 260 is a necked down 308 cartridge, but how would you neck up the .243, im lost on this one.
 

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Would he just need a sizing die to use his loading press to neck up or down? not the same, but kinda like how a 45-70 casing needs to be belled out to accept the bullet?
 

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Discussion Starter #11
I called Redding, they said with a standard 260 Full Length die I can turn good .308 or .243 brass into 260. Should I do this and get good quality brass like Lapua, or get the Remingtion 260 brass?
 

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You would just run the .308 case through the .260 sizing die. But after necking down, you should check that the case is the right length and trim it if necessary.

Be advised that when you neck a case down, you have a different case capacity than a non-necked down case. So be careful, when developing loads.


Mad
 

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APK-223 said:
I called Redding, they said with a standard 260 Full Length die I can turn good .308 or .243 brass into 260. Should I do this and get good quality brass like Lapua, or get the Remingtion 260 brass?
I would get quality brass like Lapua if you want to get the best groups. Also I would recommend 243 brass insted of .308. .308 will work, but you may have to trim and turn the case mouths. Turning the neck is a little advanced if you havent reloaded before, not to mention a time consumng pain in the,..... well you know where.
 

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Discussion Starter #14
yea, I have been hearing that doing the 243 is the way to go. Does all this work really get me an advantage over the 260 Remington brass?
 

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APK-223 said:
yea, I have been hearing that doing the 243 is the way to go. Does all this work really get me an advantage over the 260 Remington brass?
Laupa brass is much more consistant than Remington. If Laupa made 260 brass I would say get theirs in 260. With the 243 brass all you need to do is run it through your sizer die when it is new then carry on as usual. After the first shooting no problem, just use it as you would 260 brass, it really isn't much more work and only when it is new. BTW 243=6mm so .5 mm is the diffrence. I am not sure if the shoulder slope etc is the same or not.

The diffrence between Laupa and Rem brass is huge. I used to shoot Rem brass and for tight groups I would weigh my cases for consistancy to within +- 5 gr ( I think) It would take at least 100 rem cases to get 25 for a match many times more. I finally kicked down for some Laupa. I started the process and guess what. They were all within my specs on weight. My groups shrank as well. It is the most consistant brass you will find. I am sure they have the occasional bad lot, but have never heard of it.

On the other hand if you are just hunting and looking for 2 MOA use the rem brass, it is cheaper.
 

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Discussion Starter #16
ok, the only bad part is i have to buy a new die, the comp. die wont work. But thanks for the input.
 

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Mad,

I believe that was the point though. The only people who make factory 260 brass is remington, which would not be nearly as good as lapua brass resized.

MEL
 
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