156 EOL at 3100 FPS

Hespco said:

MY Win 70 264 mag EW 26" Bbl will easily drive the Nosler 140 AB to 3222 fps using VV24N41 powder. With a 156 gr bullet a yet slower burning powder like US 869 should do the 3100 fps with ease. These powders ( VV24N41 & US 869 ) are far slower than Rel 26 yet seem to be over looked.

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Isn't US869 extremely temperature UNstable?

Mike from Texas said:

I used to be the same way until I figured out it is a 264 WM with the radiused shoulder.

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5 more grains of powder and a far superior Neck is a difference some might consider appealing. Of course my planned build uses an "Ackley" shoulder & .320 Neck, I know he said No Cats. The OP dealing with a Governmental agency that requires a special permit for each and every gun. Something we don't have to tolerate here in the 28th.

MerlinMc said:

My 26 Nosler barrels are 8 twist and work great for 140 and 142 projectiles. 9 is too slow. 7.5 might be a good compromise if you ever wanted to shoot lighter projectiles.

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berger updated their twist calculator. 1:8" is sufficient for the 156.

Punisher said:

berger updated their twist calculator. 1:8" is sufficient for the 156.

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At sea level under 60ish degrees it is still only marginal with an 8 twist at 3000-3100 fps or so. He stated he hunts at low elevation in cold temps at times, so an 8 twist would not be a wise choice. A 7-7.5 twist is optimum, 8 twist will work if you hunt at higher elevations. I use an 8 twist in one of my rifles for them, but the lowest elevation I hunt is around 6500 ft. If your building a rifle for a specific bullet, no point to start out only marginal.

I was screwing around last night, I seated a 156 in a necked down 7mag(264wm) and also took a 7lrm case, necked(&turned) it down and seated a 156. The bullet bearing is well above the neck/shoulder junction in the LRM case, and just at the neck/shoulder in the 264wm case. I'd really like to build a 6.5 LRM!

highdrum said:

I was screwing around last night, I seated a 156 in a necked down 7mag(264wm) and also took a 7lrm case, necked(&turned) it down and seated a 156. The bullet bearing is well above the neck/shoulder junction in the LRM case, and just at the neck/shoulder in the 264wm case. I'd really like to build a 6.5 LRM!

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That is a dang good looking cartridge. Now if ADG made brass for it like they do 7mm rm......

I hope those 153 Atips work out on game. AB claims a G7 of .373

Ed AO said:

I hope those 153 Atips work out on game. AB claims a G7 of .373

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I did see AB just added that to their library, pretty impressive!! If I can see a high number of good terminal performance reports, I may try them out.....

did you see the 190 Atips? Hornrandy says .422 G7. I'm hoping for good terminal perform as well.

Chiming in here. I know its overbore but Im running a 6.5x300 WBY with a 156 @ 3150 with not a lot of pressure. 38 min @ 1600 yds was pretty satisfying.

Mazdayasna said:

5 more grains of powder and a far superior Neck is a difference some might consider appealing. Of course my planned build uses an "Ackley" shoulder & .320 Neck, I know he said No Cats. The OP dealing with a Governmental agency that requires a special permit for each and every gun. Something we don't have to tolerate here in the 28th.

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Ok so you have my attention. I have a 257 Wby and it's a screamer. I used to want a 6.5/257 but kind of lost interest a while back. Now I'm thinking about it again. I have a 28" Proof 8 twist blank begging to have something built.

codyadams said:

At sea level under 60ish degrees it is still only marginal with an 8 twist at 3000-3100 fps or so. He stated he hunts at low elevation in cold temps at times, so an 8 twist would not be a wise choice. A 7-7.5 twist is optimum, 8 twist will work if you hunt at higher elevations. I use an 8 twist in one of my rifles for them, but the lowest elevation I hunt is around 6500 ft. If your building a rifle for a specific bullet, no point to start out only marginal.

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Berger just updated their calculator for this in the past few months.
At slow velocities, they said that that it would be marginally stable, but over 3000 fps of muzzle velocity, I don't think you will notice "marginal" conditions. This lead them to update the suggested twist for most of their 6.5mm line.

I am shooting a 1:8" twist with the 156 EOL and it's 1/4moa at 100 yards and I generally shoot between 1/4 and 1/2 moa at long ranges out to 1400. I live at 1000 fas.

codyadams said:

That is a dang good looking cartridge. Now if ADG made brass for it like they do 7mm rm......

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codyadams said:

That is a dang good looking cartridge. Now if ADG made brass for it like they do 7mm rm......

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Gunwerks is to have adg manufactured 7lrm brass in April. There's a good chance I'll have a 6.5 ans 7mm running by summer.

Punisher said:

I am shooting a 1:8" twist with the 156 EOL and it's 1/4moa at 100 yards and I generally shoot between 1/4 and 1/2 moa at long ranges out to 1400. I live at 1000 fas.

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My 6.5 saum has a 24" 1:8 Proof and the 156's at 3070fps have been stable for me and shoot very very well. My AO is about 450 fas and I've seen no issues out to 1200yds