OK my .260 is Baaaaaaaaack...

[Afy]

Re-barrelled for free. Now have a 26 inch with a 1 in 8 twist.

Te maker has guaranteed:

0.24 MoA accuracy...

Gave me evidence of the group... 5 shots 1.121 inches at 300 meters

Load data:

42.1 grains of VV N550 with a 139 Lapua Scenar and an OAL of 2.925 inches.

Which accroding to OBT gives me a barrel time of 1.31ms close to node 5.

However QL is stating that this might be a dangerous load...

Cartridge : .260 Rem
Bullet : .264, 139, Lapua Scenar GB458 6018
Useable Case Capaci: 47.661 grain H2O = 3.095 cm³
Cartridge O.A.L. L6: 2.925 inch = 74.30 mm
Barrel Length : 26.0 inch = 660.4 mm
Powder : Vihtavuori N550

Predicted data by increasing and decreasing the given charge,
incremented in steps of 2.0% of nominal charge.
CAUTION: Figures exceed maximum and minimum recommended loads !

Step Fill. Charge Vel. Energy Pmax Pmuz Prop.Burnt B_Time
% % Grains fps ft.lbs psi psi % ms

-20.0 75 33.68 2291 1620 30093 7368 95.2 1.713
-18.0 77 34.52 2344 1696 32006 7566 96.1 1.672
-16.0 79 35.36 2397 1773 34035 7756 96.9 1.632
-14.0 81 36.21 2449 1851 36186 7935 97.6 1.593
-12.0 83 37.05 2501 1931 38465 8105 98.2 1.551
-10.0 84 37.89 2553 2012 40880 8263 98.7 1.507
-08.0 86 38.73 2604 2093 43439 8409 99.2 1.465
-06.0 88 39.57 2655 2176 46151 8544 99.5 1.425
-04.0 90 40.42 2706 2260 49027 8665 99.8 1.387
-02.0 92 41.26 2756 2345 52076 8774 99.9 1.349 ! Near Maximum !
+00.0 94 42.10 2806 2430 55310 8868 100.0 1.313 ! Near Maximum !
+02.0 96 42.94 2855 2516 58743 8952 100.0 1.279 ! Near Maximum !
+04.0 98 43.78 2904 2603 62388 9032 100.0 1.246 !DANGEROUS LOAD-DO NOT USE!
+06.0 99 44.63 2952 2690 66261 9111 100.0 1.213 !DANGEROUS LOAD-DO NOT USE!
+08.0 101 45.47 3000 2778 70379 9187 100.0 1.183 !DANGEROUS LOAD-DO NOT USE!
+10.0 103 46.31 3048 2867 74762 9260 100.0 1.153 !DANGEROUS LOAD-DO NOT USE!

Results caused by ± 10% powder lot-to-lot burning rate variation using nominal charge
Data for burning rate increased by 10% relative to nominal value:
+Ba 94 42.10 2906 2606 65831 8533 100.0 1.224 !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba 94 42.10 2657 2179 45002 8983 97.3 1.434


Anyhow... will verify on saturday... and see what happens.

 

[USSR]

However QL is stating that this might be a dangerous load...

Afy,

QuickLoad is only saying to use caution. A dangerous load in one rifle is a safe load in another.

Don

 

[NCsmitty]

I'm looking forward to your report. Good luck!

NCsmitty

 

[jerkface11]

I'm glad you got your rifle back. I'm looking forward to shooting against you in the next postal match. Oh did you find out what was wrong with the first barrel?

 

[Afy]

They messd up the rifling process or so it seems.

 

[R.W.Dale]

They messd up the rifling process or so it seems.

I still stand by my assertion that they goofed and used either a .277 or .284 bbl blank. Of course they'd never admit as much.

 

[Afy]

Entirely possble.

They begin the barrelling process by button rifiling the barrel.
The new one is cut rifled and is the first one they have done with an 8 twist in .260...

 

[EShell]

Good luck with your .260 Afy!

I'm shooting a custom M700 in .260 and for brass, I'm shooting Black Hills factory match ammo awhile. The BH is loaded into Rem cases with a 139 Scenar at 2,850 fps. It's delivering about 1/2 MOA for me with this ammo.

I also have a 6.5-284 Norma and a 6.5-300 Wby Mag and usually use Lapua 139s, Berger 140s and Sierra 142 in those rifles. IMHO, the .260 is going to happier with slightly lighter bullets.

I have some 123 Scenars that have shot extremely well as varmint bullets in my 6.5-300Wby (3,500 fps) and I plan to try them in the .260. I also have some Norma 130s, but accuracy with those thus far has been mediocre in two different barrels.

 

[Afy]

Went to the range today....

Not looking good...

 

[Bullet]

Went to the range today....

Not looking good...

More info?

 

[Afy]

http://www.thehighroad.org/showthread.php?t=384292