140gr Accubond and Retumbo.

[tyson22250]

wondering if any one has played with RETUMBO and 140gr Accubonds in the 7mm rem mag? Anyone have a quick load data?
Thanks

 

[MAinAR]

Yes and can tell you it's VMD (bulk density) makes it difficult to get enough in a case to be efficient with 140AB's. With my gun even with it having a 26" barrel it was always real low velocity with Retumbo plus I don't like compressed loads. Keep in mind that my gun seems to run a smooth 100fps slower than any load data I have ever compared. I went with the RL 26 which burn rate is only slighty faster than Retumbo if any, but with it being so much more dense it occupies much less space that Retumbo. Plus I got a lot of smoke with Retumbo loads with light bullets like this.

Retumbo at the Hodgdon max prescription of 75gr (105%) "compressed" occupies 5.41cc's of volume.

Where as the load that shot best for me with RL26 with Fed215GM was at 72grs (which is 0.8gr above Alliants listed max load so work up).......the RL26 at 72gr's occupies only 4.82cc's of volume. Loaded to OAL of 3.26 there is still a bit of "shake" space in the load. I am getting right at 3,200fps with this load and the 140AB but remember my barrel is on the slow side.......but super accurate from a Sendero.

 

[Mighty Peace]

Never tried it as I do not have 7mmRM, but I LOVE this powder with 140gr AB's in my 270WSM's rifles I have.

 

[MAinAR]

Never tried it as I do not have 7mmRM, but I LOVE this powder with 140gr AB's in my 270WSM's rifles I have.

Yes but the 270wsm can make much more pressure efficiently than the 7RM.

 

[Dwh7271]

Cartridge : 7 mm Rem. Mag.(SAAMI)
Bullet : .284, 140, Nosler AccuBond 59992
Useable Case Capaci: 74.204 grain H2O = 4.818 cm³
Cartridge O.A.L. L6: 3.290 inch = 83.57 mm
Barrel Length : 24.0 inch = 609.6 mm
Powder : Hodgdon Retumbo

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 83 56.93 2251 1575 22342 9431 80.9 1.727
-18.0 85 58.35 2314 1664 23803 9876 83.1 1.685
-16.0 87 59.77 2378 1758 25366 10315 85.1 1.643
-14.0 89 61.20 2443 1856 27042 10745 87.1 1.602
-12.0 91 62.62 2510 1959 28838 11163 89.0 1.562
-10.0 93 64.04 2578 2065 30764 11566 90.7 1.520
-08.0 95 65.47 2646 2176 32834 11949 92.4 1.481
-06.0 97 66.89 2715 2291 35057 12311 93.9 1.443
-04.0 99 68.31 2784 2410 37449 12648 95.3 1.404
-02.0 101 69.74 2854 2533 40023 12957 96.5 1.359
+00.0 103 71.16 2925 2659 42799 13235 97.5 1.315
+02.0 106 72.58 2995 2788 45794 13480 98.4 1.273
+04.0 108 74.01 3065 2920 49028 13688 99.1 1.232
+06.0 110 75.43 3135 3055 52529 13857 99.6 1.192 ! Near Maximum !
+08.0 112 76.85 3205 3193 56321 13987 99.9 1.154 ! Near Maximum !
+10.0 114 78.28 3274 3332 60437 14073 100.0 1.117 !DANGEROUS LOAD-DO NOT USE!

Results caused by ± 5% powder lot-to-lot burning rate variation using nominal charge
Data for burning rate increased by 5% relative to nominal value: