.270 WSM & RL 17

highcotton · Apr 13, 2011

Starting load development for a friends .270 WSM. Have RL 19, 17 & IMR 4350 to get started with. Nosler Manual 6 does not have loads listed for RL 17, however, according to the Alliant web page that powder is ideal for the "short magnums". Planning on pushing 140 gr bullets, probably BT's. Any advice on a starting point for RL 17 under a 140 gr bullet? I was kinda thinking about starting at 60 grains and moving up in 1/2 grain increments while watching for issues with pressure. Oh yeah, WIN brass and CCI primers.

DrMike · Apr 13, 2011

You're tickling the dragon's tail at 60 grains. It may work, but it will be a right at maximum or above.

Cartridge : .270 WSM
Bullet : .277, 140, Nosler BalTip 27140
Useable Case Capaci: 71.658 grain H2O = 4.653 cm³
Cartridge O.A.L. L6: 2.860 inch = 72.64 mm
Barrel Length : 24.0 inch = 609.6 mm
Powder : Alliant Reloder-17

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 69 47.60 2598 2098 34650 10156 98.7 1.490
-18.0 70 48.79 2654 2190 36830 10379 99.2 1.455
-16.0 72 49.98 2710 2283 39136 10583 99.5 1.414
-14.0 74 51.17 2765 2377 41577 10769 99.8 1.375
-12.0 76 52.36 2820 2473 44158 10935 100.0 1.336
-10.0 77 53.55 2874 2568 46887 11082 100.0 1.300
-08.0 79 54.74 2928 2665 49778 11220 100.0 1.265
-06.0 81 55.93 2981 2762 52836 11356 100.0 1.231
-04.0 82 57.12 3033 2859 56050 11489 100.0 1.199 ! Near Maximum !
-02.0 84 58.31 3084 2957 59429 11620 100.0 1.168 ! Near Maximum !
+00.0 86 59.50 3135 3055 62995 11748 100.0 1.137 ! Near Maximum !
+02.0 88 60.69 3186 3155 66759 11874 100.0 1.109 !DANGEROUS LOAD-DO NOT USE!
+04.0 89 61.88 3236 3254 70734 11996 100.0 1.081 !DANGEROUS LOAD-DO NOT USE!
+06.0 91 63.07 3285 3355 74934 12116 100.0 1.054 !DANGEROUS LOAD-DO NOT USE!
+08.0 93 64.26 3335 3457 79373 12232 100.0 1.028 !DANGEROUS LOAD-DO NOT USE!
+10.0 94 65.45 3384 3559 84067 12346 100.0 1.004 !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 86 59.50 3222 3228 73863 11426 100.0 1.066 !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba 86 59.50 3003 2804 52081 12182 99.8 1.233

You'll get similar ballistics with the AB, and at the velocities you are generating, it will serve you better on impact.

Cartridge : .270 WSM
Bullet : .277, 140, Nosler AccuBond 54765
Useable Case Capaci: 71.442 grain H2O = 4.639 cm³
Cartridge O.A.L. L6: 2.860 inch = 72.64 mm
Barrel Length : 24.0 inch = 609.6 mm
Powder : Alliant Reloder-17

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 69 47.60 2601 2103 34800 10150 98.7 1.487
-18.0 71 48.79 2658 2196 36997 10371 99.2 1.453
-16.0 72 49.98 2714 2290 39318 10574 99.6 1.411
-14.0 74 51.17 2769 2384 41774 10759 99.8 1.372
-12.0 76 52.36 2824 2480 44374 10923 100.0 1.333
-10.0 78 53.55 2878 2576 47123 11068 100.0 1.297
-08.0 79 54.74 2932 2672 50033 11206 100.0 1.262
-06.0 81 55.93 2985 2769 53114 11342 100.0 1.228
-04.0 83 57.12 3037 2867 56353 11475 100.0 1.196 ! Near Maximum !
-02.0 84 58.31 3088 2965 59759 11605 100.0 1.165 ! Near Maximum !
+00.0 86 59.50 3139 3064 63354 11732 100.0 1.135 ! Near Maximum !
+02.0 88 60.69 3190 3163 67150 11857 100.0 1.106 !DANGEROUS LOAD-DO NOT USE!
+04.0 90 61.88 3240 3264 71160 11979 100.0 1.078 !DANGEROUS LOAD-DO NOT USE!
+06.0 91 63.07 3290 3364 75397 12098 100.0 1.051 !DANGEROUS LOAD-DO NOT USE!
+08.0 93 64.26 3339 3466 79877 12214 100.0 1.026 !DANGEROUS LOAD-DO NOT USE!
+10.0 95 65.45 3388 3569 84617 12327 100.0 1.001 !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 86 59.50 3227 3236 74292 11411 100.0 1.064 !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba 86 59.50 3008 2812 52373 12168 99.8 1.230

SJB358 · Apr 13, 2011

Looking at QL, it really doesn't look like RL17 would be great for the 140's. I know 3100 is pretty quick, but I can just about duplicate those speeds with the 150gr PT and BT using RL22. I know they say RL17 is a Short Mag powder, but those speeds don't look all that impressive.

Mike, I know you have some excellent accuracy out of it with the 130gr ET's and good speed, so I won't put my foot in my mouth, but it seems like RL17 is much more suited to the 300WSM than the 270WSM, as far as reaching what the cartridge is capable of. Seems like IMR7828, RL22 and the like are really making the 270WSM shine, at least with the heavier for caliber bullets. Scotty

DrMike · Apr 13, 2011

RL17 would not be my first choice in this instance; I'd look at other powders. However, highcotton specifically asked about that powder as he had information on the other two powders he had.

SJB358 · Apr 13, 2011

I got it Mike. I knew you were being the excellent QL runner! Again, there isn't anything that will take too many of the 140gr AB's at 3100. Not any animals I have ran across yet! Scotty

highcotton · Apr 14, 2011

Thanks for the QL info Doc. I'll skip the RL 17 and work with the IMR 4350 and RL 19- if I don't get acceptable accuracy out of the load development there I'll be requesting help!