US869 in 7mm RM

[jimbires]

this is + 0.045

Cartridge : 7 mm Rem. Mag.(SAAMI)
Bullet : .284, 180, Berger Hy Tgt G7 #28407
Useable Case Capaci: 71.657 grain H2O = 4.653 cm³
Cartridge O.A.L. L6: 3.335 inch = 84.71 mm
Barrel Length : 26.0 inch = 660.4 mm
Powder : Hodgdon US 869

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 90 63.60 2218 1966 28090 9298 77.7 1.845
-18.0 93 65.19 2283 2084 30223 9689 79.5 1.792
-16.0 95 66.78 2350 2208 32542 10077 81.3 1.740
-14.0 97 68.37 2418 2337 35067 10459 83.1 1.689
-12.0 99 69.96 2487 2472 37822 10835 84.8 1.635
-10.0 102 71.55 2557 2613 40829 11202 86.4 1.575
-08.0 104 73.14 2628 2759 44120 11557 88.0 1.518
-06.0 106 74.73 2699 2912 47731 11900 89.5 1.463
-04.0 108 76.32 2772 3071 51701 12227 90.9 1.409
-02.0 111 77.91 2845 3236 56074 12536 92.2 1.358 ! Near Maximum !
+00.0 113 79.50 2920 3407 60907 12825 93.5 1.307 !DANGEROUS LOAD-DO NOT USE!
+02.0 115 81.09 2995 3585 66263 13092 94.7 1.259 !DANGEROUS LOAD-DO NOT USE!
+04.0 117 82.68 3071 3770 72220 13333 95.7 1.211 !DANGEROUS LOAD-DO NOT USE!
+06.0 120 84.27 3148 3961 78830 13546 96.7 1.166 !DANGEROUS LOAD-DO NOT USE!
+08.0 122 85.86 3226 4159 86201 13728 97.6 1.121 !DANGEROUS LOAD-DO NOT USE!
+10.0 124 87.45 3304 4364 94468 13876 98.3 1.078 !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 113 79.50 3108 3860 75721 13087 98.7 1.194 !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba 113 79.50 2683 2878 48065 11860 84.1 1.453

 

[jimbires]

this is +.165



Cartridge : 7 mm Rem. Mag.(SAAMI)
Bullet : .284, 180, Berger Hy Tgt G7 #28407
Useable Case Capaci: 73.577 grain H2O = 4.777 cm³
Cartridge O.A.L. L6: 3.455 inch = 87.76 mm
Barrel Length : 26.0 inch = 660.4 mm
Powder : Hodgdon US 869

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 90 64.80 2232 1991 28320 9564 78.3 1.839
-18.0 92 66.42 2298 2110 30465 9964 80.1 1.787
-16.0 94 68.04 2365 2235 32796 10360 81.9 1.735
-14.0 96 69.66 2433 2365 35332 10751 83.6 1.685
-12.0 99 71.28 2501 2501 38096 11134 85.3 1.629
-10.0 101 72.90 2571 2643 41111 11508 86.9 1.571
-08.0 103 74.52 2642 2790 44409 11870 88.4 1.514
-06.0 105 76.14 2714 2944 48023 12218 89.9 1.460
-04.0 108 77.76 2786 3103 51989 12551 91.3 1.406 ! Near Maximum !
-02.0 110 79.38 2860 3268 56355 12865 92.6 1.355 ! Near Maximum !
+00.0 112 81.00 2934 3440 61171 13159 93.9 1.305 !DANGEROUS LOAD-DO NOT USE!
+02.0 114 82.62 3009 3618 66502 13429 95.0 1.257 !DANGEROUS LOAD-DO NOT USE!
+04.0 117 84.24 3085 3803 72379 13673 96.0 1.210 !DANGEROUS LOAD-DO NOT USE!
+06.0 119 85.86 3161 3994 78889 13889 97.0 1.165 !DANGEROUS LOAD-DO NOT USE!
+08.0 121 87.48 3238 4191 86137 14073 97.8 1.121 !DANGEROUS LOAD-DO NOT USE!
+10.0 123 89.10 3316 4396 94241 14223 98.5 1.078 !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 112 81.00 3120 3891 75889 13400 98.9 1.192 !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba 112 81.00 2698 2910 48209 12194 84.6 1.450

 

[jimbires]

this is +.165 with the weighting factor changed to help with an overbore cartridge .

still using the default case water capacity . this can change outputs significantly .



Cartridge : 7 mm Rem. Mag.(SAAMI)
Bullet : .284, 180, Berger Hy Tgt G7 #28407
Useable Case Capaci: 73.577 grain H2O = 4.777 cm³
Cartridge O.A.L. L6: 3.455 inch = 87.76 mm
Barrel Length : 26.0 inch = 660.4 mm
Powder : Hodgdon US 869

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 91 65.44 2262 2045 28239 9838 77.3 1.812
-18.0 93 67.08 2329 2169 30371 10258 79.1 1.760
-16.0 95 68.71 2398 2298 32689 10676 80.9 1.709
-14.0 97 70.35 2468 2434 35210 11090 82.6 1.658
-12.0 100 71.98 2539 2576 37959 11498 84.3 1.603
-10.0 102 73.62 2611 2724 40961 11897 85.9 1.546
-08.0 104 75.26 2684 2879 44245 12285 87.5 1.489
-06.0 106 76.89 2758 3040 47846 12661 89.0 1.435
-04.0 109 78.53 2833 3208 51799 13022 90.4 1.382
-02.0 111 80.16 2909 3383 56162 13365 91.8 1.330 ! Near Maximum !
+00.0 113 81.80 2986 3564 60978 13688 93.1 1.281 !DANGEROUS LOAD-DO NOT USE!
+02.0 115 83.44 3064 3753 66317 13988 94.3 1.233 !DANGEROUS LOAD-DO NOT USE!
+04.0 118 85.07 3144 3950 72251 14262 95.4 1.186 !DANGEROUS LOAD-DO NOT USE!
+06.0 120 86.71 3224 4154 78852 14507 96.4 1.141 !DANGEROUS LOAD-DO NOT USE!
+08.0 122 88.34 3305 4365 86209 14721 97.2 1.096 !DANGEROUS LOAD-DO NOT USE!
+10.0 125 89.98 3387 4585 94462 14899 98.0 1.054 !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 113 81.80 3181 4045 75839 14014 98.5 1.169 !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba 113 81.80 2742 3005 48132 12614 83.5 1.424

 

[Joec7651]

Ok, now that winter is on the way out I’ll be picking this back up. The last Magnetospeed numbers was an average of 2850’ish shooting 180gr Berger hybrids from a 24” barrel, while still having room for 2.1 grains more powder In the case. There were no pressure signs. I’m thinking I’ll run out of room before primers flatten or I get sticky extraction. I didn’t shoot for Groups but the last load was about 1.25”. I’m going to creep up with the last 2.1 grains of 869. I’m also going to see what they do from the 26” X-caliber barrel.

 

[Joec7651]

Ok, I tried to go off of memory and it bit me in the keester. I ought to know better. Lol. After pulling my load book out it’s running at 2800 even out of the 24” barrelled 7RM. Wishful thinking or Hillbilly optimism On my part. Take your pick. That’s still not bad for a less than max load, 180gr Berger, and such a slow powder. I still have work to do with it and and my 26” 7RM.

 

[Alex36]

Thanks Jim, I really appreciate you taking the time to run it through Quickload. I’m not sure if I’ll be able to get to 2800 or not, but I think I’ll be able to get close. As far as magazine length I can seat them to 3.390” and have .010” left for small variations. So I can seat somewhat longer than SAAMI length.

Which brings me to a question……..some people see a 195gr bullet from a 7mm Rem Mag at 2800 fps and ask why settle for such a slow round. A slow Laod?! It’s a 200 grain bullet at 2800 fps! That’s what a 300 H&H will do with a 200gr load. If a 180gr bullet at 2700 fps from a 30-06 is enough for elk and moose, why is an essentially 200gr bullet(with much better SD and BC) scoffed at from a 7RM at 2800 fps. Has long range magnumitis made people so daft as they actually believe the BS? LOL.

Anyway, again Jim thank you very much. I’ll just have to see what it will do. The barrel seems to be on the fast side velocity wise so we will se.

You hit the Nail on the head! I do own a 28 nosler and shoot the 195s. But I started building that rifle in 2015. I’d like to think I decided on that before it became a fad Current usage canyon to canyon at the Oregon coast (I’ve got a few spots that black tail bucks walk out into just about daily, rough yardage 700 give or take where they show up ) maybe once a year I go and put that 195 to use on them . I do 90 percent of my hunting down here with a 6 pound 300 short mag and 180 grain sierra pro hunter. I love the 160 AccuBond out of my 7mags also. But typically use those if I draw over east. (Every few years). The elk at the coast are up close and personal so I love the 300wsm for that. But to your point of the 7 mag only pushing a monster 195 at 2800 getting scoffed at made laugh out loud! Your exactly right it’s ridiculous! That’s a lighting bolt on any game animal out to 750 easy But you’ve got the cutting edge out there and can’t talk them out of it. I guess to sum up what Im meaning is Iike my 28n but it’s heavy and cost a lot to play with it. I absolutely love every 7mag I’ve ever owned and will always use them more than any other caliber and if I build another custom it will be chambered in 7rem mag.

I bet with the right powder , reamer, barrel length you could send those 195 s at 2880 or even touch 2900. Which unlike my 28 (throated long for the 195). The saami chambered 28 n guys are typically in the mid to high 2900s with that slug.

 

[Joec7651]

Alex first, welcome to our forum! I love my 7mm RM’s. They do well. The 195’s wouldn’t work with the throats in the 2 I have, so I‘m working with the 180gr Hybrid right now. I’m not at maximum pressure in either rifle yet, so I’ve still got some testing to do. So far I’m getting 2800 fps from the 24” barrel and from the 26” I’m getting 2882 fps from the same load. I will see what I get before pressure signs start showing. Neither is a slouch with the 180’s where they are with the US869, and I get better velocity with RL25. They‘ll more than work on anything I’ll hunt. I want to see how far I can get them to group.