I just got a model 52 Cooper 280AI Jackson Hunter. After measuring to see what I could load for a COAL; I found that I can't even load to mag length. I am wanting to shoot the 168 Berger classic hunter bullet. When loaded to mag length I would be .151" into the lands. I can only load to a COAL of 3.244" which is just right at the lands. Also the Redding dies are almost out of adjustment because we have to seat the bullet so deep into the case. I am at 57 gr of H4831sc and it will be compressed soon. Are all the Cooper 280AI chambered like this? Seems weird that they would offer a 1 in 9 twist and not chamber it for long heavy bullets. Any help is appreciated. Thanks.
You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an alternative browser.
You should upgrade or use an alternative browser.
Cooper 280AI Chamber question.
- Thread starter BEEMAN
- Start date
Help Support Long Range Hunting Forum
I just got a model 52 Cooper 280AI Jackson Hunter. After measuring to see what I could load for a COAL; I found that I can't even load to mag length. I am wanting to shoot the 168 Berger classic hunter bullet. When loaded to mag length I would be .151" into the lands. I can only load to a COAL of 3.244" which is just right at the lands. Also the Redding dies are almost out of adjustment because we have to seat the bullet so deep into the case. I am at 57 gr of H4831sc and it will be compressed soon. Are all the Cooper 280AI chambered like this? Seems weird that they would offer a 1 in 9 twist and not chamber it for long heavy bullets. Any help is appreciated. Thanks.
Take it to a gunsmith and have him touch the throat for you, so it will accept the longer bullets.
Good luck
436
Might have to I guess. Even if I could load it to mag length, it would be good. I think I am out of case capacity with this seating depth. Don't see how some guys are running up to 63 gr of Retumbo. I'd never fit that in my case.
With a 168gr and 63grs of Retumbo, perhaps a long drop tube was used.. I looked into Ackley's book #1 I see where he has a 140gr with 63gr of IMR 4350... and has he get's to the 175gr with the same powder it drops to 58grs so I'm thinking 63grs of Retumbo with a 168gr bullet would have to be a very compressed load! with the bullet(s) set "way" the hell out there.
436
Was hoping some other Cooper 280AI shooters would chime in. I used the search function here; and there was lots of loads listed. Still not sure how they are getting that much powder in their cases. They must have a different throat than my Cooper.
Ridgerunner665
Well-Known Member
- Joined
- Sep 15, 2008
- Messages
- 553
Retumbo is too slow for the Ackley....even with 180 grain bullets....the loads using it may be accurate, but they are slower than loads using faster powders.
IMR 7828ssc, MRP, and Reloder 22 are the ideal powders for the 280 Ackley...Reloder 25 is the absolute slowest powder that has any place in a 280 Ackley with a standard SAAMI throat....and Retumbo is too slow even with a long throat....a 28" barrel might make Retumbo worthwhile also.
That may upset some folks...but its true.
Get some 7828, MRP, or RL 22 and you'll have plenty of room...and just as much speed and accuracy, probably more even.
IMR 7828ssc, MRP, and Reloder 22 are the ideal powders for the 280 Ackley...Reloder 25 is the absolute slowest powder that has any place in a 280 Ackley with a standard SAAMI throat....and Retumbo is too slow even with a long throat....a 28" barrel might make Retumbo worthwhile also.
That may upset some folks...but its true.
Get some 7828, MRP, or RL 22 and you'll have plenty of room...and just as much speed and accuracy, probably more even.
Ridgerunner665
Well-Known Member
- Joined
- Sep 15, 2008
- Messages
- 553
The best powders are on the top...you'll notice, Retumbo is way down the list....EDIT: oops, thats 180 grain Bergers...will do 168's down below.
Code:
Cartridge : .280 Ack Imp Nosler brass
Bullet : .284, 180, Berger VLD G7 #28405
Useable Case Capaci: 61.933 grain H2O = 4.021 cm³
Cartridge O.A.L. L6: 3.244 inch = 82.40 mm
Barrel Length : 24.0 inch = 609.6 mm
Predicted Data for Indicated Charges of the Following Powders.
Matching Maximum Pressure: 64000 psi, or 441 MPa
or a maximum loading ratio or filling of 107 %
These calculations refer to your specified settings in QuickLOAD 'Cartridge Dimensions' window.
C A U T I O N : any load listed can result in a powder charge that falls below minimum suggested
loads or exceeds maximum suggested loads as presented in current handloading manuals. Understand
that all of the listed powders can be unsuitable for the given combination of cartridge, bullet
and gun. Actual load order can vary, depending upon lot-to-lot powder and component variations.
USE ONLY FOR COMPARISON !
63 loads produced a Loading Ratio below user-defined minimum of 90%. These powders have been skipped.
Powder type Filling/Loading Ratio Charge Charge Vel. Prop.Burnt P max P muzz B_Time
% Grains Gramm fps % psi psi ms
--------------------------------- -----------------------------------------------------------------
Vihtavuori N560 102.5 59.8 3.87 2877 99.3 64000 12547 1.212 ! Near Maximum !
Norma MRP 100.7 60.0 3.89 2876 100.0 64000 12085 1.218 ! Near Maximum !
Accurate MAGPRO 102.7 62.4 4.04 2872 98.5 64000 12683 1.218 ! Near Maximum !
IMR 7828 SSC 101.2 59.4 3.85 2866 99.6 64000 12112 1.203 ! Near Maximum !
IMR 7828 107.0 59.4 3.85 2866 99.6 64000 12112 1.203 ! Near Maximum !
ADI AR 2213 102.2 59.0 3.82 2852 99.5 64000 12028 1.201 ! Near Maximum !
Alliant Reloder-22 102.7 59.3 3.84 2851 99.9 64000 11985 1.219 ! Near Maximum !
Winchester WXR 105.5 59.6 3.86 2851 99.9 64000 12010 1.219 ! Near Maximum !
ADI AP 2214 106.1 62.9 4.08 2849 99.7 64000 11861 1.198 ! Near Maximum !
Ramshot Magnum 102.5 63.8 4.13 2835 100.0 64000 11417 1.212 ! Near Maximum !
Alliant Reloder-25 107.0 60.8 3.94 2832 100.0 60451 11548 1.238 ! Near Maximum !
ADI AR 2209 99.1 56.2 3.64 2810 99.9 64000 11360 1.210 ! Near Maximum !
Alliant Reloder-19 99.6 56.9 3.69 2808 99.9 64000 11427 1.218 ! Near Maximum !
Alliant Reloder-17 90.2 54.0 3.50 2803 100.0 64000 10627 1.223 ! Near Maximum !
Ramshot Hunter 95.1 56.1 3.63 2795 100.0 64000 10944 1.226 ! Near Maximum !
Hodgdon H4831 104.9 58.2 3.77 2789 99.0 64000 11364 1.215 ! Near Maximum !
Hodgdon H4831 SC 100.8 58.2 3.77 2789 99.0 64000 11364 1.215 ! Near Maximum !
Vihtavuori N570 107.0 64.4 4.17 2787 94.9 53594 13370 1.303
Norma 204 94.5 55.7 3.61 2785 99.8 64000 11140 1.219 ! Near Maximum !
Norma MRP 2 107.0 61.1 3.96 2774 99.1 55771 12285 1.296 ! Near Maximum !
Vihtavuori N550 92.0 53.7 3.48 2770 100.0 64000 10602 1.237 ! Near Maximum !
Norma URP 94.7 53.5 3.46 2769 100.0 64000 10458 1.233 ! Near Maximum !
Winchester Supreme 780 98.3 59.2 3.83 2765 99.8 64000 10876 1.224 ! Near Maximum !
Accurate 4350 93.7 53.5 3.47 2763 100.0 64000 10398 1.251 ! Near Maximum !
Alliant Reloder-33 107.0 67.1 4.35 2759 94.9 52606 13192 1.315
Vihtavuori N165 105.0 59.3 3.84 2758 100.0 64000 10633 1.229 ! Near Maximum !
Accurate 3100 102.8 58.7 3.80 2755 100.0 64000 10488 1.253 ! Near Maximum !
IMR 4831 99.3 54.3 3.52 2751 100.0 64000 10228 1.242 ! Near Maximum !
Hodgdon H4350 97.2 54.3 3.52 2746 100.0 64000 10473 1.224 ! Near Maximum !
Vihtavuori N160 105.2 57.6 3.73 2745 99.4 64000 10725 1.224 ! Near Maximum !
IMR 4350 95.4 54.2 3.51 2745 100.0 64000 10445 1.225 ! Near Maximum !
Hodgdon Hybrid 100V 97.1 53.6 3.48 2723 100.0 64000 9639 1.236 ! Near Maximum !
ADI AR 2217 107.0 60.4 3.92 2716 98.7 54728 11535 1.287
Hodgdon H1000 107.0 60.4 3.92 2716 98.7 54728 11535 1.287
ADI AR 2225 107.0 61.4 3.98 2674 99.7 47959 11964 1.368
Hodgdon Retumbo 107.0 61.4 3.98 2674 99.7 47959 11964 1.368
Vihtavuori N150 95.0 51.2 3.32 2661 100.0 64000 9128 1.249 ! Near Maximum !
ADI AR 2218 107.0 65.1 4.22 2650 91.8 47630 13021 1.367
Vihtavuori N135 91.2 47.2 3.06 2608 100.0 64000 8415 1.263 ! Near Maximum !
Vihtavuori 24N41 107.0 65.1 4.22 2607 86.9 50380 11558 1.345
Norma 217 107.0 60.2 3.90 2592 98.4 42475 12062 1.461
Vihtavuori N170 107.0 60.4 3.92 2571 92.0 50011 11002 1.381
Hodgdon H870 107.0 63.1 4.09 2569 93.2 42657 12216 1.454
Alliant Reloder-50 107.0 66.1 4.28 2533 89.7 40123 12490 1.510
Hodgdon US 869 107.0 65.1 4.22 2431 82.8 40931 10791 1.490
Hodgdon 50BMG 107.0 62.0 4.02 2429 78.6 41190 10751 1.485
Accurate 8700 107.0 63.7 4.13 2359 86.1 36829 10567 1.559
Vihtavuori 20N29 107.0 65.7 4.26 2337 82.7 35447 10628 1.591Ridgerunner665
Well-Known Member
- Joined
- Sep 15, 2008
- Messages
- 553
Code:
Cartridge : .280 Ack Imp Nosler brass
Bullet : .284, 168, Berger Hunt VLD G7 #28501
Useable Case Capaci: 63.212 grain H2O = 4.104 cm³
Cartridge O.A.L. L6: 3.244 inch = 82.40 mm
Barrel Length : 24.0 inch = 609.6 mm
Predicted Data for Indicated Charges of the Following Powders.
Matching Maximum Pressure: 64000 psi, or 441 MPa
or a maximum loading ratio or filling of 107 %
These calculations refer to your specified settings in QuickLOAD 'Cartridge Dimensions' window.
C A U T I O N : any load listed can result in a powder charge that falls below minimum suggested
loads or exceeds maximum suggested loads as presented in current handloading manuals. Understand
that all of the listed powders can be unsuitable for the given combination of cartridge, bullet
and gun. Actual load order can vary, depending upon lot-to-lot powder and component variations.
USE ONLY FOR COMPARISON !
57 loads produced a Loading Ratio below user-defined minimum of 90%. These powders have been skipped.
Powder type Filling/Loading Ratio Charge Charge Vel. Prop.Burnt P max P muzz B_Time
% Grains Gramm fps % psi psi ms
--------------------------------- -----------------------------------------------------------------
Norma MRP 101.8 61.9 4.01 2979 100.0 64000 12419 1.180 ! Near Maximum !
Vihtavuori N560 103.6 61.7 4.00 2977 98.9 64000 12830 1.175 ! Near Maximum !
Accurate MAGPRO 103.8 64.3 4.17 2969 97.9 64000 12935 1.181 ! Near Maximum !
IMR 7828 SSC 102.3 61.2 3.97 2965 99.2 64000 12396 1.165 ! Near Maximum !
Alliant Reloder-22 103.8 61.2 3.96 2952 99.8 64000 12290 1.181 ! Near Maximum !
Winchester WXR 106.6 61.5 3.98 2951 99.7 64000 12312 1.181 ! Near Maximum !
ADI AR 2213 103.3 60.8 3.94 2951 99.1 64000 12298 1.164 ! Near Maximum !
ADI AP 2214 107.0 64.7 4.19 2942 99.3 63745 12118 1.163 ! Near Maximum !
Ramshot Magnum 103.6 65.7 4.26 2934 100.0 64000 11714 1.173 ! Near Maximum !
IMR 7828 107.0 60.6 3.93 2933 99.0 61718 12315 1.184 ! Near Maximum !
Alliant Reloder-17 91.3 55.8 3.62 2910 100.0 64000 10928 1.184 ! Near Maximum !
ADI AR 2209 100.1 58.0 3.76 2910 99.7 64000 11646 1.172 ! Near Maximum !
Alliant Reloder-19 100.7 58.7 3.80 2908 99.7 64000 11714 1.180 ! Near Maximum !
Alliant Reloder-25 107.0 62.0 4.02 2902 100.0 58156 11813 1.220 ! Near Maximum !
Ramshot Hunter 96.2 57.9 3.75 2897 100.0 64000 11249 1.187 ! Near Maximum !
Hodgdon H414 90.8 56.0 3.63 2896 100.0 64000 11299 1.188 ! Near Maximum !
Winchester 760 90.8 56.0 3.63 2896 100.0 64000 11299 1.188 ! Near Maximum !
Hodgdon H4831 105.9 60.0 3.89 2885 98.6 64000 11604 1.177 ! Near Maximum !
Hodgdon H4831 SC 101.8 60.0 3.89 2885 98.6 64000 11604 1.177 ! Near Maximum !
Norma 204 95.5 57.5 3.72 2884 99.6 64000 11416 1.181 ! Near Maximum !
Vihtavuori N550 93.0 55.4 3.59 2873 100.0 64000 10897 1.198 ! Near Maximum !
Norma URP 95.7 55.2 3.57 2872 100.0 64000 10754 1.194 ! Near Maximum !
Accurate 4350 94.8 55.2 3.58 2867 100.0 64000 10700 1.211 ! Near Maximum !
Winchester Supreme 780 99.2 61.0 3.95 2862 99.6 64000 11134 1.185 ! Near Maximum !
Vihtavuori N165 106.1 61.2 3.96 2856 99.9 64000 10907 1.190 ! Near Maximum !
Accurate 3100 103.9 60.5 3.92 2855 100.0 64000 10778 1.214 ! Near Maximum !
IMR 4831 100.4 56.0 3.63 2854 100.0 64000 10517 1.203 ! Near Maximum !
Hodgdon H4350 98.2 56.0 3.63 2845 99.9 64000 10756 1.186 ! Near Maximum !
IMR 4350 96.4 55.9 3.62 2844 99.9 64000 10731 1.186 ! Near Maximum !
Vihtavuori N160 106.2 59.3 3.84 2841 99.0 64000 10965 1.185 ! Near Maximum !
Vihtavuori N570 107.0 65.7 4.26 2837 93.2 51474 13393 1.288
Norma MRP 2 107.0 62.4 4.04 2833 98.3 53427 12448 1.280
Hodgdon Hybrid 100V 98.2 55.4 3.59 2827 100.0 64000 9912 1.196 ! Near Maximum !
IMR 4007 SSC 90.5 53.5 3.47 2825 99.9 64000 10601 1.195 ! Near Maximum !
Alliant Reloder-33 107.0 68.5 4.44 2807 93.3 50521 13200 1.300
Hodgdon VARGET 90.2 50.9 3.30 2803 100.0 64000 9920 1.188 ! Near Maximum !
IMR 4064 90.6 49.9 3.23 2793 100.0 64000 9714 1.193 ! Near Maximum !
Accurate 2700 90.7 55.2 3.57 2780 99.9 64000 10029 1.199 ! Near Maximum !
Hodgdon H1000 107.0 61.7 4.00 2774 97.7 52810 11670 1.268
ADI AR 2217 107.0 61.7 4.00 2774 97.7 52810 11670 1.268
Vihtavuori N150 96.0 52.8 3.42 2763 100.0 64000 9376 1.208 ! Near Maximum !
Hodgdon Retumbo 107.0 62.7 4.06 2727 99.1 46185 12159 1.351
ADI AR 2225 107.0 62.7 4.06 2727 99.1 46185 12159 1.351
Vihtavuori N135 92.2 48.7 3.16 2711 100.0 64000 8657 1.221 ! Near Maximum !
ADI AR 2218 107.0 66.4 4.30 2689 89.5 45956 12917 1.351
Vihtavuori 24N41 107.0 66.4 4.30 2653 84.9 48662 11478 1.327
Norma 217 107.0 61.4 3.98 2637 97.2 40680 12174 1.446
Vihtavuori N170 107.0 61.7 4.00 2623 90.4 48222 11002 1.363
Hodgdon H870 107.0 64.4 4.17 2610 91.3 40985 12180 1.439
Alliant Reloder-50 107.0 67.4 4.37 2567 87.4 38314 12385 1.498
Hodgdon US 869 107.0 66.4 4.30 2470 80.6 39471 10667 1.472
Hodgdon 50BMG 107.0 63.3 4.10 2469 76.4 39728 10613 1.466
Accurate 8700 107.0 65.1 4.22 2393 83.7 35504 10437 1.538
Vihtavuori 20N29 107.0 67.1 4.35 2369 80.2 34093 10470 1.570stanley52
Well-Known Member
Might have to I guess. Even if I could load it to mag length, it would be good. I think I am out of case capacity with this seating depth. Don't see how some guys are running up to 63 gr of Retumbo. I'd never fit that in my case.
People use Retumbo and have highly compressed loads. Retumbo does give great velocities with my 280AI with 168gr bergers, but my redding comp seater doesn't like how compressed it is. I use 58.5gr H4831sc and it shoots lights out.
Just got finished shooting. Worked up to 58.5 gr of H4831sc seated at 19 thou off the lands. COAL of 3.225". Speeds were 2892, 2892 and 2879 fps. First two shots was a ragged hole and the third opened it up a bit. Probably need a better operator. Thanks for all the replies and nice charts Ridgerunner. Looks like I am right in there for speeds. My gun also has a 24" barrel. It wasn't showing any pressure signs, but I think I will stop there for now. Limited time and hunting season is just around the corner here in Manitoba. Thanks again for all the help.
