MRP load data for 280ai
- Thread starter muzz
- Start date
DrMike
Ballistician
- Nov 8, 2006
- 37,542
- 6,617
Cartridge : .280 Ack Imp
Bullet : .284, 140, Nosler AccuBond 59992
Useable Case Capaci: 66.211 grain H2O = 4.299 cm³
Cartridge O.A.L. L6: 3.330 inch = 84.58 mm
Barrel Length : 24.0 inch = 609.6 mm
Powder : Norma MRP
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 84 53.44 2545 2014 31028 10490 90.1 1.500
-18.0 86 54.78 2615 2126 33289 10848 91.6 1.460
-16.0 88 56.11 2685 2241 35727 11191 93.0 1.420
-14.0 90 57.45 2755 2360 38359 11517 94.3 1.376
-12.0 92 58.78 2826 2483 41197 11823 95.4 1.330
-10.0 94 60.12 2897 2609 44270 12108 96.5 1.286
-08.0 96 61.46 2968 2738 47595 12370 97.4 1.243
-06.0 99 62.79 3038 2870 51197 12606 98.2 1.202
-04.0 101 64.13 3109 3005 55105 12815 98.8 1.162
-02.0 103 65.46 3179 3142 59350 12995 99.3 1.123 ! Near Maximum !
+00.0 105 66.80 3250 3283 63969 13144 99.7 1.086 ! Near Maximum !
+02.0 107 68.14 3319 3425 69004 13261 99.9 1.051 !DANGEROUS LOAD-DO NOT USE!
+04.0 109 69.47 3389 3569 74457 13344 100.0 1.016 !DANGEROUS LOAD-DO NOT USE!
+06.0 111 70.81 3457 3716 80382 13407 100.0 0.983 !DANGEROUS LOAD-DO NOT USE!
+08.0 113 72.14 3526 3864 86838 13465 100.0 0.951 !DANGEROUS LOAD-DO NOT USE!
+10.0 115 73.48 3594 4015 93890 13516 100.0 0.920 !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 105 66.80 3403 3600 79165 12608 100.0 0.997 !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba 105 66.80 3026 2847 50459 12993 94.7 1.203
Cartridge : .280 Ack Imp
Bullet : .284, 160, Nosler AccuBond 54932
Useable Case Capaci: 64.303 grain H2O = 4.175 cm³
Cartridge O.A.L. L6: 3.330 inch = 84.58 mm
Barrel Length : 24.0 inch = 609.6 mm
Powder : Norma MRP
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 82 50.72 2416 2074 31595 10403 92.8 1.579
-18.0 84 51.99 2480 2185 33860 10728 94.0 1.538
-16.0 86 53.26 2544 2299 36297 11036 95.2 1.497
-14.0 88 54.52 2608 2416 38920 11327 96.3 1.449
-12.0 90 55.79 2672 2537 41746 11597 97.2 1.402
-10.0 92 57.06 2736 2660 44794 11846 98.0 1.356
-08.0 94 58.33 2800 2786 48084 12071 98.7 1.312
-06.0 96 59.60 2864 2914 51638 12272 99.2 1.270
-04.0 98 60.86 2927 3044 55476 12445 99.6 1.229 ! Near Maximum !
-02.0 100 62.13 2990 3177 59639 12591 99.9 1.190 ! Near Maximum !
+00.0 103 63.40 3053 3311 64101 12708 100.0 1.152 ! Near Maximum !
+02.0 105 64.67 3115 3447 68911 12799 100.0 1.115 !DANGEROUS LOAD-DO NOT USE!
+04.0 107 65.94 3177 3585 74110 12882 100.0 1.080 !DANGEROUS LOAD-DO NOT USE!
+06.0 109 67.20 3238 3725 79736 12961 100.0 1.046 !DANGEROUS LOAD-DO NOT USE!
+08.0 111 68.47 3299 3866 85834 13034 100.0 1.014 !DANGEROUS LOAD-DO NOT USE!
+10.0 113 69.74 3359 4009 92457 13102 100.0 0.982 !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 103 63.40 3183 3600 78825 12175 100.0 1.061 !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba 103 63.40 2858 2901 50460 12797 96.4 1.273
Bullet : .284, 140, Nosler AccuBond 59992
Useable Case Capaci: 66.211 grain H2O = 4.299 cm³
Cartridge O.A.L. L6: 3.330 inch = 84.58 mm
Barrel Length : 24.0 inch = 609.6 mm
Powder : Norma MRP
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 84 53.44 2545 2014 31028 10490 90.1 1.500
-18.0 86 54.78 2615 2126 33289 10848 91.6 1.460
-16.0 88 56.11 2685 2241 35727 11191 93.0 1.420
-14.0 90 57.45 2755 2360 38359 11517 94.3 1.376
-12.0 92 58.78 2826 2483 41197 11823 95.4 1.330
-10.0 94 60.12 2897 2609 44270 12108 96.5 1.286
-08.0 96 61.46 2968 2738 47595 12370 97.4 1.243
-06.0 99 62.79 3038 2870 51197 12606 98.2 1.202
-04.0 101 64.13 3109 3005 55105 12815 98.8 1.162
-02.0 103 65.46 3179 3142 59350 12995 99.3 1.123 ! Near Maximum !
+00.0 105 66.80 3250 3283 63969 13144 99.7 1.086 ! Near Maximum !
+02.0 107 68.14 3319 3425 69004 13261 99.9 1.051 !DANGEROUS LOAD-DO NOT USE!
+04.0 109 69.47 3389 3569 74457 13344 100.0 1.016 !DANGEROUS LOAD-DO NOT USE!
+06.0 111 70.81 3457 3716 80382 13407 100.0 0.983 !DANGEROUS LOAD-DO NOT USE!
+08.0 113 72.14 3526 3864 86838 13465 100.0 0.951 !DANGEROUS LOAD-DO NOT USE!
+10.0 115 73.48 3594 4015 93890 13516 100.0 0.920 !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 105 66.80 3403 3600 79165 12608 100.0 0.997 !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba 105 66.80 3026 2847 50459 12993 94.7 1.203
Cartridge : .280 Ack Imp
Bullet : .284, 160, Nosler AccuBond 54932
Useable Case Capaci: 64.303 grain H2O = 4.175 cm³
Cartridge O.A.L. L6: 3.330 inch = 84.58 mm
Barrel Length : 24.0 inch = 609.6 mm
Powder : Norma MRP
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 82 50.72 2416 2074 31595 10403 92.8 1.579
-18.0 84 51.99 2480 2185 33860 10728 94.0 1.538
-16.0 86 53.26 2544 2299 36297 11036 95.2 1.497
-14.0 88 54.52 2608 2416 38920 11327 96.3 1.449
-12.0 90 55.79 2672 2537 41746 11597 97.2 1.402
-10.0 92 57.06 2736 2660 44794 11846 98.0 1.356
-08.0 94 58.33 2800 2786 48084 12071 98.7 1.312
-06.0 96 59.60 2864 2914 51638 12272 99.2 1.270
-04.0 98 60.86 2927 3044 55476 12445 99.6 1.229 ! Near Maximum !
-02.0 100 62.13 2990 3177 59639 12591 99.9 1.190 ! Near Maximum !
+00.0 103 63.40 3053 3311 64101 12708 100.0 1.152 ! Near Maximum !
+02.0 105 64.67 3115 3447 68911 12799 100.0 1.115 !DANGEROUS LOAD-DO NOT USE!
+04.0 107 65.94 3177 3585 74110 12882 100.0 1.080 !DANGEROUS LOAD-DO NOT USE!
+06.0 109 67.20 3238 3725 79736 12961 100.0 1.046 !DANGEROUS LOAD-DO NOT USE!
+08.0 111 68.47 3299 3866 85834 13034 100.0 1.014 !DANGEROUS LOAD-DO NOT USE!
+10.0 113 69.74 3359 4009 92457 13102 100.0 0.982 !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 103 63.40 3183 3600 78825 12175 100.0 1.061 !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba 103 63.40 2858 2901 50460 12797 96.4 1.273
- Thread starter
- #3
Ridgerunner665
Handloader
- Oct 28, 2008
- 2,516
- 299
If things go according to plan...I'll have some range verified data for MRP in 280 Ackley within a couple of weeks.
- Thread starter
- #5
longrangehunter
Handloader
- Jun 19, 2011
- 1,483
- 7
Hey Mike,
Is this powder really the same as RL-22? The reason I ask is in my Berger manual it's a lot faster in the 280 Rem. using the 168 gr. bullet then Reloader 22, (2848 vs. 2723).
Norma lists two MRP's: MRP and MRP2 which I understand is slightly slower, more like RL-25, and made for the 6.5x284 and the 6.5/06.
I have not found any Nosler LRAB's available for sale, but the other say I found 2 boxes of the Berger Classic Hunter 168's that I'd like to try out in my 280 AI using the Nosler brass I have. Can you run me a Quick Load using the 168 gr. Classic Hunter and MRP powder.
The bullet measures 1.350" long.
I have a 24" bbl.
Thanks Mike
Is this powder really the same as RL-22? The reason I ask is in my Berger manual it's a lot faster in the 280 Rem. using the 168 gr. bullet then Reloader 22, (2848 vs. 2723).
Norma lists two MRP's: MRP and MRP2 which I understand is slightly slower, more like RL-25, and made for the 6.5x284 and the 6.5/06.
I have not found any Nosler LRAB's available for sale, but the other say I found 2 boxes of the Berger Classic Hunter 168's that I'd like to try out in my 280 AI using the Nosler brass I have. Can you run me a Quick Load using the 168 gr. Classic Hunter and MRP powder.
The bullet measures 1.350" long.
I have a 24" bbl.
Thanks Mike
DrMike
Ballistician
- Nov 8, 2006
- 37,542
- 6,617
In previous communications with ballisticians knowledgeable in this particular issue, the consensus is that RL22 and MRP are the same powders. Differences can be accounted for through differences in burn rates in different lots. I do treat them as different powders, however, since the deterrents may well differ in either of these powders (which would also account for the slight differences in burn rates).
Cartridge : .280 Ack Imp
Bullet : .284, 168, Berger Hunt VLD G7 #28501
Useable Case Capaci: 64.333 grain H2O = 4.177 cm³
Cartridge O.A.L. L6: 3.330 inch = 84.58 mm
Barrel Length : 24.0 inch = 609.6 mm
Powder : Norma MRP
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 81 50.00 2369 2093 31710 10402 93.7 1.614
-18.0 83 51.25 2430 2203 33964 10716 94.9 1.572
-16.0 85 52.50 2492 2317 36378 11013 96.0 1.531
-14.0 87 53.75 2554 2433 38988 11291 96.9 1.481
-12.0 89 55.00 2615 2552 41789 11550 97.8 1.434
-10.0 91 56.25 2677 2673 44806 11786 98.5 1.388
-08.0 93 57.50 2738 2797 48056 12000 99.0 1.344
-06.0 95 58.75 2799 2923 51562 12188 99.5 1.301
-04.0 97 60.00 2860 3051 55339 12350 99.8 1.260 ! Near Maximum !
-02.0 99 61.25 2920 3181 59376 12485 100.0 1.220 ! Near Maximum !
+00.0 101 62.50 2980 3312 63712 12593 100.0 1.182 ! Near Maximum !
+02.0 103 63.75 3039 3445 68381 12688 100.0 1.145 !DANGEROUS LOAD-DO NOT USE!
+04.0 105 65.00 3098 3580 73413 12778 100.0 1.110 !DANGEROUS LOAD-DO NOT USE!
+06.0 107 66.25 3156 3716 78843 12864 100.0 1.076 !DANGEROUS LOAD-DO NOT USE!
+08.0 109 67.50 3214 3854 84712 12945 100.0 1.043 !DANGEROUS LOAD-DO NOT USE!
+10.0 111 68.75 3272 3994 91066 13021 100.0 1.012 !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 101 62.50 3102 3590 78100 12079 100.0 1.090 !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba 101 62.50 2795 2914 50163 12769 97.0 1.306
Cartridge : .280 Ack Imp
Bullet : .284, 168, Berger Hunt VLD G7 #28501
Useable Case Capaci: 64.333 grain H2O = 4.177 cm³
Cartridge O.A.L. L6: 3.330 inch = 84.58 mm
Barrel Length : 24.0 inch = 609.6 mm
Powder : Norma MRP
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 81 50.00 2369 2093 31710 10402 93.7 1.614
-18.0 83 51.25 2430 2203 33964 10716 94.9 1.572
-16.0 85 52.50 2492 2317 36378 11013 96.0 1.531
-14.0 87 53.75 2554 2433 38988 11291 96.9 1.481
-12.0 89 55.00 2615 2552 41789 11550 97.8 1.434
-10.0 91 56.25 2677 2673 44806 11786 98.5 1.388
-08.0 93 57.50 2738 2797 48056 12000 99.0 1.344
-06.0 95 58.75 2799 2923 51562 12188 99.5 1.301
-04.0 97 60.00 2860 3051 55339 12350 99.8 1.260 ! Near Maximum !
-02.0 99 61.25 2920 3181 59376 12485 100.0 1.220 ! Near Maximum !
+00.0 101 62.50 2980 3312 63712 12593 100.0 1.182 ! Near Maximum !
+02.0 103 63.75 3039 3445 68381 12688 100.0 1.145 !DANGEROUS LOAD-DO NOT USE!
+04.0 105 65.00 3098 3580 73413 12778 100.0 1.110 !DANGEROUS LOAD-DO NOT USE!
+06.0 107 66.25 3156 3716 78843 12864 100.0 1.076 !DANGEROUS LOAD-DO NOT USE!
+08.0 109 67.50 3214 3854 84712 12945 100.0 1.043 !DANGEROUS LOAD-DO NOT USE!
+10.0 111 68.75 3272 3994 91066 13021 100.0 1.012 !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 101 62.50 3102 3590 78100 12079 100.0 1.090 !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba 101 62.50 2795 2914 50163 12769 97.0 1.306
longrangehunter
Handloader
- Jun 19, 2011
- 1,483
- 7
Thanks Mike and Scotty,
I went back to Cabelas and they didn't have any MRP left...... I do have a new lot of RL-22, but when I had tried it with the 156 Oryx, the 160 N. Fork and the 160 TSX years ago in the 280 AI I wasn't all that impressed and went back to the loads Kenny gave me with the gun.
I was thinking of either of using IMR-7828, or H4831SC since they seem to have worked for Nosler w/the AI. It looked like the MRP and 7828 had the best velocity and H4831 down about 100 fps in the Berger manual.
I thought since I have these 200 pieces of Nosler brass I'd test them out w/the Berger bullets, and keep the Remington brass for the two loads I have from Kenny. Now it's just a question of picking a powder to quickly come up with a load, I'm not a fan of burning up powder and bullets to test everything under the sun! So hopefully I can get this done with 20-25 pieces?
I went back to Cabelas and they didn't have any MRP left...... I do have a new lot of RL-22, but when I had tried it with the 156 Oryx, the 160 N. Fork and the 160 TSX years ago in the 280 AI I wasn't all that impressed and went back to the loads Kenny gave me with the gun.
I was thinking of either of using IMR-7828, or H4831SC since they seem to have worked for Nosler w/the AI. It looked like the MRP and 7828 had the best velocity and H4831 down about 100 fps in the Berger manual.
I thought since I have these 200 pieces of Nosler brass I'd test them out w/the Berger bullets, and keep the Remington brass for the two loads I have from Kenny. Now it's just a question of picking a powder to quickly come up with a load, I'm not a fan of burning up powder and bullets to test everything under the sun! So hopefully I can get this done with 20-25 pieces?
- Nov 4, 2004
- 25,595
- 9,735
I have read that MRP and RL 22 are one in the same but I would treat them as different powders.
I always wanted to try MRP but never have because RL 22 has been just too good to me.
JD338
I always wanted to try MRP but never have because RL 22 has been just too good to me.
JD338
- Thread starter
- #11
Back in the 90's, in the only 280 AI I ever had, I used 61gr R22, BR2 primer, Winchester cases and the Nosler 150 BT. I had worked up the load here in Utah around 60 deg/ 5,000 ft elevation and had a super tight bolt lift/ flat primer (which is waaay bad in an Ackley! ha) in Texas at 90 deg/170 ft with the same load/rifle. I never had a problem with temp stability when it got colder though. I like/use a lot of R22. 7828 is another fine powder, in fact, as far as I can tell, almost the same as R22/MRP at the bench/chrono. Good luck to you.
longrangehunter
Handloader
- Jun 19, 2011
- 1,483
- 7
Preacher,
Back in Jackson, SC where Jarrett had developed two loads for a rifle I purchased, those same loads were way too hot where I lived in MT at 5,600 feet and I had to reduce those loads by 1.5 grains on average. Some have said elevation has nothing to do with pressure, but I'm not so sure? I've seen plastic water bottles shrink up from elevation changes and figured something has to effect the air inside so why not inside a cartridge case if loaded at very low elevation and then shot at above 5,000 feet from where it had been developed.
Back in Jackson, SC where Jarrett had developed two loads for a rifle I purchased, those same loads were way too hot where I lived in MT at 5,600 feet and I had to reduce those loads by 1.5 grains on average. Some have said elevation has nothing to do with pressure, but I'm not so sure? I've seen plastic water bottles shrink up from elevation changes and figured something has to effect the air inside so why not inside a cartridge case if loaded at very low elevation and then shot at above 5,000 feet from where it had been developed.
Ridgerunner665
Handloader
- Oct 28, 2008
- 2,516
- 299
Things didn't go according to plan...not gonna have my rifle until later on in December.Ridgerunner665":2ebgljcv said:
DrMike
Ballistician
- Nov 8, 2006
- 37,542
- 6,617
Cooler weather will permit you more bench time as the rifle will cool more readily. :grin: See, it's all a matter of perspective. Now, don't you feel better? Glad to help.
Ridgerunner665
Handloader
- Oct 28, 2008
- 2,516
- 299
Lol...the only thing that I fell bad about is that now I'm not sure I'll be home when the rifle gets here...makes getting it home from the FFL complicated, but we'll figure it out.
And I may be home...I just don't know what December will bring as far as work is concerned.
And I may be home...I just don't know what December will bring as far as work is concerned.
