7mm remington mag

[lcq]

Hi All

I'm looking for some advice and perhaps a QuickLoad model. I'm trying to get my Nosler 160 AccuBond velocity up. Currently I'm getting 2748fps (pathetic) out of a 24" barrel. Hell I'm getting 2800fps out of my 20" 308 with a 150 Barnes. BTW factory 150 core-lokts are doing 3030fps looks like chrony is ok

Win Brass, Win LRP, IMR4350 59gr

I also have H-4831 and Supreme-780 and IMR-7828


just back from the range and 66.2gr ( 65.7 book max) W-780 gets sub moa at 2900 slightly flat primers but they are soft Winchester, no real pressure signs.

Next up 7828 I managed to find a pound.

Nosler and Hodgdon both claim 64gr max at 3015 and 2868 respectively.

Out of 63gr IMR7828 I got 2700 and the cases were smoked at 64.5 2803 and not even a flattened primer. By my back of the envelope calculation I will be close to your 66.9gr to squeak out 2900. so far it looks more promising for the W-780.

All help much appreciated

 

[DrMike]

In my 7 RM, I've used RL22 and RL25 with the 160 grain AB.

R 9.5 primer/160 g. AB/ 63.5 g. RL22 gives sub-MOA and ~3000 fps.

WLRM primer/160 g. AB/69.5 g. RL25 gives even better accuracy and ~3100 fps.

WLRM primer/160 g. PT/ 59.5 g. H100V gives me 0.5 MOA and ~3000 fps.

F215/160 g. TSX/67.5 g. IMR7828 gives sub-MOA and ~3000 fps.

Cartridge : 7 mm Rem. Mag.(SAAMI)
Bullet : .284, 160, Nosler AccuBond 54932
Useable Case Capaci: 72.296 grain H2O = 4.694 cm³
Cartridge O.A.L. L6: 3.290 inch = 83.57 mm
Barrel Length : 24.0 inch = 609.6 mm
Powder : IMR 7828

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 53.20 2404 2053 30900 10548 89.3 1.600
-18.0 84 54.53 2466 2161 33002 10908 90.7 1.559
-16.0 86 55.86 2529 2272 35250 11256 92.1 1.519
-14.0 88 57.19 2592 2387 37654 11591 93.3 1.476
-12.0 90 58.52 2655 2505 40228 11911 94.5 1.430
-10.0 92 59.85 2719 2626 42985 12213 95.5 1.385
-08.0 94 61.18 2782 2750 45940 12497 96.5 1.342
-06.0 97 62.51 2845 2876 49108 12761 97.3 1.301
-04.0 99 63.84 2909 3006 52510 13003 98.0 1.261 ! Near Maximum !
-02.0 101 65.17 2972 3137 56166 13221 98.6 1.222 ! Near Maximum !
+00.0 103 66.50 3035 3272 60099 13415 99.2 1.185 ! Near Maximum !
+02.0 105 67.83 3097 3408 64333 13582 99.5 1.149 !DANGEROUS LOAD-DO NOT USE!
+04.0 107 69.16 3160 3547 68899 13722 99.8 1.114 !DANGEROUS LOAD-DO NOT USE!
+06.0 109 70.49 3222 3687 73828 13834 100.0 1.080 !DANGEROUS LOAD-DO NOT USE!
+08.0 111 71.82 3283 3830 79141 13916 100.0 1.048 !DANGEROUS LOAD-DO NOT USE!
+10.0 113 73.15 3344 3974 84854 13985 100.0 1.016 !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 66.50 3177 3586 73020 12963 100.0 1.093 !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba 103 66.50 2835 2855 48547 13102 93.5 1.303

Cartridge : 7 mm Rem. Mag.(SAAMI)
Bullet : .284, 160, Nosler AccuBond 54932
Useable Case Capaci: 72.296 grain H2O = 4.694 cm³
Cartridge O.A.L. L6: 3.290 inch = 83.57 mm
Barrel Length : 24.0 inch = 609.6 mm

Predicted Data for Indicated Charges of the Following Powders.
Matching Maximum Pressure: 60000 psi, or 413 MPa
or a maximum loading ratio or filling of 110 %
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 !

38 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 N570 107.5 75.5 4.89 3107 96.3 60000 15298 1.191 ! Near Maximum !
Alliant Reloder-33 107.8 79.0 5.12 3094 96.6 60000 15117 1.191 ! Near Maximum !
odgdon Retumbo 110.0 73.7 4.78 3049 100.0 57761 13607 1.205 ! Near Maximum !
Norma MRP 2 106.4 70.9 4.59 3047 99.4 60000 13862 1.206 ! Near Maximum !
Alliant Reloder-25 104.2 69.1 4.48 3044 100.0 60000 12895 1.193 ! Near Maximum !
Vihtavuori N560 98.2 66.8 4.33 3040 98.8 60000 13826 1.197 ! Near Maximum !
Norma MRP 96.4 67.0 4.34 3040 100.0 60000 13401 1.204 ! Near Maximum !
IMR 7828 SSC 97.1 66.5 4.31 3033 99.1 60000 13410 1.185 ! Near Maximum !
IMR 7828 102.6 66.5 4.31 3033 99.1 60000 13410 1.185 ! Near Maximum !
Accurate MAGPRO 98.5 69.8 4.52 3033 97.8 60000 13947 1.204 ! Near Maximum !
Hodgdon H1000 107.4 70.8 4.59 3017 99.3 60000 13120 1.181 ! Near Maximum !
Alliant Reloder-22 98.4 66.3 4.30 3015 99.7 60000 13255 1.203 ! Near Maximum !
Winchester WXR 101.1 66.6 4.32 3014 99.7 60000 13274 1.203 ! Near Maximum !
Ramshot Magnum 98.5 71.5 4.63 3000 99.9 60000 12706 1.198 ! Near Maximum !
Alliant Reloder-19 95.4 63.6 4.12 2975 99.6 60000 12637 1.198 ! Near Maximum !
Norma 217 110.0 72.2 4.68 2964 99.7 51889 13902 1.284 ! Near Maximum !
Ramshot Hunter 91.1 62.7 4.06 2963 100.0 60000 12144 1.205 ! Near Maximum !
Hodgdon H4831 SC 96.8 65.2 4.23 2955 98.5 60000 12544 1.195 ! Near Maximum !
Hodgdon H4831 100.7 65.2 4.23 2955 98.5 60000 12544 1.195 ! Near Maximum !
Norma 204 90.6 62.4 4.04 2954 99.5 60000 12335 1.197 ! Near Maximum !
Hodgdon H870 110.0 75.7 4.91 2952 96.2 52018 14364 1.275 ! Near Maximum !
Norma URP 90.6 59.7 3.87 2939 100.0 60000 11620 1.212 ! Near Maximum !
Vihtavuori N170 110.0 72.5 4.70 2937 94.6 59687 12959 1.218 ! Near Maximum !
Winchester Supreme 780 94.4 66.3 4.30 2931 99.6 60000 12049 1.204 ! Near Maximum !
Alliant Reloder-50 110.0 79.3 5.14 2929 93.5 50512 14805 1.313
Vihtavuori N165 100.8 66.4 4.30 2924 99.8 60000 11813 1.209 ! Near Maximum !
Accurate 3100 98.6 65.7 4.26 2921 100.0 60000 11679 1.235 ! Near Maximum !
IMR 4831 95.0 60.6 3.93 2921 100.0 60000 11375 1.221 ! Near Maximum !
Hodgdon H4350 93.1 60.7 3.93 2915 99.9 60000 11633 1.201 ! Near Maximum !
IMR 4350 91.4 60.6 3.93 2914 99.9 60000 11606 1.201 ! Near Maximum !
Vihtavuori N160 100.9 64.5 4.18 2912 99.0 60000 11867 1.201 ! Near Maximum !
Hodgdon Hybrid 100V 93.0 60.0 3.88 2895 100.0 60000 10743 1.213 ! Near Maximum !

 

[lcq]

Thanks DrMike. It looks like Book Max is really conservative. I will wait for the weather to clear up and give it another go.

BTW have you ever necksized and crimped or is a crimp necessary?

 

[DrMike]

Yes, I neck size. A crimp is not necessary, though I have crimped in the past. Smoked necks indicate a light load. Increasing the charge will address that problem. Of course, do this with normal caution, watching for pressure signs. Oh, yes, welcome aboard. Glad to see you here.

 

[lcq]

Will do, thanks again

 

[Guy Miner]

It's always possible that your rifle has an extra-generous chamber or a large dia & length to the throat which might play a part in reducing the velocity.

Though I never had any problems with it, and the 7mm Rem mag was a favorite of mine for about 10 years, I have read that the 7mm Rem mag is subject to various unexplained pressure spikes and other problems. Why? I have no idea. It looks as good as any other belted magnum case to me. Perhaps variations in chamber & throat dimensions?

Look at RL-22, and work up. I never failed to break 3,000 fps from a 24" barrel, with 160 gr bullets, while using RL-22. Good accuracy too.

Regards, Guy

 

[OU812]

RL-22 and the 160 AccuBond were meant to be together. Work up to max in YOUR rifle and enjoy the accuracy and speed.

 

[Darkhorse]

It's always possible that your rifle has an extra-generous chamber or a large dia & length to the throat which might play a part in reducing the velocity.

Though I never had any problems with it, and the 7mm Rem mag was a favorite of mine for about 10 years, I have read that the 7mm Rem mag is subject to various unexplained pressure spikes and other problems. Why? I have no idea. It looks as good as any other belted magnum case to me. Perhaps variations in chamber & throat dimensions?

Regards, Guy

Guy, From what I've read, and from looking at some of my older loading manuals, variations in chamber dimensions are the main problem with the old 7 rem mag.
I had an older Hornaday book that had max loads many grains above those listed today. I shot and hunted with these loads with the 154 gr. spire point for years with no problems. These loads did give exceptional accuracy though. I loaned that manual out and it never came back. I wish I had it for comparison.
I have an older Speer that goes into the chamber problems with the 7 mag. in some detail.
Back around '84 a friend gave me a coffee can full of once fired brass from his then new, M700 7 mag. I noticed a shiney ring above the belt and checked them with a paper clip. All of them were ready to separate. I even broke a few just with my fingers. This was after 1 firing. Classic case of sloppy reaming from the factory.
In comparison; My M700 7 mag has never had a casehead separation. I have some old brass and anneal regularly and only discard when the primer pocket gets too loose.
Knowing this history is good reason to treat each rifle as a rule unto itself, and carefully work up loads using every available method of checking pressure. I include a set of .0001 micrometers as essential to all my pressure checking these days.
I consider it essential that handloaders aquire a 0-1" mic. graduated in 1/10,000's and learn to use them properly, and apply today's methods of measurement whenever working up max. loads.

 

[Guy Miner]

Nicely written!

 

[Oldtrader3]

I use 66.0 grs of IMR 7828 SSC with a Fed 215MM primer and 160 Partitions. I only get about 2900 fps with W-W brass and a 24 inch barrel. However my barrel is probably over 45 years old.

 

[baltz526]

64-66 gr of H4831 with 160gr Bullets in the 7mm Rem Mag has given 3000fps give or take 50fps in a few 7mm for me. 64gr 2950, 65gr 3000, 66gr 3020 in 24" and 3070fps in a 26" using the Sierra HPBT. RE22 65gr gives me 3013fps out of the 26" using the 160gr AccuBond

 

[lcq]

64-66 gr of H4831 with 160gr Bullets in the 7mm Rem Mag has given 3000fps give or take 50fps in a few 7mm for me. 64gr 2950, 65gr 3000, 66gr 3020 in 24" and 3070fps in a 26" using the Sierra HPBT. RE22 65gr gives me 3013fps out of the 26" using the 160gr AccuBond

today 61gr H4831 160 AccuBond 2750fps
65gr 7828 160 AccuBond 2809fps

I'm beginning to think Guy and OU812 are onto something about a generous chamber but

factory 150 cor-lokt 3030 fps
factory 150 Powermax 3060 fps win claims 3090

how much will seating depth affect the vely? I'm 25 thou off the lands I can always seat deeper or I can use the factory crimp and put a firm crimp on the bullet like the factory rounds

 

[sbsmith]

If you're going to use heavy bullets in the 7mag, ( 160 & 175) H1000 separates itself from the other players with excellent accuracy, 3135 fps w/160 AccuBond. There is a load in Propellant Profiles that is substantially above what is printed here for H1000 so I will let you be the judge. I have used that load with no issues and have been well satisfied for years using the Nosler 160 AccuBond.
just my .02
sbsmith

 

[lcq]

If you're going to use heavy bullets in the 7mag, ( 160 & 175) H1000 separates itself from the other players with excellent accuracy, 3135 fps w/160 AccuBond. There is a load in Propellant Profiles that is substantially above what is printed here for H1000 so I will let you be the judge. I have used that load with no issues and have been well satisfied for years using the Nosler 160 AccuBond.
just my .02
sbsmith

Thanks for the suggestion but H1000 isn't available where I am so I have to make due with what I have. If ever some surfaces I'll scoop it.

 

[lcq]

Well I have settled on H-4831 65.5 @ 2950 and the primers look cherry.

Thanks to all for the help and suggestions. Now to the 243

Africa awaits

 

[gerry]

2950 with a 160 gr AccuBond is a good place to be, sounds like you found a great load.

 

[DrMike]

Well I have settled on H-4831 65.5 @ 2950 and the primers look cherry.

That is potent medicine, for sure.

 

[Oldtrader3]

I can not complain, using IMR's 4350, 4831 and 7828 SSC at about 2900+ in my 7mm Rem Mag has consistently killed game since 1963 for me. The deer never cared about the loss of 75-100 fps. They just died.

Funny thing though, that my .280 Rem kills deer just as well and is very nearly as fast as my 7mm Mag with 160 gr Partitions or Accubonds and 8 grains less powder. If I did not have so much invested I my &mm Mag custom rifle, I would trade it for a .280 Rem in a minute!