375 Ruger with 300 Grain Sierra Gameking

clearwater

Handloader
Feb 5, 2005
552
401
Finally got the courage to shoot some full powder loads thru my 375 Ruger.

It's a Mossberg Patriot plastic fantastic and weighs less than 7 lbs scoped. With Staball and 300 grain Sierra Gamekings, (and a small sandbag between my shoulder and the stock) it did okay. I have been shooting a lot of cast loads with it.

At 50 yards, 4 out of 5 shots went under a inch. One outlier is flinch- I was anticipating it would hurt, tho with the sandbag it did not.
 

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I put a dozen rounds through my 375 H&H Mag the other day. I did 3 shots with 4 different bullets-
Nosler 260 gr E-Tip
Speer 270 gr SPBT
Hornady 270 gr Spire Point
Barnes 250 gr TTSX
1 shot each at 100, 200 and 250 yards.
POI was pretty close at all distances.
I really like my 375!

JD338
 
Yup,I will need to add some weight if I use these loads for hunting. Right now it shoots cast very well, and a starting load with 235 grain speer hot core has tolerable recoil. Similar to 30-06.

Being inexpensive and durable I bring it to deer hunting camp as a backup. The heavier cast loads have a point blank range of 200 yards and energy of 1300 ft/lbs at that distance. Where the terrain is steep and weather is miserable snain with fog, this is the rifle I carry. If it gets wet or I drop it, it matters less than the ones with Grandad's hand made stocks.

I paid $200+ for it at Sportsmans. Bout the same as 2 or 3 boxes of factory ammo. I wouldn't recommend this caliber if you don't reload. Even then, the brass has been unavailable since Covid. Shooting cast keeps it cheap and the brass lasts a long time. I buy the cast bullets. It has a nice trigger and a smooth bolt. The stock is a little long for use with thick winter clothes.
 
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I haven't shot my Ruger #1 in .375 H&H in a long time. I'd have to dig deep to even find my data for my cast bullet load. Trying to go from memory, the powder was H4350 and the bullet the RCBS #375-250-FN which casts a 270 gr. flat nose bullet at roughly 2000 to 200 FPS based on the data I have. Recoil in the #1 was about like a stiff 220 gr. load from a 30-06 or close to factory .300 H&H 150 gr. loads. Brass life was more than excellent as I've gotten 20 reloads from that one box of brass. Primer pockets are still reasonably snug and necks were annealed before each fifth reloading.

The only other .375 I own is a Ruger M77 Tang safety in .375 Taylor, AKA .375 Chatfield-Taylor by its designer Robert Chatfield Taylor although the barrel is stamped .375/338 Mag. Handloaded using standard .375 270 and 300 gr. bullets one can easily duplicate the older .375 H&H Magnum. Rifle sits in a Ramline stock and total weight is around 7.5 pounds. You do notice it when you pull trigger. I built the rifle for use on an elk hunt that was supposed to be in Idaho in steep dark timber country and maybe do another up in Washington state on the Olympic Penninsula. The rifle has an early all steel Weaver K4 scope with a post and crosshair reticle. That second hunt fell through when they banned logging in the area to save "the owl". The only thing that rifle needed to make it all weather was some kind of metal finish like Cerakote.

I usually don't name my rifles but one day at the range I was done sighting in and just shooting in various position when a fellow shooter came up and asked about the rifle. After answering a few questions he said he'd like to try it out so I load one of the rounds with the 300 gr. Hornady round nose and said to keep it real snug against your shoulder as it comes back rather snappy. He shot it and said that rifle hits like a hammer at both ends and thus, the rifle now holds the name of , "The Hammer." He thanked me for letting him shoot the rifle and went back to his bench rubbing his shoulder. I designed the rifle to to shoot the round nose Hornady for the hunt than never came about. The person up in Idaho who was running the hunt for us passed away and his relative said no to the hunt. These days, taking my age into consideration and that rifle's kick, I'm not taking any chances of a possible detached retina. I did find that H4350 worked the best in that rifle and was very accurate. ES spreads between 270 gr. bullets and the 300 gr. bullets ES, 5 FPS for one and 4 FPS for the other. I just don't remember which was which. Brass is Winchester .458 Mag run through the .375/338 sizing die and loaded to full power. Shoots just fine that way and no different after being fire formed. It's one of the easiest cartridges I've ever worked with.
Edited to fix all my spelling errors. I must have been quite tired the day I wrote this. My bad.
Paul B.
 
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It's a Mossberg Patriot plastic fantastic and weighs less than 7 lbs scoped.
Yes that will get your attention as well as testing your scope mounts😁
My 375 Wby is braked and is a pleasure to shoot. With cast powder coated bullets Blue Dot is my go to powder.
 
So does anyone have data for this combo, (375 ruger with 300 grain), using faster powders? The old IMR manual lists 375 H&H loads with SR4759, IMR 4227, IMR 4198, IMR 4320. I have these powders and would like to experiment with a bit lighter loads. I also have RX7. Quickload?
 
Code:
Cartridge          : .375 Ruger
Bullet             : .375, 300, Nosler PART SP 44845
Useable Case Capaci: 83.149 grain H2O = 5.399 cm³
Cartridge O.A.L. L6: 3.340 inch = 84.84 mm
Barrel Length      : 22.0 inch = 558.8 mm
Powder             : Alliant Reloder-7

Predicted data by increasing and decreasing the given charge,
incremented in steps of 1.0% 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

-10.0   71    52.38   2197    3214   46949   6546    100.0    1.350
-09.0   71    52.96   2213    3263   48151   6596    100.0    1.335
-08.0   72    53.54   2230    3312   49378   6645    100.0    1.320
-07.0   73    54.13   2246    3361   50629   6694    100.0    1.305
-06.0   74    54.71   2262    3410   51905   6743    100.0    1.290
-05.0   75    55.29   2279    3459   53207   6792    100.0    1.276  ! Near Maximum !
-04.0   75    55.87   2295    3508   54536   6840    100.0    1.262  ! Near Maximum !
-03.0   76    56.45   2311    3558   55891   6888    100.0    1.249  ! Near Maximum !
-02.0   77    57.04   2327    3607   57274   6936    100.0    1.235  ! Near Maximum !
-01.0   78    57.62   2343    3657   58686   6983    100.0    1.222  ! Near Maximum !
+00.0   78    58.20   2359    3706   60125   7030    100.0    1.209  ! Near Maximum !
+01.0   79    58.78   2375    3756   61594   7077    100.0    1.197  !DANGEROUS LOAD-DO NOT USE!
+02.0   80    59.36   2390    3806   63093   7123    100.0    1.185  !DANGEROUS LOAD-DO NOT USE!
+03.0   81    59.95   2406    3856   64623   7169    100.0    1.172  !DANGEROUS LOAD-DO NOT USE!
+04.0   82    60.53   2422    3906   66184   7215    100.0    1.160  !DANGEROUS LOAD-DO NOT USE!
+05.0   82    61.11   2437    3957   67777   7261    100.0    1.149  !DANGEROUS LOAD-DO NOT USE!
 
Code:
Cartridge          : .375 Ruger
Bullet             : .375, 300, Nosler PART SP 44845
Useable Case Capaci: 83.149 grain H2O = 5.399 cm³
Cartridge O.A.L. L6: 3.340 inch = 84.84 mm
Barrel Length      : 22.0 inch = 558.8 mm

Predicted Data for Indicated Charges of the Following Powders.
Matching Maximum Pressure: 62004 psi, or 427 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 !

8 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
---------------------------------  -----------------------------------------------------------------
Alliant Reloder-26 *C              108.7     89.6     5.81    2704   100.0    62004   11060   1.137  ! Near Maximum !
Norma MRP *C                       109.3     87.5     5.67    2672    99.3    62004   11103   1.140  ! Near Maximum !
ReloadSwiss RS 60 *T                99.2     79.7     5.17    2649   100.0    62004    9881   1.137  ! Near Maximum !
ReloadSwiss RS 70 *C               101.9     83.2     5.39    2644   100.0    62004   10365   1.137  ! Near Maximum !
Elcho 17                            98.2     79.0     5.12    2630   100.0    62004    9822   1.144  ! Near Maximum !
Alliant Reloder-17 *T               98.2     79.0     5.12    2630   100.0    62004    9822   1.144  ! Near Maximum !
IMR 7828 SSC                       109.0     85.8     5.56    2628    96.8    62004   10783   1.137  ! Near Maximum !
Vihtavuori N560 *C                 110.0     86.1     5.58    2627    96.2    60071   11114   1.156  ! Near Maximum !
Alliant Reloder-16 *C *T           103.2     77.1     4.99    2619   100.0    62004    9805   1.140  ! Near Maximum !
Bofors RL16 TZ *C *T               103.2     77.1     4.99    2619   100.0    62004    9805   1.140  ! Near Maximum !
ADI AR 2213                        109.8     85.0     5.51    2613    96.6    62004   10672   1.138  ! Near Maximum !
Vihtavuori N555 *C*T               110.0     82.7     5.36    2610   100.0    61164    9970   1.175  ! Near Maximum !
Accurate MAGPRO                    110.0     89.6     5.81    2607    94.4    59255   11075   1.168  ! Near Maximum !
Raufoss RA15 *C                    110.0     85.2     5.52    2606    97.9    59325   10760   1.167  ! Near Maximum !
Bofors RP5/NP ~approximation       110.0     85.2     5.52    2606    97.9    59325   10760   1.167  ! Near Maximum !
Alliant Reloder-22 *C              110.0     85.2     5.52    2606    97.9    59325   10760   1.167  ! Near Maximum !
ReloadSwiss RS 62                  101.7     81.7     5.30    2605   100.0    62004    9920   1.163  ! Near Maximum !
Somchem S365                       105.3     80.3     5.20    2603   100.0    62004    9367   1.157  ! Near Maximum !
PB Clermont PCL 518                103.7     82.1     5.32    2601    99.5    62004   10147   1.153  ! Near Maximum !
PB Clermont PCL 511                 99.6     81.4     5.27    2599    99.7    62004   10086   1.153  ! Near Maximum !
Ramshot Hunter                     102.9     81.5     5.28    2598    99.7    62004   10071   1.154  ! Near Maximum !
Ramshot Magnum                     110.0     91.8     5.95    2598    98.5    61334   10309   1.145  ! Near Maximum !
Alliant Reloder-19 *C              107.5     82.4     5.34    2595    98.1    62004   10302   1.149  ! Near Maximum !
Rottweil R905                      108.0     82.1     5.32    2594    98.2    62004   10212   1.154  ! Near Maximum !
Winchester 760                      97.2     78.8     5.11    2592    99.2    62004   10062   1.157  ! Near Maximum !
Hodgdon H414                        97.2     78.8     5.11    2592    99.2    62004   10062   1.157  ! Near Maximum !
ADI AR 2209                        106.7     81.3     5.27    2591    97.9    62004   10212   1.143  ! Near Maximum !
Bofors RP14 ~approximation         108.2     83.0     5.38    2589    98.0    62004   10223   1.150  ! Near Maximum !
Norma URP *C                       102.5     77.7     5.03    2581   100.0    62004    9658   1.161  ! Near Maximum !
Bofors RP19 ~approximation         102.5     77.7     5.04    2581   100.0    62004    9655   1.161  ! Near Maximum !
Vihtavuori N550 *C*T                99.5     77.9     5.05    2581   100.0    62004    9787   1.166  ! Near Maximum !
Accurate 4350                      101.8     78.0     5.06    2579   100.0    62004    9625   1.176  ! Near Maximum !
Hodgdon LVR                         99.8     76.5     4.96    2575    99.9    62004    9631   1.158  ! Near Maximum !
Norma 204 *C                       101.8     80.6     5.22    2571    97.8    62004   10003   1.151  ! Near Maximum !
Bofors RP4 ~approximation          105.1     80.6     5.22    2571    97.8    62004   10003   1.151  ! Near Maximum !
Raufoss RA4                        105.1     80.6     5.22    2571    97.8    62004   10003   1.151  ! Near Maximum !
IMR 4831                           107.6     78.9     5.12    2566   100.0    62004    9443   1.170  ! Near Maximum !
Somchem S385                       107.7     83.5     5.41    2564    98.8    62004    9866   1.168  ! Near Maximum !
Hodgdon H4831 SC *T                108.3     84.0     5.44    2561    96.0    62004   10034   1.149  ! Near Maximum !
Bofors RP4 NT *C ~approximation    102.6     79.9     5.18    2553    99.0    62004    9690   1.164  ! Near Maximum !
Winchester Supreme 780             105.7     85.4     5.53    2549    97.8    62004    9739   1.154  ! Near Maximum !
Hodgdon Hybrid 100V                105.2     78.0     5.06    2547   100.0    62004    8868   1.161  ! Near Maximum !
Alliant Reloder-23 *C *T           110.0     82.5     5.34    2545   100.0    55090    9709   1.207  ! Near Maximum !
Bofors RP36 ZT *C *T               110.0     82.5     5.34    2545   100.0    55090    9709   1.207  ! Near Maximum !
SNPE Vectan SP 12                  110.0     90.0     5.83    2542    95.8    55208   10702   1.196  ! Near Maximum !
Vihtavuori N160 *C                  99.4     77.8     5.04    2542   100.0    62004    9135   1.164  ! Near Maximum !
Lovex S070                         101.8     77.2     5.00    2539    99.3    62004    9534   1.175  ! Near Maximum !
Shooters World SW4350              101.8     77.2     5.00    2539    99.3    62004    9534   1.175  ! Near Maximum !
Rottweil R904                      105.8     79.9     5.18    2538    96.8    62004    9696   1.157  ! Near Maximum !
Hodgdon H380                        94.4     73.9     4.79    2538   100.0    62004    9299   1.174  ! Near Maximum !
PB Clermont PCL 517                110.0     90.0     5.83    2537    95.6    54895   10698   1.199  ! Near Maximum !
Norma 203 old                       94.9     73.5     4.76    2534   100.0    62004    8946   1.184  ! Near Maximum !
Winchester WXR                     110.0     83.4     5.40    2529    96.7    53921   10528   1.219  ! Near Maximum !
IMR 4955 Enduron *C*T              109.4     81.6     5.29    2529    96.2    62004    9725   1.158  ! Near Maximum !
Rottweil R903                       97.0     73.6     4.77    2529   100.0    62004    8867   1.184  ! Near Maximum !
Accurate 3100                      110.0     84.3     5.46    2527    99.4    59273    9589   1.202  ! Near Maximum !
Shooters World Long Rifle          100.5     75.4     4.88    2519    99.7    62004    9193   1.176  ! Near Maximum !
Lovex S065                         100.5     75.4     4.88    2519    99.7    62004    9193   1.176  ! Near Maximum !
Rottweil R907                       99.2     74.6     4.84    2516    98.8    62004    9336   1.172  ! Near Maximum !
IMR 4007 SSC                        96.1     74.7     4.84    2516    98.8    62004    9329   1.172  ! Near Maximum !
 
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