Looking for some opinions on load development for my new build. I just got my new rifle and custom dies for a rifle I'm going to try. It's a one off cal so there is no load for it in any of the data sites or books. It's basically a .375 Ruger case necked down to .358 which is very close to a .358 norma mag just a hair bigger. I'd like to try H1000 powder. The next closest that I Could find is .358 STA but that's a bigger case although they do have data for H1000. What I've been reading for the last while is to fill the case to the bottom of the neck and weigh the powder. Then try 70% of that number and try it. I did that and the case to the bottom of the neck holds 88.1grs. Multiplied that by .3 and subtracted from 88.1 and that gives me 61.6grs. The data for the 358 norma is comparable to the min loads and that case is a hair smaller in all dimensions. The brass will need to fire form a bit in the shoulders so I'll have to get the real results on the Chrony after the second load but just wondering what guys that know think of starting with that load.
Wildcat load development
- Thread starter gunner72
- Start date
If it were me, I would fire form first, with small charge of fast powder and cream of wheat.
Then you have exact case dimensions to work with.
Then I would start with 63Gr(but not sure the bullet you are working with??) this can change things big time.
I have several wildcats, and I have done similar things, I look for the powder I am wanting to use, look for a similar dimensioned case, then back off from there.
In this case, any powder that works for the ruger should work for your design, and start low and work up.
I would not do the powder to bottom of neck, I don't believe that is a safe way of starting.
I would also, ask someone with the quick load program to run the numbers for you and that should give you a start as well.
I load for the 358 Norma, and you should be able to use any load data for it and work up.
Not sure H1000 is the ideal choice though. H4350 I would think would be better.
Then you have exact case dimensions to work with.
Then I would start with 63Gr(but not sure the bullet you are working with??) this can change things big time.
I have several wildcats, and I have done similar things, I look for the powder I am wanting to use, look for a similar dimensioned case, then back off from there.
In this case, any powder that works for the ruger should work for your design, and start low and work up.
I would not do the powder to bottom of neck, I don't believe that is a safe way of starting.
I would also, ask someone with the quick load program to run the numbers for you and that should give you a start as well.
I load for the 358 Norma, and you should be able to use any load data for it and work up.
Not sure H1000 is the ideal choice though. H4350 I would think would be better.
Use a starting load and work up . Its not a bad idea to fire form a case using pistol powder and cow. Once you see the velocity vs powder charge you can compair it to 358 norma data and see what you are working with, since it so close and even a little bigger case. You will likly have slightly lower pressure.
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Do not reduce H1000 by 70% - you're going to blow yourself up. Google seconday explosion effect.
A 35-375 Ruger will hold about 13% more powder than a 358 Norma Mag - use 358NM data and work up. You'll see 3% more velocity than the 358NM at the same pressures, so about 85 fps.
H1000 will be too slow burning for optimum speeds. Better suited would be Varget, H4350, H414, IMR 4064, IMR 4350, Win760, Ramshot BigGame
A 35-375 Ruger will hold about 13% more powder than a 358 Norma Mag - use 358NM data and work up. You'll see 3% more velocity than the 358NM at the same pressures, so about 85 fps.
H1000 will be too slow burning for optimum speeds. Better suited would be Varget, H4350, H414, IMR 4064, IMR 4350, Win760, Ramshot BigGame
this might be the closest you find to 35-375 Ruger data. Assuming 3.34" OAL, 99gr H2O case capacity (like the parent case), and a bullet jump of .050" to lands
Code:
Cartridge : .35-375 Ruger
Bullet : .358, 225, Nosler AccuBond 50712
Useable Case Capaci: 84.141 grain H2O = 5.463 cm³
Cartridge O.A.L. L6: 3.340 inch = 84.84 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 104 %
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 !
109 loads produced a Loading Ratio below user-defined minimum of 80%. 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-26 104.0 86.7 5.62 2986 99.3 56396 10767 1.124 ! Near Maximum !
Alliant Reloder-17 95.5 77.7 5.04 2974 100.0 60000 9666 1.091 ! Near Maximum !
Alliant Reloder-16 102.1 77.1 5.00 2942 99.9 60000 9543 1.102 ! Near Maximum !
Ramshot Hunter 100.1 80.2 5.20 2921 98.5 60000 9797 1.104 ! Near Maximum !
Hodgdon H414 94.4 77.4 5.02 2905 97.7 60000 9744 1.109 ! Near Maximum !
Winchester 760 94.4 77.4 5.02 2905 97.7 60000 9744 1.109 ! Near Maximum !
Alliant Reloder-19 104.0 80.7 5.23 2892 95.8 58820 9858 1.108 ! Near Maximum !
Hodgdon CFE223 84.8 73.2 4.75 2882 100.0 60000 9001 1.116 ! Near Maximum !
Ramshot Big Game 89.8 74.2 4.81 2880 99.9 60000 9032 1.115 ! Near Maximum !
IMR 4831 104.0 77.2 5.01 2877 99.6 59639 9247 1.122 ! Near Maximum !
Hodgdon Hybrid 100V 102.3 76.8 4.97 2876 100.0 60000 8748 1.109 ! Near Maximum !
IMR 7828 SSC 104.0 82.9 5.37 2874 93.1 55870 10084 1.138 ! Near Maximum !
IMR 4895 89.4 69.4 4.50 2874 100.0 60000 9045 1.124 ! Near Maximum !
Alliant Reloder-15 90.3 70.1 4.54 2864 99.8 60000 9018 1.125 ! Near Maximum !
Hodgdon BL-C2 85.2 72.1 4.67 2860 100.0 60000 8800 1.127 ! Near Maximum !
Winchester 748 82.8 69.1 4.48 2855 100.0 60000 8473 1.122 ! Near Maximum !
IMR 4320 92.3 70.4 4.56 2851 99.9 60000 8689 1.115 ! Near Maximum !
Hodgdon H380 91.7 72.7 4.71 2851 99.3 60000 9109 1.127 ! Near Maximum !
Hodgdon H4895 87.2 67.7 4.38 2850 100.0 60000 8745 1.128 ! Near Maximum !
Hodgdon H4350 101.6 77.1 5.00 2842 97.0 60000 9165 1.117 ! Near Maximum !
IMR 4350 99.7 76.9 4.98 2842 97.1 60000 9152 1.117 ! Near Maximum !
IMR 3031 89.3 64.8 4.20 2835 100.0 60000 7989 1.129 ! Near Maximum !
Alliant Reloder-22 104.0 81.5 5.28 2833 94.4 52810 10029 1.147 ! Near Maximum !
Hodgdon VARGET 93.2 69.9 4.53 2832 99.8 60000 8707 1.123 ! Near Maximum !
Ramshot TAC 86.3 72.1 4.67 2830 98.9 60000 8925 1.127 ! Near Maximum !
IMR 4451 Enduron 95.4 73.1 4.74 2829 97.6 60000 9028 1.121 ! Near Maximum !
IMR 4064 93.8 68.7 4.45 2823 99.9 60000 8546 1.126 ! Near Maximum !
Hodgdon H4831 SC 104.0 81.5 5.28 2819 92.5 56972 9432 1.124 ! Near Maximum !
IMR 8208 XBR 86.3 66.9 4.34 2819 100.0 60000 8299 1.130 ! Near Maximum !
IMR 4166 Enduron 95.1 70.6 4.58 2808 97.8 60000 8803 1.128 ! Near Maximum !
Hodgdon H1000 104.0 79.8 5.17 2547 86.6 41731 8649 1.288really if you were worried about the load at all for over pressure. H4895 can be loaded to 60% the max load. so in this case it would be safe to start at a about 40gr and work your way up to about 67gr and watch velocity, i wouldNT go above 2850fps if using the h4895 regardless of the charge weight
back40sniper
CGN Regular
- Location
- South east Sask.
Don't know how much of a hurry you are in but I would try Sierra help line,800-223-8799, the guys there are very helpful and not much they haven't seen.
62grs H1000 could likely blow the gun up
My plinking load in my 35 WSM is getting 2725 fps with 250gr Hornadys and IMR4895. I also use 200gr ttsx at 3170 fps with RL 19.
There's some pretty good loads out there for the 35-375 Ruger. Guys have been playing with it for a long time, I looked at it when I build my 35 WSM and some of my noted data is from <2009
There's some pretty good loads out there for the 35-375 Ruger. Guys have been playing with it for a long time, I looked at it when I build my 35 WSM and some of my noted data is from <2009
H1000 is the wrong powder choice for that application. It's burn rate is much too slow. You should start with one of the 4350s or another powder with a similar burn rate. The starting load for 358 Norma Mag, or slightly more (since you have a slightly greater case capacity), is likely a good place to start. Increase load incrementally, and back off if you see pressure signs or groups open up.
