Home Forums Hunting & Shooting Express Rifles and Big Bores Only .450 Dakota/Rigby 97 grains H4350 500gn

Would anyone know approx. what velocity 97 grains H4350 will get with a 500gn projectile from 25" .450 Dakota/Rigby? 105 gns H4350 gets me 2300 fps and I want a practice load at 2000-2100 fps with 500's. Thank you.

That is a very light load for that powder and bullet weight.
I would recommend changing to Varget or 4064 if you plan on loads under 100grains, then your velocity goals are more easily attained.

Your on your own with this one.
Light loads under 100 grains using AR2209/H4350 is not recommended by the manufacturer where a minimum charge of 108 grains is the recommended starting load.

You have been advised to use a faster powder, that is all that can be recommended.

I do have Varget and H4895. I know H4895 should work ok with reduced loads around 2000-2100. Just don't know how much Varget or H4895 to use either. Note: The .450 Dakota/Rigby cases are marginally smaller by about 5 grains than the .460 Weatherby case. Also 105gns H4350 with 500's works superbly at 2300 fps.

Don't know if this will help you to start your reduced loads with H-4895, but I use 60.0 grains of it with Berry's 350 grain plated RNs for about 1740 fps MV from my Ruger RSM 23" bbl 450 Rigby.

This is Hogdon's guidance on the use of H-4895 for reduced loads in rifle cartridges.

I also use Trail Boss 27 gns for MV = 1320 fps (case capacity to base of seated 350 gn bullet = 37 gns).

For reference only, my hunting load is RL-17 102 gns vel @ 5 yds = 2380 fps with a CEB BBW#13 500 gn Safari Solid FP.

Given that my bbl is a couple of inches shorter than yours and IME H-4350 and RL-17 yield similar MVs with similar powder charges and bullets in high volume cases like the 450 Rigby Rimless, it seems my rifle is generating higher chamber pressures than yours. Only mentioning it to help compare possible starting loads.

It might be that your solids generate more pressure, if they are not a slightly smaller diameter. I am aware of the 60% rule with H4895. I load R17, in 2 other rifles and find it gives higher velocities than a similar weight charge of H4350. But there is no way I'd use it on a rifle I'd take to Africa where temps may be near 100 degrees.

RL-17 works just fine in Southern Africa. BTW have you taken a rifle loaded with RL-17 to Africa?

You’re right that it produces higher velocity than H-4350 but not much.

You’re free to disregard my input if irrelevant to your question. Just trying to provide some info. YMMV

No dog in this fight on my part.

There's no "fight" whatsoever. Temperatures regularly get over 100 even in countries south of equatorial Africa, where one may hunt buffalo for example. I'm just giving you input also, which you're free to disregard. Attempts to assist are appreciated, but so far, no one has given input to the question that is on point, which I understand, as it is unlikely that anyone actually knows.

Regarding H4895, The manufacturer of Mulwex AR2206H recommends a starting load of 95 grains for the .460 case and as you are using a case a few grains lighter in capacity, it's not excess pressure you have to contend with, with light charges, its the no man's land of using a powder not for its intended purpose. Erratic ignition, hangfires etc.

If you want to try Varget/AR2208, Around 85 grains will meet your goal.

Good luck with it.

With the H4895 load of 95 grains in the .460 case, that is listed as giving 2314 fps, and I would think would give even more fps in a smaller case with less freebore. That's well over my goal of 2000-2100 fps with a 500 for a practice load that is relatively light on scopes, stocks, screws etc. I would think perhaps 85 grains of H4895 might work though. With Varget and the 85 grain load, which should give the desired velocity, do you know whether that may give the hangfires? I thought H4895 might be better than Varget from the perspective of hangfires/secondary explosions etc.

I have suggested AR 2008/Varget which I have used in the .460 case. It will develop just over 2000fps using the 500gn bullet.

In your slightly smaller Rigby case, the load will not be excessive, but will likely be a little faster. Because the manufacturer recommends a minimum load exceeding your requirements for H4895, I would not recommend its use.

I have interchanged IMR 4064 and AR 2208 load for load with velocities near identical weight for weight


What I don't underatand is why you are wanting a 500gn bullet for a reduced load when there are 350gn and 450gn Barnes TSX and other brand options in 400gn and 450gn weight which would offer more with less recoil.

Thanks for the info. I will try the Varget load of 85 grains. I have lots of 500 gn projectiles and want only a slight reduction in recoil mainly so I don't break anything such as scope or stock.

Good discussion above.
I have measured my 450 Dakota gross water capacity at 138.8 grains, call it 139 rounded off.
The 460 WbyMag was 141 grains H2O rounded.
450 NE 3-1/4" was 129 grains H2O rounded.

Graeme Wright load data for the 450 NE 3-1/4" ought to be good in the 450 Dakota
as long as you add filler for that extra 10 grains of space.
His bullets were 480-grainers and the 450 NE has about zero throat.
Plenty of pressure easing in the 450 Dakota extra case capacity and modern throat:
0.300" length of 0.4590" diameter parallel-sided free-bore then 1*30' leade.
OK to go ahead and use 500-grainers in the 450 Dakota,
with Wright's 480-gr data for the 450 NE 3.25" with 26" barrels, F215 primer:

H4350 92.0 gr >>> 2125 fps
H4831sc 98 gr >>> 2000 fps

No fillers for the above, but I would pack it with foam wad or Dacron if used in the 450 Dakota.
You would probably get about same velocity with 500-grainers, or a little slower.

My load results with 25"-barreled 450 Dakota, Norma-made brass (measured H2O above), and F215 primer:

105.0 gr H4350 (no filler)
500-gr TSX >>> 2302 fps
Very like you got, but I switched to lighter bullet for ease on my walnut stock:

86.0 gr RL-15 and 5 grains Dacron filler (a traditional double rifle stylish load):
450-gr North Fork FP solid >>> 2279 fps
450-gr TSX >>> 2245 fps

100.0 gr RL-15 (no filler)
450-gr North Fork FP solid >>> 2594 fps
450-gr TSX >>> 2554 fps

Then I swithced to VARGET for temperature stability, no filler loads,
all with the 450-gr North Fork FP solids:
95.0 gr >>> 2412 fps
96.0 gr >>> 2440 fps
97.0 gr >>> 2475 fps
98.0 gr >>> 2493 fps
99.0 gr >>> 2520 fps

Those are all 5-yard chrono results, not corrected to MV, all are just 3-shot averages.

Then I realized, BY GOLLY !!!
I can do that with the .458 WM+.
And it is easy to load to slower velocity with the smaller case,
but I can still get the 450-grainers up to 2500 fps,
or 500-grainers up to 2300 fps.
The 450 Dakota does have its charm though.

I did check with the powder manufacturer (so as to get a second opinion on the advice I received as any sensible person would do in such a situation), regarding reduced loads of 2000-2100 fps with .460 Weatherby (because they had no reduced load data for .450 Dakota). I asked whether 85 grains of Varget or 85 grains of H4895 would be best with 500's in .460 Weatherby. They replied to use 85 grains of H4895 with 500's because of the testing they had done with reduced loads for that powder and the 60% rule. So, although I said yesterday that I would use Varget, upon further advice from the manufacturer, I will use 85 grains H4895 with 500's.

Very sensible, easier with no use of filler required,
though filler would probably make the reduced load in the 450 Dakota more uniform and accurate.
Please let us know what you get.
My 450 Dakota rifle seems to be the ballistic twin of yours.
You will save me some work.

I have used H4895 for the full spectrum in the .458 WM+.
85.0 grains is near max with a 400-grainer, heh-heh-heh.

105.0 grains is an old max load with H4895 and 500-grainer in the 460 WbyMag, 2478 fps.
95.0 grains, 2314 fps.
On that extrapolation 85.0 grains = 2150 fps.
60% of 105 is 63.0 grains minimum load for no filler.
Continuing the extrapolation,
75.0 grains might be just under 2000 fps.

I know you love the .458 Win and I have used the .450 a lot, but if I was able to get properly head stamped brass (because of international travel) and was doing it all again, I would use a blown out 2.5 inch long .404 Jeffery case necked up to .458.

A la .450 Vincent Short & G&A, etc.
I have seen Mr. Vincent toting one of those in Tanzania.
It worked well.
Cool.
I have fiddled with the .458/.416 Ruger, that is at least partially correct on the headstamp,
so would be your .458/404 Jeffery 2.5".

Might as well use the 404 case at 2.8” in 458, the 460 G&A. Duplicates 450 Rigby ballistics - 500 grain solid at 2400 fps - with 12-15 grains less powder. Fits very well in a Win M-70 with 3.6” magazine box. An advantage is that 4 cartridges fit in a modified magazine box which still fits flush with the stock and the 1-piece bottom metal.

I like my 450 Rigby in the Ruger RSM, but the Win M-70 460 G&A is somewhat handier.

Hard to choose which one to take on a hunt.

I would build it on a standard length action so that's why I would want a 2.5" case length, possibly 23" barrel, prefer velocity right at 2300 fps with a 500 grain softpoint, with an empty weight with scope at 10 lbs.

But RL-17 produces more energy than H4350 being a double-base powder (more nitroglycerin), though burn rate is listed as similar. That needs consideration.

Bob
www.bigbores.ca