Is 2300 fps too slow for 375 H&H 300 gr solid?

[KTMpilot]

Yet another thread about muzzle velocity, please forgive me. I am asking for some advice, and please if I may state up front: I am not looking for alternate bullet or propellant suggestions, I am like many reloaders worldwide at the moment bound to what I can get reliably and regularly at the moment where I live, so I am asking for some inputs about what I have to work with, as follows:

I need a new load for my 375 H&H P.H. backup rifle, and what I have loaded is this-

24" Savage 116 rifle; 1:12 twist
Impala Round Nose PH-Range Non-expanding Solids, 300 gr; BC: 0.350
63,1 gr IMR 4350
100,1% Case Fill Ratio
Amount of Propellant Burnt: 93.98%
Quickload muzzle velocity: 2294 fps

I have always followed an old rule of thumb for 375 H&H of 300 gr at 2500 fps, but in this case, the maximum I can get is 2300 fps, limited by case capacity. It may be that the BC of the round nose solids is just prohibitive of getting 2500 fps of course too. I have not yet tried a compressed load, and have not at yet chrony'ed the load, nor done any wet pack or other penetration tests.

So my question, and I know it is a "how long is a piece of string" question, is if 2300 fps is maybe just too slow for penetration on anything that can trample, can anyone maybe say out of hand?

 

[Luvthunt]

Well, not an expert but a heavy reader with a few trips to Africa.
The documented and supported vel by many people is 2150 is adequate for the needed penetration on thick skinned animals. This was established in 1897/8 with the 450NE.
As always shot placement counts!!

By the way there were cartridges that did not achieve the published velocity but that only muddies the water.

 

[Green Chile]

Put those bullets in the right spot and it will kill anything in Africa. They won't bounce off!

 

[shootist~]

Going over 100% case capacity (compressed load) is not an issue so long as you are under max pressure. Is there something different with the 375 H&H?

 

[Jefferry404]

cannot help with the 2300fps question but can with QuickLoad. For all my load development, I first calibrate QL to a published load by fitting the Weighting Factor WF and Burning Rate Factor BA for both the min load and max load. Then I use the calibrated powder min or max for my new load depending which charge weight is closer. The Hodgdon Reloading website (https://hodgdonreloading.com/rldc) is a great resource with pressure data for all loads (per Hodgdon the pressure data is from measurements). I then shoot 3 rounds to measure velocity and re-calibrate the BA factor to match the velocity. Then make the load.

As an example, below is QL fitted to the IMR 4350 powder per Hodgdon data. I would then use the fitted powder to develop a load for the Impala Bullet.

 

[sgt_zim]

A 300 gr 375 H&H at 2300 fps is ordinary 9.3x62 with 286 gr territory. I have a whopping 1 cape buffalo under my belt so take my utterings with a grain of salt; with my 9.3x62, I wouldn't want to take a strong quartering-to shot with my load, and my load is nearly 2500 fps with A Frames. Solids are a different matter though, right?

 

[Joker12]

Have you chronographed that load? Anything that any computer spits out is only a guess.

 

[KTMpilot]

cannot help with the 2300fps question but can with QuickLoad. For all my load development, I first calibrate QL to a published load by fitting the Weighting Factor WF and Burning Rate Factor BA for both the min load and max load. Then I use the calibrated powder min or max for my new load depending which charge weight is closer. The Hodgdon Reloading website (https://hodgdonreloading.com/rldc) is a great resource with pressure data for all loads (per Hodgdon the pressure data is from measurements). I then shoot 3 rounds to measure velocity and re-calibrate the BA factor to match the velocity. Then make the load.

As an example, below is QL fitted to the IMR 4350 powder per Hodgdon data. I would then use the fitted powder to develop a load for the Impala Bullet.
View attachment 640438

Thanks very much, I will play around with that on Quickload, I think I may be achieving more or less the same effect with a trick I read somewhere long ago, namely adjusting the "Ratio of Specific Heats" value up or down for a load until the computed muzzle velocity equals the actual 5-shot chronographed average for a load.

 

[KTMpilot]

A 300 gr 375 H&H at 2300 fps is ordinary 9.3x62 with 286 gr territory. I have a whopping 1 cape buffalo under my belt so take my utterings with a grain of salt; with my 9.3x62, I wouldn't want to take a strong quartering-to shot with my load, and my load is nearly 2500 fps with A Frames. Solids are a different matter though, right?

Thanks, I wouldn't hunt myself with this load, it is a backup load for putting metal into something when things have gone pear-shaped. When hunting myself with this rifle, I use premium bonded solid shank expanding soft's with a lower BC and don't struggle to get the speed closer to 2500 fps.

 

[KTMpilot]

Have you chronographed that load? Anything that any computer spits out is only a guess.

No not yet, as I did say in my OP, but for what it is worth I will post back here when have chrony'ed the load

 

[pilar]

No not yet, as I did say in my OP, but for what it is worth I will post back here when have chrony'ed the load

I think you will be close to your original FPS with 63gr 4350 ( and should be fine for emergency use)
KISS loading
Our 375h&h load is simple 75gr 4350 = 2500fps
375Ruger is 80.0 4350
This is with 300gr Speer GS tungsten core solids and virtually everything else 235gr - 300gr

 

[Jefferry404]

just to complete the exercise, here is the expected velocity for your load (used the barnes fitted minimum charge weight data) and lets see how compares to your measured velocity. I had to dig around for the 300gn bullet length, 1.457" and used 3.41" for the OAL (derived from your data).
If the lengths are different, let me know and will update. Thanks
Steve

 

[KTMpilot]

Thanks, here is my Quickload calculation using actual bullet length, case length, COAL for my magazine dimensions, actual case H20 capacity, and barrel length. I will post back when I have chronograph results. Thanks for your inputs.

 

[Jefferry404]

thanks for the info. I am always looking for real world data other than my own. Please note the shot start pressure of 5076psi. Due to the bullet construction, I would use what QL has. I have feedback from the QL engineer regarding Swift bullet that Mr Broemel has labs measure this for him.
Attached is the QL using your info and fitted from the Hodgdon published data above with the higher Shot pressure.
Please feedback the velocity measurements. thanks
Steve

 

[Puddle]

So, PH backup load? Say, 10 - 20 yards max distances? (and less).
Sounds like you're good to go as far as MV.

The only proviso I'd have is rounds in the magazine all day during the hot months that are 100% load density with a temp-sensitive powder.

 

[375Fox]

I’d be more concerned about the rifle than the ammunition.

 

[uplander01]

It will work just fine

 

[Green Chile]

I run my 300 TSX at about 2400...but if it hits them at 2300 it wouldn't make any difference visible to me. I already get pass throughs on most hits.

 

[Rare Breed]

Put those bullets in the right spot and it will kill anything in Africa. They won't bounce off!

I think you are just fine! My personal experience is I don’t want to go over 103% compressed loads though some AH friends go as high as 106% just not me

 

[Green Chile]

For sure...it doesn't need it. Those bullets will kill easily.