Getting ready for a buff hunt in Zimbabwe I've been working to regulate my 375 with softs and solids. To get them printing to the same point of aim, I've got a spread of 9-1/2 grains of powder between the softs and solids. Is this too much of a spread on the powder and should I try someting else? I'm using Northfork 300 grain softs and Northfork 300 grain FPS.
My 458 Lott was nothing like my 375 on the regulation. What do you think?

As long as both loads are safe in your rifle, it doesn't matter what the difference is powder charges is between them.

George

What George said.....it's not uncommon at all for big bores....most notably doubles....to need a bit of difference in the solid vs soft charges to get them to shoot to same POA. Take a look sometime at a Woodleigh soft and solid side by side..and compare the crimp groove location and how much MORE of the solid will be going INTO the case.

Gary
DRSS
NRA Lifer
SCI
DSC

If they shoot to the same POI why whould you possibly care that the powder charge was different? Be happy, go hunting.-Rob

what is the velocity difference?

Jeffe- I haven't shot the loads over the chronograph yet. Probably should do that to see where I'm at. The chronograph seems to always depress me.
If I have a large seperation in velocities between the softs and solids, should I be that concerned? 9-1/2 grains just seemed like a lot after reading all the regulation reports where the grain spread was 1-2 grains.

Pegleg

Are you using more powder with the Softs or the Solids.

IMHO as long as the solids are doing @2200fps you will have all the penetration you need.

N E 450 No2- My loads are 71.0gr. for the 300 gr NF SP and 61.5gr. for the FPS by Northfork.
I guess I need to drag the chronograph out.

..Chronograph definately needed with such a big difference ........ Needed any way ..

71.0 and 61.5 grains of....????

Might be a teller there. With 300gr. TSX and Banded Solid, I've had great success with RL15, but didn't need different charges to make it shoot to the same point. Got lucky with this one. It shoots them all well so far.

David

Yes you do need to crono.

The NFFP's go through the barrel easier than the Softs.

quote:

Originally posted by gumboot458:
..Chronograph definately needed with such a big difference ........ Needed any way ..

9 grains difference, that's nearly 13% difference in charge, which is nonlinear, and would probably result in HUNDREDS of fps difference, leading to unexpected results

Of course I am the kind of guy that shoots ALL load developement loads over a chrono ...

Of course I am the kind of guy that shoots ALL load developement loads over a chrono ...

Not really doing the job if you don't. Chronos are cheap. You can get in one for less than $100 so there's really no excuse not to. I start out by loading 3 or 4 rounds, in 1 grain increments, with my top being the top book load. I shoot each through the chrony and check for pressure signs, if those give desired velocity and no pressure signs I load more for accuracy testing. Takes time, but insures safety and you know where you're at in velocity and what to do next time around.

David

9 1/2 grains is a huge spread for a .375.

Doesn't make sense to me.

And I couldn't imagine handloading without a chronograph.

Pegleg, I second the many recommendations above that you get a chronograph and work with it in your load development.

Then you may be able to figure out what's going on.

I've got a chronagraph and will drag it out this weekend. I'll post results at the first of the week. Thanks for the help and advise.

Pegleg,

What powder are you using? That might be an issue as well.

David

RL-15 is the powder I'm using. I've tried several powders but RL-15 gives me the results with the soft points I'm looking for.

You need to chronograph those loads for sure!!!

Here are some numbers to think about...from LD5. It doesn't list the NorthFork bullet line so I used 350gr Woodleighs, Soft and FMG. Only as a reference to show you how things can get out of hand quick.

Woodleigh 350 gr, SN and FMJ, 26" bbl, 375 H&H, 3.60" COAL, RL-15

SN---57.9/RL15, 2099 fs/ 40632 CUP
SN---66.4/RL15, ~2400 fs/~55000 CUP

FMJ---57.1/RL15, 2089 fs/ 40632 CUP
FMJ---66.4/RL15,~2475 fs/~55000 CUP

The same relationship held for Woodleigh 300gr SN and FMJ's...roughly 1500 CUP/grain change per grain of RL15 powder. IMR4831 ran 1100 CUP/gr.

The 9.5 gr difference fell inbetween the calclated numbers so I extrapolated but they are close.

You also didn't say WHICH bullet needed the additional powder.

You can see the pressures are more than I would want in a double.

I would also go with one of the IMR Extreme powders instead of RL15 as they ar MUCH less temperature sensitive...RL15 can get a bit bullish in the heat, but that is always argumentative. What works here in the Cascades doesn't necessarily work good in Zim, you will need to check the regulation over there. Maybe using factory ammo might be a possibly.

I use RL15, IMR/H 4350 and 4831 in my 375 H&H and 416 Taylor and also RL19. The difference in accuracy really depends on what bullet I'm shooting. I use RL15 to check accuracy but use the other powders in my hunting loads for the most part...there isn't enough difference in POI, group, or velocity to bother with but I like the temp range of the Extreme powders much better. I've also used Varget with 260 gr Noslers. It is a bit faster than RL15, but just as accurate so it's a tossup...I use whichever powder I have the most of when I use the Nos 260.

You might also try H4350 and H4831for the heavier bullets...They have slightly different burning rates than the IMR powders. Both brands have MUCH better pressure curves and fs/grain ranges and is are much less temp sensitive than RL15 and some Ball powders. Only about a 10KCUP pressure difference in roughly 9 grains, but does require more powder to equal the RL15 velocities, but you get a roughly 95% load.


Luck on your hunt.

Well I chronographed my loads.
300gr. Northfork SP with 71.0gr. of RL-15 averaged 2603fps over nine shots.
300gr. Northfork FPS with 61.5 gr. RL-15 averaged 2275fps over seven shots.

My Lott was easy with both 450gr. Softs and Cup Point Solids using 80.0gr of H4895.
Softs averaged 2360fps and the cup point solids averaged 2368. Both these bullets shoot to the same point of aim.

My 375 has me stumped as I have both softs and solids shooting to the same point of aim but the difference in FPS is over 300. Is this too much difference in velocity?

I would want more velocity for the solids. If you bump the charge up to get them in the 2400-2500fps range, how for off is the point of impact compared to the SPs? Keep in mind, buffalo are usually shot at less than 100 yards. An inch or two difference in point of impact would not bother me a bit. A buffalo is a huge target.

I would want at least 2400fps for a 300gr solid for buffalo. And, I would be happier with 2550. JMO.

Have you tried both bullets at 2,450 fps or thereabouts?

The .375 H&H has a reputation for somehow doing the impossible of shooting many different loads to the same POI. If they hit the target at the desired ranges, then it is good enough.

Still, I'd expect much less than 9.5 grains of difference.

I'm really puzzled by this. I use RL15 with 300's in my H&H as well, but with Barnes bullets. The following is my results and all loads shot into a 4" circle at 100yds:

300 TSX
RP Case
Fed 215
Lee Crimp
RL 15
70gr. 2599
71gr. 2611
72gr. 2665


300 Banded Solid
all other same
RL 15
70gr. 2598
71gr. 2630
72gr. 2668

As I said, all these went into 4" without me trying terribly hard. They also shoot really close to my 350gr. Woodleigh loads using H4350. I guess I'm just lucky, but this rifle is the easiest I own to load for. Bullet jump doesn't seem to matter, nor does primer or bullet selection. It does well with pretty much everything. Only change I have to make is for my whitetail load of 50gr. 5744 behind a 300gr. Hornady RN. That's just a bump on the elevation.

Maybe you should try another bullet combo. Maybe keep the NF soft and load some Barnes Solids if you can't get the NF solid to work. That'd be my suggestion. If you need a handful to try, send me a PM and I'll send you 10 or so to try out.

Hope this helps,

David Walker

quote:

Originally posted by Pegleg:
Well I chronographed my loads.
300gr. Northfork SP with 71.0gr. of RL-15 averaged 2603fps over nine shots.
300gr. Northfork FPS with 61.5 gr. RL-15 averaged 2275fps over seven shots.

My Lott was easy with both 450gr. Softs and Cup Point Solids using 80.0gr of H4895.
Softs averaged 2360fps and the cup point solids averaged 2368. Both these bullets shoot to the same point of aim.

My 375 has me stumped as I have both softs and solids shooting to the same point of aim but the difference in FPS is over 300. Is this too much difference in velocity?

I haven't used the 375 300gr NFFN's, but based on my experience with the 458 450gr NFFN's at 2220fps, the 2275fps you are getting should provide good performance. The bullets have the same SD, btw. 450NE No2 has had excellent results with the NFFN 450grainers at similar velocity as well.

But, I wouldn't have any qualms with 1" or so of seperation between POI between the bullets at 50yds. So, I'd pick up the FN load until I got that 1" seperation at 50yds and live happily ever after.

JPK

The Gunny Sargent that is the range master a the range I shoot at has seen me struggling with the softs and solids. He walked up to me and said if it was him he would just "de-tune" the soft load a little and start over with the solids. That sounds like what mrlexma is suggesting. That could be the answer.
JBrown- My point of impact with the solids pumped up to near 2500fps prints 3" high and 3" left of my soft point load. Any additional velocity with the solids pushes the bullet high left.
DWalker- A very generous offer and I appreciate it.
Seems like I have more work ahead. I appreciate all the advise!

Pegleg

Personally I would not worry about the 375's difference in velocity.

2275fs with the solid is plenty good IMHO. baised on 286gr Woodleigh Solids in my 9,3x74R going about 2200fps. One shot comletely through an elehants head, side brain at 5 yards.

Usually you will be shooting the solids at 100 yards or under, so their trajectory is not a problem. If the ressure of your softs is good, their increased velocity will help with longer shots if necessary.

I do not think I would want to shoot solids at 2600fps anyway.

My question is: Do you need solids?

I have not used Northfork 300 grain softs, but any proven soft should be fine. PH George Hoffman used only Swift A frame of other premium softs to back up his clients on buffalo.

Just a thought.

By the way, I am a big fan of solids.

Dave,

Your fretting over a non issue. Your good to go and remember the 375 is only the back up for the Lott. At this point just get some practice. Your load development is done. Do not go back and start over.

Mark