I blame all of you...

[BRICKBURN]

Ok, not really your fault. I worked too darn hard this year and got myself a present. I deserve it.

I just picked up a brand spanking new CZ550 in .375H&H (Standard Safari)
Holding 5 down in that magazine makes me quite happy.
Just something about that number that makes me feel better.

With it, I grabbed a box of winchester ammo, just to put bullets through the barrel. This weekend.

I then started to scramble to find bullets, powder, dies, recipes etc.
ZERO supplies in town.
I have ordered from across the country.
The courier is bring 50 Brass, 2 pounds of powder and 2 boxes of Barnes 250 grain TTSX are on the way.
A full die set is on the plane coming back on Friday from Ontario.

The research started:

On AH: Phil was working this one up a while ago and did some extrapolating on it.

I emailed Ty at Barnes directly and asked what the reloading recipe was for these bullets. This is what I got back:

"We are simply suggesting that you split the difference between the 235gr and 270gr TSX data for the 250gr TTSX bullets. See attached"

Seems Phil was right to do what he was up to.

Some other findings:
Hodgdon doesn't even recommend over 69gr of H4895 with a 250gr bullet.

Another one:
Barnes 250gn TTSX / Reloader 15 / Fed215 / Nosler Brass / NO crimp
73.5gn - avg 2695fps
74.5gn - avg 2745fps
75.5gn - avg 2785fps
76.5gn - avg 2801fps
77gn - avg 2833fps


And then some lunatic from Namibia (DOC!) suggested this recipe:

"I found that my 550 .375 likes a jump-start..! I get sub MOA at 100 and 200 with Norma brass, 250gr Sierra GK's (my favorite bullet) and 65 gr of Somchem S 335. Velocity around 2560 fps."

Apparently IMR 4320 is an equivalent to the Somchem.



I'll be trying the IMR 4895 as suggested by Barnes and extrapolating between the 235 at 270 grain bullets and come up with something that works. I can only hope the CZ likes the TTSX as much as my other rifles. I'll see how it goes.
thanks for everyone contributing and putting the information out there to be found.


Anyone used GS CUSTOM Solids. 300 Grain??
Getting solids up here is impossible.

 

[Royal27]

Nice....

 

[K-man]

Yes it's my fault. You had to spend too much time editing my posts and checking fer spelling airors. You deserve it! Good luck with it and shoot straight!

 

[sestoppelman]

You mean you didn't already have a .375?!?!?!?! IMR4064 is the classic powder for less than full bore stuff. The load doc listed is just a 9.3x62 equivalent load. Do you intend it as such?

 

[James.Grage]

New winter project.

Remember cold weather has an effect on your powder bullet performance...

 

[PHOENIX PHIL]

Ok, not really your fault. I worked too darn hard this year and got myself a present. I deserve it.

I just picked up a brand spanking new CZ550 in .375H&H (Standard Safari)
Holding 5 down in that magazine makes me quite happy.
Just something about that number that makes me feel better.

With it, I grabbed a box of winchester ammo, just to put bullets through the barrel. This weekend.

I then started to scramble to find bullets, powder, dies, recipes etc.
ZERO supplies in town.
I have ordered from across the country.
The courier is bring 50 Brass, 2 pounds of powder and 2 boxes of Barnes 250 grain TTSX are on the way.
A full die set is on the plane coming back on Friday from Ontario.

The research started:

On AH: Phil was working this one up a while ago and did some extrapolating on it.

I emailed Ty at Barnes directly and asked what the reloading recipe was for these bullets. This is what I got back:

"We are simply suggesting that you split the difference between the 235gr and 270gr TSX data for the 250gr TTSX bullets. See attached"

Seems Phil was right to do what he was up to.

Some other findings:
Hodgdon doesn't even recommend over 69gr of H4895 with a 250gr bullet.


I'll be trying the IMR 4895 as suggested by Barnes and extrapolating between the 235 at 270 grain bullets and come up with something that works. I can only hope the CZ likes the TTSX as much as my other rifles. I'll see how it goes.
thanks for everyone contributing and putting the information out there to be found.

You are correct sir with me working those 250gr TTSX's and the method employed. What you may not remember is that I was intending to come up with some safe starting loads for H4895. Checked my math twice, started what I thought was low. It wasn't, and I had pressure signs immediately.

I don't have my Barnes manual in front of me, probably could find it. But after a recent move, I still have yet to get my reloading equipment set up (that will start to change in literally just a few minutes). So I don't remember the numbers.

My 250gr NF's were being pushed by roughly 72gr of H4895. I could go higher than that in Varget, but everything pointed to higher pressure in Varget to get the same velocity at the H4895. You should easily be able to get 2800fps plus with either IMR or Hodgdon 4895.

But.....work up slowly to it. I would go so far as to say use the min load for the 270gr Barnes. Load up just two at a time and shoot them over the chrony. Watch the copper build up at the muzzle too.

These were fast and dang accurate in my M70 until roughly 10 shots down a clean barrel. The accuracy would go down from there quite quickly. The end of the barrel looked like a brand new penny.

Congrats on the new rifle!

EDIT: I just looked back at the RL15 loads you listed in your o.p. I think Barnes may be selling themselves short here. Those upper loads should be well over 2800fps based off my experience with Varget, RL15's twin. Also, it was somewhere around 76gr or so that I was getting pressure signs.

 

[BRICKBURN]

You mean you didn't already have a .375?!?!?!?! IMR4064 is the classic powder for less than full bore stuff. The load doc listed is just a 9.3x62 equivalent load. Do you intend it as such?

Ses, I am just searching. I am going to use the Barnes recipe to start out and see what I can learn from there.

This is the biggest gun in the armada so far!

 

[BRICKBURN]

………..
But.....work up slowly to it. I would go so far as to say use the min load for the 270gr Barnes. ……....

I am a chicken. I will start low and as suggested by Barnes move up 2% per attempt.
No desire to experience bad things.

 

[BRICKBURN]

New winter project.

Remember cold weather has an effect on your powder bullet performance...

The first test for this is scheduled for an Elk in January. Should not be to cold. -30C.

 

[sestoppelman]

Phil, I always thought R15 and Varget were pretty much the same as well, but a recent batch has shown to me, at least in some applications, not to be true anymore, with R15 now being considerably slower than it once was. Maybe it was just one batch I don't know. I found this in particular in my .405 Win when working up a load for my safari. I have used both for years and was really surprised when I ran a bunch of test loads over my chrono, when the R15 loads were coming in over 100fps or so slower than expected and much slower than Varget with the same charge. Varget also is somewhat slower than either 4895 but again it can depend on the application. This is something a lot of reloaders don't know - powder burn rate is dependent upon the application. The charts are just a general guide. I settled on Varget for my .405 load both for speed and accuracy.

 

[bluey]

good stuff bricko .
I havnt had much succsess reloading the big banger yet ,waiting for the barnes projectiles was the biggest down fall .
I love the way guys so caually say you either ordered them or walked in the shop and got them straight off the shelf.....
one word of warning , DONT LEND THE GUN TO YOUR KIDS , OR YOU WILL SOON FORGET WHAT IT LOOKS LIKE ......
have a ball with it ,mate......

 

[PHOENIX PHIL]

Phil, I always thought R15 and Varget were pretty much the same as well, but a recent batch has shown to me, at least in some applications, not to be true anymore, with R15 now being considerably slower than it once was. Maybe it was just one batch I don't know. I found this in particular in my .405 Win when working up a load for my safari. I have used both for years and was really surprised when I ran a bunch of test loads over my chrono, when the R15 loads were coming in over 100fps or so slower than expected and much slower than Varget with the same charge. Varget also is somewhat slower than either 4895 but again it can depend on the application. This is something a lot of reloaders don't know - powder burn rate is dependent upon the application. The charts are just a general guide. I settled on Varget for my .405 load both for speed and accuracy.

Interesting about the RL15. I found it to be quite temp sensitive and have gone away from it in preference of the Hodgdon Extreme line. No doubt 4895 is quite a bit faster. I just looked up my 250gr NF loads for my .375. 72.8gr of H4895 gave 2850 fps, I needed 76gr of Varget to get the same. But the 76gr Varget load left me with just a bit of a sticky bolt. I was able to go above the 72.8gr H4895 load without the pressure signs, but accuracy started to suffer.

 

[sestoppelman]

All guns are different of course. In my .375 I just always used the slower powders, namely IMR 4350 and IMR 4831. But all I used were 300gr bullets. I used for my main load 82grs of the 4831 to drive a 300gr Nosler Part to nearly 2600fps. But this was in the days when the lightest bullet around for the .375 was 270grs, except for the silly little 235 Speer. I haven't hunted that rifle, a Whitworth Express, since '96. I keep thinking what a great rifle it would be to take to Central Africa for LD eland and bongo! Oh man..... Okay, done jacking this thread.

 

[BRICKBURN]

good stuff bricko .
I havnt had much succsess reloading the big banger yet ,waiting for the barnes projectiles was the biggest down fall .
I love the way guys so caually say you either ordered them or walked in the shop and got them straight off the shelf.....
one word of warning , DONT LEND THE GUN TO YOUR KIDS , OR YOU WILL SOON FORGET WHAT IT LOOKS LIKE ......
have a ball with it ,mate......

We are lucky. Got a license. Walk in, pay for it, walk out.
I am going to make some noise this weekend!
I can hear the shots echoing up the canyon now!

 

[BRICKBURN]

………….. I keep thinking what a great rifle it would be to take to Central Africa for LD eland and bongo! Oh man..... …...

Me tooooo!

 

[sestoppelman]

Wayne, I had my newest CZ to the range again today. Its a 90's vintage 550 Lux (or Medium) in 7x57. 24" barrel with sights, Euro style stock. It shoots quite well and I am digging it. Good luck with the three seven five. Enjoy the blast!

 

[adgunner]

Wayne, just bought the exact same gun about a month ago. Ammo is hard to find but have fed through mine both remington 270 grain SP and Remington 300 grain Swift A-frame. Both loads seem to get me about 1.5 inch groups. Will be watching your load development with interest as i detest being at the mercy of buying what i can find locally. Have you thought about optics yet? Good luck on the elk! Hope to get mine out on some cull deer in the early spring.

 

[BRICKBURN]

For now I am just going to use the express sights.

 

[BRICKBURN]

Wayne, I had my newest CZ to the range again today. Its a 90's vintage 550 Lux (or Medium) in 7x57. 24" barrel with sights, Euro style stock. It shoots quite well and I am digging it. Good luck with the three seven five. Enjoy the blast!

I have two buddies that just can't wait to see what it feels like. This afternoon might just be the inaugural event.

 

[Christina Nyczepir]

I love my new CZ 550 .375 H&H. I call it my big girl gun! I'm so proud of her that I even had a beautiful leather gun sling custom made for her including zebra skin. My original plan was to use it to hunt eland this past July. What I loved, was all the recommendations the guys were making on what ammo to use. .375 H&H just isn't all that easy to come by here in the states. So not like you have a smorgasbord of options to choose from. The only ammo my guy at my favorite gun store could come by, and had to specially order, was Federal brand, 300 grain soft point. This last outfitter only allowed soft point ammo. I'm sure you'll look better than I did firing yours for the first time, Wayne. LOL!