Hello,
I have been reloading for quite sometime, but only infrequently for the above caliber. I read various places that one should not full length resize the brass and the preferred method is to only necksize the brass for your particular rifle. I understand that the headspace is on the belt and not the shoulder and by doing full length resizing are you pushing the shoulder(what there is) back further than needed?? I have a large selection of brass/bullets/powder/primers, etc. for this round and in next couple weeks or so plan on shooting fair number of rounds and looking for some help here. All feedback much appreciated.

thanks,

martin

If the brass has all been shot in the same rifle, only neck sizing is necessary and would probably give better brass life. The brass will still probably stretch more than with other cases you may be used to so check regularly for incipient head separations (I run a paper clip with the tip bent to 90 degrees down the inside of the case to feel for a groove forming near the head).

Check case length regularly, too. It's an easy round to reload, but don't go overboard on the crimp or strange things can happen....

It doesn't really need any crimp at all if you have good neck tension. At least not at the range.

Strange things in the way of case issues or ballistics/trajectory?

I'm reading a lot of statements Martin, and I see question marks, but darned if I can decipher a discernible question. What's your question?

Question is should one full length resize 375HH or should one only neck size since only using one rifle/brass combination??

thanks,

martin

I adjust my FL sizing die to touch the shoulder after the first firing so that any growth in the case after repeated firings is pushed back to the once fired size.

You may have no choice other than to "partial full length size". The reason is that the .375 case has fairly significant taper and often times your chamber will be somewhat larger at the shoulder than is your sizing die. Even with the sizing die backed off to what would normally be the "neck sizing" position, the shoulder may be squeezed a little. This is not necessarily bad. "Partial full length" sizing generally helps make ammunition concentric and although it reduces the diameter of the shoulder it does not set it back. Therefore, you will still headspace on the shoulder but will work the brass a minimum amount and will have easy-chambering reloads.

The situation I am describing is what I have with my RCBS FL dies and a Sako chamber. Sakos usually don't have an overly generous chamber, either.

As with any full-power load, after several firings you may have to set your die to bump the shoulder back a minimal amount in order to prevent significant resistance to the bolt closing.

Lee makes the die you need, the Collet die, nuff said.

Partial neck size only. Watch trim length. If bolt becomes hard to close start a slow partial FL sizing or bumping shoulder back and checking incrementally in chamber for just firm bolt closure.

quote:

Originally posted by MFD:
Question is should one full length resize 375HH or should one only neck size since only using one rifle/brass combination??thanks,
martin

I'd say it comes down to two choices. It depends on what your intended use is.

It is conventional wisdom to full length resize either new or, once fired in your chamber, brass if you're hunting dangerous game. Personally, I do the same for all my big game hunting loads...I want them to chamber as easily and consistently as possible. I don't intend to scavenge around the sand or snow to retrieve a reloadable case while on safari. Nor do I care if each round headspaces on the belt.

I would also recommend the Lee Collet die for ammo used for paper targets. You'll get the longest case life when only resizing the neck. And since I don't know of any .375" ammo without a cannelure, I'd buy a Lee Factory Crimp die as well. Even though you don't need a crimp when working up loads shooting single shot, all your hunting loads should have a firm crimp. Crimping your final hunting loads might change the group size or point-of-aim of ammo worked up without crimping.

So it actually comes down to three choices; FL resize, neck resize, crimp or not. Good luck with that H&H mag.

Here's another thread on the .375 that's worth reading.

http://forums.accuratereloadin...991055601#5991055601

For cold weather , use a magnum rifle primer , for really cold weather and 4350 powder use a Fed 215 primer .......
Other than Brass availability I solved the case streaching by going to the 9.3x64 Brenneke ... I get 2650 fps with the 285 gr bullets and 2750fps with the 250 gr.bullets ....... 7 -10 reloads and still no need to trim the brass ...

Your objective is to headspace off the neck and not the belt. Other than that, your reloading is no different than that of any normal case. Just set your die to set the shoulder back by 0.002" or something similar, to ensure reliable cycling and minimal brass working.

OK, appreciate the feedback and believe I have the idea now. I do measure fired cases from the datum line w/ StoneyPoint-calipers set up on all my reloads to attempt to resize to closely match the chamber dimensions, and I do use Lee Factory Crimp dies on most calibers I load. I will be reloading/shooting the rifle for the next couple weeks and will work up various loads to chrono and see if I can come up with good loads using heavier bullets and one w/ lighter bullets. By the way, I do have a selection of Woodlieghs, either 300 or even 350's that I have no earthly use for and always looking for either 69,77 Sierra/MK or 168, 175
Sierra/MK. Again, thanks for the info from all.

martin

Martin,

If I can make a suggestion..."Grip it and Rip it".

I think you're over-thinking your first .375 loads. Good Lord knows that I've done the same thing with my .350 RMag and my .257 Bob. I have 12 different .257 bullets on the shelf...and yet I only need one.

One of the lessons I learned is to pick the bullet first, relative to the application at hand. For my .375 I've chosen two: the 300gr. Hornady IL Roundnose and the 270 gr. Barnes. With those two bullets I can pretty much cover everything and anything needed.

Bullets done, pick a powder: H4350 in my case (I have 4#).

Pick a primer: I have Rem 9.5 mags. Good enough.

Throw it together and see what sticks. I'll let you know in a week when I get my M1999 back from Jim Brockman.

The point of all this is that the .375, however inherently accurate as it might be, is, was, and was never meant to be a target rifle. Heck, the are plenty of rifles out there than fire smaller groups than the diameter of a single .375 bullet.

For me, my goal is reasonable accuracy, absolutely 100% reliability, and appropriate horsepower. Even if the M1999 was capable of 1/2 MOA accuracy, I doubt I'd bother to pursue it. If I got 1", I'd call it more than good enough.

I'd start with a FL resize, load 'em up, and see the results. Evaluate after the first loads and see if there is any real need to make a change. You never know - you might get lucky off the start and end up with a perfectly usable and effective load right off the bat.

PS: I've over thought wayyyyyy too many things. As Nike said, "Just Do It"...

Hello rnovi,

Sound advise. Yes, I tend to reload as it were a Palma rifle and most unlikely I or anyone else will shoot a 375 as much as one shoots a match type rifle. I have a lot of new brass and some once fired and will be going to the range middle of this week and will report as to the results. Would like to hear about yours when possible. I am shooting RSM and friend has Sako-375HH and both are working up loads.
Thanks for the feedback. Later,

martin

I'm using Hornady IL's at the range and 300 A Frames for hunting. (buff). I FL resize and get about nine cycles on Rem cases with max Hornady book loads and MOA accuracy. I crimp with the Redding seat/crimp die and that works very well. I always use IMR 4350 and Remington cases, and vary primers according to what's available. Lately that's been Winchester and CCI. The rifle's a Mod. 70 Safari Express. I love the rifle and am working up to a hunt in July, shooting 40 or more rounds per week.

Friends-

When reloading the .375 H&H, is it a given that you need to crimp?

I have never crimped reloaded rounds in my life. Not that that's a bad thing, I'll just have to adjust my mind set.

Thanks in advance.

I crimp because I always shoot four rounds at a time quickly and the crimp prevents bullets in the loaded cases in the mag from moving under recoil. I tried it the other way and got occasional bullet movement.

quote:

Originally posted by 30 Caliber Mag Fan:
Friends-

When reloading the .375 H&H, is it a given that you need to crimp?

I have never crimped reloaded rounds in my life. Not that that's a bad thing, I'll just have to adjust my mind set.

Thanks in advance.

It's a good question, and to be honest (since I'm just getting started with the .375 myself) I can only fall back onto the basics:

If it's got a cannelure and it's a heavy recoiling round, then crimp it. The exception I know: if it's in a tube mag, always crimp it!

So, yeah, I'm going to crimp my loads with the heavier 300gr. Hornady's.

Martin,
I am a big fan of the 375 H&H. YOu can load it up or down. I always use Federal 215 primers and my rifle seems to like H4831 SC. You can also do reduced loads with Accurate 5744. Email Accurate Powders and they will send you load information.

Nosler Accubonds work great on Plains Game and well as the venerable Nosler 300 grain Partiton.

quote:

Originally posted by 30 Caliber Mag Fan:
Friends-

When reloading the .375 H&H, is it a given that you need to crimp?

I have never crimped reloaded rounds in my life. Not that that's a bad thing, I'll just have to adjust my mind set.

Thanks in advance.

Mark: I don't crimp mine. Have found no necessity in doing so, and crimping limits your seating depth to wherever the cannelure is, which may or may not be the most accurate seating depth. Of course you don't have to crimp in the cannelure, provided you don't mind deforming the bullet's jacket on the bearing surface -- a practice that cannot be helpful to accuracy (and besides, provides little in the way of securing the bullet). While the .375 is hardly a benchrest round, the same principles apply to getting accurcy from it. Can you feature a benchrest shooter crimping his loads?

On my M70 375H&H I started my first reloads using the Remington factory load cases and the light Speer 235gr bullet. Then I moved up to Hornady 270gr SP, now for the last couple of years I have been loading Hornady 300gr BTSP.

For the 300 gr bullet I use:
Fed 215 primers
Hodgdon H4350 minimum load of 77gr and I get just over 2600fps.

My rifle seems to always shoot about 75 to 90 fps faster than the books say it should be getting, even the Rem factory loads shot this much faster than their cataloged velocity is supposed to be.

I have a lee factory crimp tool so I use it.
I like the way it tucks the case mouth into the crimp groove, makes for nice smoothly finish round.

I also use and like the Lee collet neck sizing die.

I think ctgs made by my Lee die really don't need to be crimped because I had to pull a few bullet once. I used a Hornady collet bullet puller tool and I really had to pull hard on the press handle to yank the bullets out.

The Lee full length sizing die moves the shoulder back about .006" I think that is too much for my rifle, over works the brass.

The next time I use it I will try putting a .005" spark plug feeler gauge between the shell holder and the die to see if I can reduce the amount of shoulder set back.

After firing and neck sizing I usually have to trim off about .006" of extra case length, this is one ctg that loves to stretch even when neck sized.

One BIG thing that I didn't see any one mention is to fill your magazine full and check that your ammo will feed. I had a friend who did all his range shooting 1 at a time. When he tried to reload from his magazine his rounds were to long.
With a dangerous game cartridge reliability is more important than small groups.
Bill

quote:

Originally posted by Bill Cooley:
One BIG thing that I didn't see any one mention is to fill your magazine full and check that your ammo will feed. I had a friend who did all his range shooting 1 at a time. When he tried to reload from his magazine his rounds were to long.
With a dangerous game cartridge reliability is more important than small groups.
Bill

Amen to that.

Anytime I go hunting, I cycle every single round through the magazine and action for reliability. I discovered at one point that my .35 Remington loads were "over-crimped", marginalizing the shoulder and making cycling very difficult. I dialed back the crimp die about 1/4 turn and fixed everything.

Good point.

You will have to determine just how accurate you need that rifle to be, and whether or not neck sizing and omitting the crimp will suit your needs.

I full length my brass each time, and crimp. With 67.5grs of IMR4064 and a Hornady 300gr RN crimped in the groove, it had a 3 shot group of .710 at 100yds., using a 4.5x scope.

That level of accuracy is much better than the game that rifle will be used on requires.

As was already stated, shoot with a full magazine. More than one floorplate has opened when fired dropping the rest of the rounds on the ground. Soilds can dent the magazine at the front and catch the bullet nose, preventing it from feeding. Bullets that arent crimped get shoved deeper in the case. Its better to find and fix these issues before it is needed.