Loading for a 375

62flint

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I am in the process of acquiring my first 375hh. I have been loading smaller bores for years up to 300wm. I think I am ok on powder, I have varget,rl15,imr and some others I see listed here as popular for people to use. primers I have a few thousand cci LR mag and federal Lr MAG , I need brass, bullets and dies. I use RCBS and will likely get a set of those dies unless I am persuaded other wise. I really like Barnes bullets, have had good luck with those in the past. But I am open to any thing that shoots good and works.
Brass, How many loads can you get out of good brass? I am thinking of trying to get 100-150 pieces to start. Is keeping the same brand of brass important with a 375?
How do most work up a load for a 375? I have done OCW and ladder tests before but being a shorter range cartridge I was just curious.
Thank you
 
for me i use Quick load. funny i am loading 20 shells now. For me i target a desired FPS within safe PSI. i am using IMR 4350. i have 300 grain Nosler Partitions given these are for my leopard hunt. At 73.5 grains i am below the max of 75 grains and i get my desired 2500 FPS. i will be shooting them tomorrow to see how they group. i have great confidence based on my experience they will be within MOA
 
Barnes .375 tsx bullets were on sale at midwayusa and might still be. Good practice fodder but I loved them for plains game as well. Enjoy the .375!
 
You like Barnes this was sent to help me with my 375R and working with H4350
my favorite powder ,


“”
If wanting to use a powder/bullet we do not have load data listed, you can use "other" (jacketed lead core or monolithic) bullet load data when loading a Barnes Bullet of equal (or close to) weight. Using data from HodgdonReloading.com or other sources/powder/bullet manufacturers. JUST BE SURE TO START AT THE MINIMUM STARTING LOAD and work up from there in half grain increments watching for signs of high pressure such as, a sticky (hard) bolt lift when ejecting the fired case, ejector mark on the case head stamp or flattened/leaky primers. Once you notice any of the high pressure signs then you will want to lower the charge about half a grain or so to where no high pressure signs are present, and that would technically be "YOUR" rifle's max load. The load data published by all of the companies is just a reference point/guideline to safely start out at the minimum charges. The MAX charge solely depends on your rifle's chamber, barrel length, powder lot #, brass case capacity/manufacturer and your environmental conditions. Using a website, loaddata.com’s “THE ULTIMATE RELOADING MANUAL” for the sole purpose of finding specific load data can be a huge time saver.



When loading a Barnes TSX, Tipped TSX or LRX bullet, your rifle may prefer a bullet jump of anywhere between .050” up to .250” or more. This distance off the lands (rifling), aka “jump” may be limited to the rifles throat length, magazine length and bullet length.

When selecting the cartridge overall length (COAL) we recommend starting with a minimum “jump” of .050” off the lands. This is the point where your load development should begin. You can then later test different seating depths and find a “sweet spot” that your particular firearm prefers. We suggest working in at least .025” increments as follows seating the bullet deeper to allow a further jump. Your test plan could look something like this:

1st group- .050” jump
2nd group- .075” jump
3rd group- .100” jump
4th group- .125” jump
5th group- .150“ jump
6th group- * see below

This length can be determined by using a “Stoney Point Gauge” or other methods/tools designed to determine your rifles best COAL. You do not have to seat the bullet at, or on one of the cannelure/pressure relief rings. The pressure relief rings have nothing to do with seating depth; ignore them! Remember, there are many factors that may control or limit the seating depth for your application. You may find that you need to start at around 0.150” off the lands and are not able to get any closer due to limiting factors including proper neck tension and magazine length.

*In rifles that have long throats you may be limited on how close you are able to get the bullet to the lands. In these instances, it is not uncommon to find the best accuracy with a jump of .200” or more.

This jump may possibly stay the same regardless of powder or charge weight within a given rifle. If preferred accuracy is not obtained, we certainly recommend trying another powder, for the powder type and charge greatly affects the overall accuracy of each individual firearm.

FYI- An accurate load requires a bullet with the proper consistent case neck tension which leads to more constant pressures and velocities.

Hodgdon and Hornady both have 270 gr “lead core” data but if both the above two processes are used you will have a fine reload developed before too long. As for the 235 gr TSX bullet use the 250 gr SFT AF bullet load data on the Hodgdon website. https://hodgdonreloading.com/rldc/?t=1 Remember to start low and work up.



Thank You
Alan Griffith
| Consumer Service
Barnes Bullets
IMG_0800.png
 
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I am in the process of acquiring my first 375hh. I have been loading smaller bores for years up to 300wm. I think I am ok on powder, I have varget,rl15,imr and some others I see listed here as popular for people to use. primers I have a few thousand cci LR mag and federal Lr MAG , I need brass, bullets and dies. I use RCBS and will likely get a set of those dies unless I am persuaded other wise. I really like Barnes bullets, have had good luck with those in the past. But I am open to any thing that shoots good and works.
Brass, How many loads can you get out of good brass? I am thinking of trying to get 100-150 pieces to start. Is keeping the same brand of brass important with a 375?
How do most work up a load for a 375? I have done OCW and ladder tests before but being a shorter range cartridge I was just curious.
Thank you

300gr Barnes TSX shoots exceptionally well from my Win 70 375 H&H (I load using IMR 4064 to about 2450 FPS).. I get very tight, consistent groups, and reliable feeding and extraction..

I use RCBS dies..

Ive got a mix of brass.. most is Remington.. but theres some federal in there as well as some winchester.. I havent seen a noticeable change in POI, accuracy, or reliability when switching between different cases..

I think 150 piece of brass will be enough to last you a very long time.. Ive got about 200.. I have no idea at this point how many loadings I can get from each piece, because I havent reached a point where any of the brass is showing any signs of stress or problems.. most of my brass has only been loaded twice.. but I do have some that have been loaded as many as 4x times so far..
 
Brass, How many loads can you get out of good brass? I am thinking of trying to get 100-150 pieces to start.
Brass life most likely depends on whether you like to hotrod your loads. 100-150 pieces will do ya.
Is keeping the same brand of brass important with a 375?
It is for some folks, not for others. As you already know, different brands are likely to have different case capacities.
How do most work up a load for a 375? I have done OCW and ladder tests before but being a shorter range cartridge I was just curious.
Thank you
No different than working up any other load. Just look at rule #1 on the wall - "there are the bold, and there are the old, but there 'aint too many old, bold handloaders around".

Most importantly, be sure you're having fun!
 
375 is inherently accurate, so loading can be fairly simple. The long taper on the case reduces stretch, so cases can last quite a while, but I would only use new (or maybe once fired) while hunting. As with all cartridges, staying with one brand of case, if available, reduces variables when questions arise. TSX is a great choice. RL15, Varget, and IMR4064 have all worked for me. Either primer. Best of luck!
 
I like to headspace belted cases on the shoulder to reduce case stretching and improve case life. Also, Reloading Technologies makes a die that will resize the case body just ahead of the belt, which further increases the useful life of belted cases.
I use RL15 or N-150 for the 375 H&H.
 
The 375 H&H is not a very good bench rest gun for shooting tiny groups, but it is very accurate and is capable of sub 1 moa or better groups. It is not a long range round but is plenty capable out to 300 yards. It is a thumper that with the right bullets is capable of the largest of game. It is not temperamental and I have found that it is easy to load for. Choose a bullet design and weight for your intended game animal and load them up. I like the 300 grain Swift A-Frames because they are a do all bullet. Barnes TSX or TTSX also work great. Cutting Edge bullets are also great for whatever your intended purposes are. https://cuttingedgebullets.com/catalogsearch/result/?q=375
I have found the best accuracy with RL-15 and Varget. I use RCBS dies. Hornady dies did not work well for me.
I have had good success with Norma brass which is now available from Raven Rock who advertises here on africahunting.com. I have 9 loadings on some of my Norma brass with no signs of case head separation.
https://ravenrocksprecision.com/norma-375-h-h-magnum-brass-50-ct/
One thing that is different with the 375 versus the 300's is that crimping the 375 is important to keep the bullets in the magazine from moving under recoil. So get a Lee factory crimp die which is the best for crimping. Since the case is crimped into the cannelure this limits the seating depth differences which reloaders who seek more and more accuracy use to fine tune loads. Also crimping effects accuracy as well. See my post about whether to crimp or not to crimp below.
I think you will love reloading for the 375. It is super fun.
 

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