Went to the range yesterday with the 375 Alaskan & chrono to see how much I could get out of her using Varget. I know there's better powders out there for the 375, but I like the idea of using one powder (with great success) over most of my rifles (223 through 458 Lott). This testing was just for finding max loads, not for accuracy, but all loads went into about a verticle 1" line at 50yds. MY GOAL WAS TO GET 2500 FPS. These loads were in MY rifle, with MY componets - your on your own if you want to try these. The latest Hornady loading manual is pretty good for powder selections for the 375 & 416 Rugers, so I started from there:

300gr Barnes TSX - Varget Powder - COAL @ 3.315" - Medium crimp at "top" ring - CCI Large Rifle Magnum Primers

1. 60.1 gr @ 2235 fps
2. 64.1 gr @ 2268 fps
3. 66.1 gr @ 2373 fps
4. 68.1 gr @ 2413 fps
5. 69.1 gr @ 2470 fps **HORNADY MAX LOAD**
6. 69.6 gr @ 2479 fps
7. 70.1 gr @ 2464 fps
8. 70.6 gr @ 2485 fps
9. 71.0 gr @ 2526 fps **NOSLER MAX LOAD**
10. 71.3 gr @ 2535 fps
11. 71.6 gr @ 2531 fps
12. 71.8 gr @ 2520 fps

I did not experience any pressure signs with any of the loads. Cases and primmers appeared fine with no bolt stick. The charges over the 71.0gr Nosler max did not appear to have any additional velocity advantage (although they were only 0.3gr additional). I was told near max loads kind of level off before pressures get excessive, so I'm going to stop at my goal of greater than 2500 fps - I don't like dancing with the devil!!!!

Try a slower burning powder such as MRP or Re22 behind that 300 gr. bullet. Take it up until you see pressure signs. I bet you do much better. AIU

he only wants to use Varget. Then that is about all you get. Not bad, but go to Re15 or Norma 203B or similar powder and you will get 2600-2700 fps depending on whether you have a 20" or a 26" barrel...

Re22/MRP are too slow powders for this 375..

buffalo, have you tried MRP in the 375 Ruger with 300 gr. bullets? AIU

H4350 Extreme is excellent in both the .375 H&H and the .375 Weatherby, giving top velocities within pressure limits for both with the 300-grain bullets.

The .375 Ruger case capacity falling between those two makes it work there too.

RL-15 and Varget (as you have shown) are good, but better with lighter bullets than 300-grainers, in anything greater than the .375 H&H case capacity.

MRP and RL-22 should be tops with the 350-grain bullets in the .375 Ruger. With my .375 Weatherby, over 2600 fps with 350-grainers is within pressure limits.

RL-17 is said to be amazing in the .375 H&H. Might be even more so in the .375 Ruger.
You should load that one next, so you can give us a report on it.

TSX bullets are long for weight, and will not give the top 300-grain velocities that can be had with Sierra, Nosler, and Hornady bullets.
Keep in mind the intrusion on case capacity.

quote:

Originally posted by Ackley Improved User:
buffalo, have you tried MRP in the 375 Ruger with 300 gr. bullets? AIU

No always thought it was too slow... But maybe I should give it a try..
Will also try Norma URP (about the same as RL-17) soon.
Thanks guys..

I've been reloading for 20+ years, but I am fairly new to the big bores. Is there any difference in closing in on max loads with the cannons versus the pea shooters? A few newby questions for those of you who do play around with cannon max levels:

Is bolt stick and primmer appearance good indicators for pressure signs?

How many grains or tenths of grain powder do use in each step up when approaching maximum levels?

Is leveling off of velocity still a good indicator of approaching limits?

I'm shooting currently in 20 deg weather with Varget (which doesn't seem to change in different temps), but could there be an issue in warmer weather - especially if I try another powder?

I am genuinely interested here.

If chasing velocity is the goal - why not move to a bigger case? .375 H&H, .375 Wea,.375 Ultra mag?

Each to his own and all.. But I am curious as to the reasoning.

quote:

If chasing velocity is the goal - why not move to a bigger case? .375 H&H, .375 Wea,.375 Ultra mag?

Each to his own and all.. But I am curious as to the reasoning.

Not chasing velocity just finding out the safe limits of my rifle & ammunition. That Ruger case has much more room in it, even at my current max loads with Varget, which shows (as many have agreed) that a different powder would probably produce higher velocities @ the same or less pressure.

I might be willing to try another powder someday, but a 300gr TSX @ 2500 fps with excellent accuracy is more than enough..... for now.

(The Ruger is bigger than the H&H)

I definitely agree with RIP's assessment of H4350, RL-15 and RL-19...I have a few velo numbers using those powders with Nosler 260 PT's, Horn 270 and 300 gr and there was a difference of about 150 fs beteen the slower powders and the faster RL-15 with all the bullet weights...~2800fs with the 260 and H4350, one round only and ~2650fs with RL-15, one round only...~2650 with the Horn 300 gr, H4350, 2 rounds only...not much of a test but a good starting point.

None of my software programs listed powders in the 4350 burn rate for some strange reason and only Hodgdon's site had a listing of the various powders including the slower ones, but it was a good list including pressures, but not a lot of bullet brands.

It required about 10 gr more of the slower powders and got closer to an optimum fill per bullet weight and this was just beginning loads, no where near an optimized load per bullet weight.

I'll start a comparison between my 21" 375 H&H and the 26" 375JDJ I'm just about to start work on and I sure hope the information about RL-17 pans out...that is a fantastic powder so far with 7-08.

I will throat the JDJ for the Hornady 270 at ~3.22", bullet base at case neck botton - 0.300" seat depth, ~65 gr H2O, for maximun net case volume of ~58.6 gr H2O, in a Savage threaded barrel.

I wonder if anyone has tried Superformance in any of the larger cases yet?

Luck

I use mostly H4350 in the NEW KING of the .375's....

But I tried RL-17 and 300gr Nosler Accubonds.

2700+fps was the norm, and good accuracy.

I have a 375 H&H Ackley Improved (375 Weatherby). It has 105 grs. H20 capacity, compared to 99 grs. for the 375 Ruger and 96 grs. for the 375 H&H. I use a 26.5" barrel, and I'm getting 2925 fps (Oehler) with 300 Sierra GKs or Hornady BTs using ~95 grs of MRP and with very good case life. I use 89 grs. of N204 with 300 gr. Failsafe bullets to get 2875 to 2900 fps fps and with very good case life. The latter is my Cape Buffalo load. I'd suggest starting with MRP and use it, if you achieve your desired velocity. If not, then I'd move to N204, which will very likely achieve the velocity you want, but at a somewhat higher PSI. I predict the load wil be compressed, but this has never casued a probem for me. Regards, AIU

I'm using 78g of Varget behind the 340g Woodleigh in my 416 Ruger and I use 375 Ruger brass,

Regards S&F

I want to point up a few interesting factors concerning the "VS" stuff between the 375 Ruger and the 375 H&H...NOT to get anyone stirred up or cranky...just some information FWIW...NO BETTER/BEST/BS.

I've been crunching some numbers between my anticipated 375-444 Marlin project, the Ruger, H&H and RUM offerings to arrive at an optimum case volume for the different cases and comparing velocities between 21" and 26" bbl lengths.

When I adjusted CASE VOLUMES by picking a seating depth of ~0.300", to the neck bottom on ALL cases reguardless of advertised max cartridge OAL's and picking a Hornady 270 gr bullet as a "standard" across the board I came up with a few interesting(at least to me) facts.

The Ruger had a NET volume of ~89 gr H2O at a OAL of 3.55"....just right for my Savage 110.

The H&H had a NET volume of ~87 gr H2O BUT at a OAL of 3.84"...WELL over the mag length for my Savage and closer to the mag length of a Weatherby or commercial Brevex Mauser magnum or PH action...a NET volume of 79 gr H20 at 3.55" COL...12% less than the Ruger. All these percentages stacking up or down can make life happy or miserable, can't they.

They both had almost identical velocities and pressures with H4831...2835fs for the H&H and 2856fs for the Ruger at very near the same pressures, 53.8KCUP plus or minus a bit.

In this scenario the Ruger wins out by virtue of an optimized case volume at a OAL that works in most receivers...(ust what Ruger's designers understood, and why the Ruger case is such a great one)...that produces high velocity at a reasonable pressure.

This ISN'T any kind of denigration against the H&H...if you want to jump up and down go talk to the mirror...it's just interesting to me information that can be used or not...it's YOUR choice.

For those with more interest and can do a search...there is a QL analysis for a 24" Ruger, 300 gr TSX, 3.34" COL at 65KPSI that makes for excellent reading. I wonder just what the numbers would be if a COL of 3.55" was used? I need to get QL and quit mucking about with LD...I'm finding WAY to many mistakes.

But what was more intesting and obvious and jumped out at me was the Ruger...IF loaded out beyond the ~3.31" Hornady 270 SP spec to 3.55"(throated if needed), 24" bbl(~2819 fs Load from a Disk) would come VERY close to the Hodgdon's website listing of 2922fs for the 375 RUM at the SAME OAL...3.55"...with ~14% less powder...89.6 gr H4831 against 104. It also points up the fact that once the point of diminishing returns is hit, you pay throught the nose for any additional gains.

This also told me that by increasing the pressures so BOTH the Ruger and the RUM were at 65KPSI, both could increase their velocities by a bit and still be perfectly safe, and the RUM might better be served using with a 350 gr bullet.

I think a whole lot of the pissing contests comes about by NOT comparing NET USABLE VOLUMES, there was a range between 79 and 98 gr H2O between the different COL's and the different cases, when it comes to favorite loads and cartridges. We all get worked up and forget about all the nuances that can be utilized to optimize our favorite shooters....it just takes understanding of the factors and a willingness to LEARN from others experiences and those experiences just being different and not necessarily a "good/bad", "you're a dumazzz" thing.

I think I just dumped my 375-444 Marlin project in favor of a 26" 375 Ruger barrel. I will gain an addition 200 fs or more over my present 21" H&H using the same bullet and using a 3.55" COL. But I will even have enough barrel length to do an 18" stub barrel 375-444 M for a NEF(if those high dollar dies keep bugging me)...WITH a MB so even a puny like me won't mind.

Luck

Agreed the 375 Ruger has more useable case capacity in the std '06-type action compared tothe standard 375 H&H, and thus, IMO is superior to the H&H. Yet, the 375 H&H Ackley Improved (105 grs of H2O) with powder compression can prduce super results as noted above - essentially at the PSI limits of the case. It can also shoot 375 H&H or Weatherby, if you should lose your ammo in transit. Regards, AIU

Absolutely right AIU...the net volume of the H&H AI would be about 89 gr H20 at 3.55" and about 97 at 3.80", 0.300" seat depth...very close to the 375 RUM at 3.55" seat depth for the 270 Horn.

The extra 5-10 gr of powder translates to a higher velocity...but the most important thing is that the higher velocity translates into a very high additional energy...and ENERGY is what we are all after.

The additional muzzle energy from ~2700 fs, 375 Ruger, 270 Horn, 3.55" COL, to ~3000fs, maxed out 375 RUM/375 H&H IMP, 270 Horn, 3.55" COL, is on the order of 1000 ft lbs.

THAT'S what I'm talking about!!!!

All you gotta do is optimize/maximize the various parameters and it's almost like stepping UP a case size or a caliber. Neat isn't it.

Luck