375 RUM and the 260 Accubond...

[Kennibear]

Doublezranch

Mrultramag pointed out the Real Guns website and I too go there for loads. Real Guns is where I found the 375 Ruger and made a decision to acquire one. His loads are not as extensive as some but they are reasonable selections of components. He uses some bullets like North Fork that you don't see very much.

After my last post I dug up the latest Nosler manual and see they recommend 96grs of IMR 4350 as a top load with their 260gr AB for the 375 RUM. Interpolating that data point, change my recommended top load for Superformance to 100grs.

Lefty7mmstw points out that Superformance can fall off the charts real quick and that is very true. It is not for every combination but when it works it really works well.

Smokeless Powder was real alchemy to me when I started reloading in 1971 so I have always searched out every piece of info and data I can find on the subject. It really is rocket science - solid fuel rockets though. Handloader Magazine covers one powder every issue, sometimes two and that is a great source for knowledge. If you aren't intimidated by the basic science it all fits together in the ol' brain. Lots of info out there today, thank God!

 

[Doublezranch]

Like all of you, I have a reloading room full of powder that I thought would work great and then fell off the map. I will try Superformance and see how well it works. The best quality of reloading is time. If something doesn't work, just wait, there are many others trying new things with powder/bullet combos that might use up that powder that didn't work previously.

I'm going to try a couple of things. My bullet choices are 260 Accubond and the 320 CEB's. I am going to tinker with the accubonds cause they are much cheaper than CEB's. However, once I get my reciepe dead to rights with the 260...I will then have a much better idea of the animal I'm dealing with. My ultimate goal for this RUM is ELR. But first, since the factory barrel is new, I'm going to have fun hunting with it. Then transfermation begins. Thanks to all who have weighed in with information. I will use all of it in some way, type or form.

Jayson

 

[Kennibear]

Jayson

The only down side to 3/8" bore rifles for ELR is a drought of high BC bullets. 7mm, 308, and 338cal have a great selection of very high (>0.600 BC) bullets to choose from. Also, most of the 375 cal bullets are of a very stout construction, not the best when velocity drops to <1800fps. The bullets for 375 will hammer a big ol' bear and go clean through his tough body but that makes them too tough for way out there. I see the limit as about 1000yrds for the bullets we have and that's not close range shooting by any stretch but most ELR is defined as >1200yds. Nosler just came out with LR AccuBonds the other calibers but apparently not enough call for us 3/8" bore fans.

Nolser lists the lower expansion limit of the AB LR at 1300fps as opposed to the 1800fps of the 375/260gr AB. The 7mm 168gr AB LR has a G1 BC=0.652 and G7 BC=0.352. the 308 AB LR has a G1 BC=0.73 and a G7 BC= 0.366.

This leads me to believe that for ELR (not LR<1000yds) the UltraMags in either 7mm or 30cal are a better choice. I am looking at the 7mm UltraMag as my next LR rig for this very reason.

But even my lowly 375 Ruger with a long barrel delivers 2000ftlbs at 630yds and 1800fps at 670yds. Anything up close and personal is going to see the destruction of 5200fllbs of Nosler's finest.

I ain't giving that up ever!!!

 

[Doublezranch]

The great news is that I have a 7 ultra, full custom 300 ultra, semi custom 338 ultra to go along with my 375 ultra respectively. All of them do a single job for me whether it's deer, bear, goat...etc. I hold my ultras very close to my heart as I've shot targets being animals, paper, or steel at or close to 1k. I hear what your saying when it comes to really big bore rifles. They were not ment for shooting long distance. However, if there's a way....I'm going to find it with my 375 rum!!

 

[Lefty7mmstw]

The great news is that I have a 7 ultra, full custom 300 ultra, semi custom 338 ultra to go along with my 375 ultra respectively. All of them do a single job for me whether it's deer, bear, goat...etc. I hold my ultras very close to my heart as I've shot targets being animals, paper, or steel at or close to 1k. I hear what your saying when it comes to really big bore rifles. They were not ment for shooting long distance. However, if there's a way....I'm going to find it with my 375 rum!!

Dang, that's a lot of rum. I have a 7rum(just picked her up- still no top end on her) and a 300rum. I'm still using the 338win and 375 h@h, but they do me well. I think the 250 grain hornady may have some merit for stretching your 375 rum's legs a bit.
Hornady Manufacturing Company :: Bullets :: Rifle :: Choose by Caliber :: .375 375 CAL :: 375 Cal .375 250 gr GMX®

It's only a .430 bc, but you ought to be able to launch well over 3000 fps with your rum.

 

[Moki]

I load with RL17 powder/260gr Accubonds for my 21" barreled 375RUM = 3020fps.

Super accurate combo.

 

[Doublezranch]

21 inch barrel? Goodness!!! Did you have to put 2 muzzle breaks on her to calm the mules kick?

Thanks Lefty, 250 is another great choice. I'm going to give the 260 accubonds and the 320 CEB's a whirl. It's going to be a "blast" for sure!!

 

[Doublezranch]

Anyone use Vit n560 in there 375?

 

[Moki]

21 inch barrel? Goodness!!! Did you have to put 2 muzzle breaks on her to calm the mules kick?

Thanks Lefty, 250 is another great choice. I'm going to give the 260 accubonds and the 320 CEB's a whirl. It's going to be a "blast" for sure!!

No brakes = I installed a magnum grind to fit Kick-eez recoil pad.

When the scope is off I install an XS Sights tall Weaver backup ghost ring sight my loads for this are 350gr TSX @ 2440fps.

 

[Doublezranch]

That's gorgeous. Looks like you have everything you need.

Awesome....

 

[Moki]

I spent 7 years working mostly solo as a self-employed free miner (prospector) in Central /Northern British Columbia, Canada.

I legally carried handguns most powerful was my Ruger 4.25" barreled SRH in 454 Casull loaded with 405gr WLNGC's @ 1330fps long guns I started by carrying Rem 870 12 gauge shotguns then a Marlin 1895GS 45-70 but all of these guns lacked distance when it came to hunting season.

So I put this 375RUM together to do double duty as a defence and long range hunting combo.

With the VX3 4.5-14X40mm B&C reticle scope mounted with a 200 yard zero the second B&C reticle line down is zeroed at 460 yards when I do my part I have repeatedly put 3 260gr Accubonds into 6" at that range.

I shot my 24 3/16" B&C interior grizzly @ 230 - 250 yards with a 300gr Partition @ 2800fps.

 

[Kennibear]

Moki

Nice critter!!!

If anyone has experience with VihtaVuori's N5XX series powders in this caliber I too would be interested. N540 orN550 is better suited to the 375 Ruger but N560 is their slowest for the big mags.

When the N5XX series first arrived in August of 1995 they were marketed as a "high energy" powder. I assume from the burn rates and charge densities that they use less powder and occupy less space. I have run out of room in the 375 Ruger using 300gr bullets over 80gr of 4350 but would like to stay with 4350 burn rates in this weight bullet. Hence the search for high density (re: high energy) powders.

If anyone has some load data please post to this thread.

Thanks!!!
Kennibear

 

[Moki]

RL17 has the same basic burn rate as IMR4350

When RL17 was first released I was told to use IMR4350 data

 

[Kennibear]

Thanks Moki!

Already trying RL19 w/300gr bullets.

Did some research on the Lapua website:
Products - Lapua

They don't list either the 375 RUM or the 375 Ruger but the 338LM and others do shed some light. The N5XX correspond to the same burning rate as the N1XX series, that is N560=N160 or N540=N140 in overall powder speed, fast/slow. The N5XX contain nitroglycerine (glycerol) to boost energy and seems to increase velocities over single based N1XX powders by about 100fps. You can interpolate a load from another caliber if you can find a similar weight of a known powder. For instance if you are using 96grs of 4350 and another cartridge/load of the same pressure level also uses 96grs of 4350 then the N1XX/N5XX load for the second cartridge would be close to what you could use, -10% to start and building up from there.

Lapua's website lists N570 which might be just the ticket in 375 RUM. I have never seen it on this side of the pond but I am keeping a sharp eye out for it now.

Hope you guys can use this info.