375 ultra mag

Earnhardt

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Aug 25, 2012
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692
Location
NW Minn
I'm getting ready to shoot my 375 RUM for the first time this weekend...

I have 3 different seating dies, RCBS, Redding (standard), and a Forster Micrometer seating die
Anybody modify a Redding die for a micrometer seater?

Are any of you guys shooting the 353 Lehigh's?
If so, did you have a die company, or a machinist open up the top of the die to get the bullets to seat?

I have a .300" Freebore reamer
What is your freebore?
And at what bullet jump are you finding the best accuracy with the 350 Sierras?
BTO?
COAL?
(yes, I know I will tune my own loads/rounds, but I want a head start of sorts)

Thanks
 
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Chase723

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Joined
Nov 22, 2009
Messages
620
I'm getting ready to shoot my 375 RUM for the first time this weekend...

I have 3 different seating dies, RCBS, Redding (standard), and a Forster Micrometer seating die
Anybody modify a Redding die for a micrometer seater?

Are any of you guys shooting the 353 Lehigh's?
If so, did you have a die company, or a machinist open up the top of the die to get the bullets to seat?

I have a .300" Freebore reamer
What is your freebore?
And at what bullet jump are you finding the best accuracy with the 350 Sierras?
BTO?
COAL?
(yes, I know I will tune my own loads/rounds, but I want a head start of sorts)

Thanks

My .375 barrel came in this week and I just dropped it off at my gunsmith. I made him a dummy round to chamber off of. I’m shooting the 365gr Badlands SBII and also found that they were bottoming out on my seating stem (Hornady die w/ micrometer seating stem)…so I put it in a vice, selected a drill bit of the same diameter as the seating stem hole and just drilled the hole deeper. Worked great. The orifice of the original opening still rests on the ogive and centers it within the stem (beyond it and the tip doesn’t contact it at all) and so I’m pretty sure concentricity will still be as good as it can get with that setup. A VLD type stem might accommodate other monolithics but if you can’t get one this might work for you as well, only took a few seconds, and was free.
 

purpledragon

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Jul 7, 2009
Messages
188
Location
North Central Mississippi
Anything less than a 10-11 # rifle, even with a brake will still kick the **** out of you. I had one of the lightest 338 EDGEs built by Shawn years ago at 11# when he was building most of them at 15-16# to keep them at Idahos weight limit, and even with a brake and the 300g SMKs at 2850fps, it rocked your ***. Just food for thought. I wouldn't even think of a sub 10# rifle in a 375, that's just dumb...Then again, I like heavier rifles, they are easier to shoot at LR especially after you're huffing and puffing up and down the mountain...
I know this is way back in the thread,but, had to laugh at it. My 375 H&H Ruger #1 Tropical, I bought back in the 80's, I used to trick guys into shooting it, just to see their face right after squeezing the trigger, and that was with the H&H 270's no brake. I can just imagine with the bigger case....LOL
 

memtb

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Dec 30, 2013
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Location
Winchester, Wy.
I know this is way back in the thread,but, had to laugh at it. My 375 H&H Ruger #1 Tropical, I bought back in the 80's, I used to trick guys into shooting it, just to see their face right after squeezing the trigger, and that was with the H&H 270's no brake. I can just imagine with the bigger case....LOL

Recoil is a very personal thing! While admittedly I have little experience with the Ruger #1 in larger cartridges/calibers.....I have 2 cousins with the .375 H&H, and once had the opportunity to shoot a #1 in 416 Rigby! As never having shot a Rigby, I expected the recoil to be pretty impressive.....It was a let-down. The 416 Rigby in a #1 was a “kitty (silly political correctness) cat”! The shot was made standing, offhand......felt recoil was considerably less than my hunting rifle!

Summary: if someone has little to no experience with moderate to heavy recoil rifles/shotguns.....they are easily impressed! memtb
 

Earnhardt

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Joined
Aug 25, 2012
Messages
692
Location
NW Minn
My “amateur” boxing career helped prepare me for the 375 RUM…
But my melon is still feeling it 😊
 

Chase723

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Joined
Nov 22, 2009
Messages
620
@Earnhardt did you end up shooting the 353gr LeHighs? If so how’d it go? Barrel length/Powder/Charge Weight/Velocity? My barrel is hopefully getting chambered next week. Can’t wait to stretch it out. Seems like with lower weight projectiles people are using H4350, w/ the 350s H1000 (currently I’ve got neither of those)…w/ a 32” barrel shooting 365grers I’m contemplating using N565, N570, or even considering trying H50bmg…there’s no data out there for these heavy monos
 

Earnhardt

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LRH Team Member
Joined
Aug 25, 2012
Messages
692
Location
NW Minn
@Earnhardt did you end up shooting the 353gr LeHighs? If so how’d it go? Barrel length/Powder/Charge Weight/Velocity? My barrel is hopefully getting chambered next week. Can’t wait to stretch it out. Seems like with lower weight projectiles people are using H4350, w/ the 350s H1000 (currently I’ve got neither of those)…w/ a 32” barrel shooting 365grers I’m contemplating using N565, N570, or even considering trying H50bmg…there’s no data out there for these heavy monos
Is this Luke?
N570 will be too slow
I used RL26 with mixed results.
I’ll do more testing in the next month or so, but for now
I haven’t got the Lehigh’s or Sierra 350s to shoot very well
What is your barrel twist, and your free bore?
 
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