375 RUM guys

If you can supply COAL to the rifling (or the COAL you intend to use) with the 320 CE, in your rifle, and your barrel length, I should be able to provide some ballpark data to start with, using your chosen powder(s).
 
Thanks Racer.

Details are as follows....

375 RUM
26 inch tube
3.907 COAL

I am not fussy on powder. What ever seems to work the best or looks the best, I'm in. Thanks again!!

Jayson
 
We all got what we needed. However the 320 CE bullets are crazy expensive and just didn't give me what I wanted. I shoot the 350 SMK now and is truly incredible with hunting and accuracy.
 
When you guys are shooting the 375 RUM with after market barrels, and shooting 350 SMKs or the 320 CEs, are you using a standard SAAMI free bore reamer, or are you setting up the barrel with a longer freebore reamer than SAAMI?
thanks
 
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I used the standard SAAMI reamer. I felt that Remington gave plenty of freebore in their design. Since I built the 375 Zayne for my son off the 378 Weatherby, there's a huge difference in case capacity and freebore. What I have figured out is that freebore is certainly your friend when it comes to these 375's. When I first started out bullet offerings weren't what they are now so the easy choice was the SAMMI spec reamer. Now I would definitely play with the thought of designing a reamer with a little extra freebore for the super long high BC bullets.
 
I used the standard SAAMI reamer. I felt that Remington gave plenty of freebore in their design. Since I built the 375 Zayne for my son off the 378 Weatherby, there's a huge difference in case capacity and freebore. What I have figured out is that freebore is certainly your friend when it comes to these 375's. When I first started out bullet offerings weren't what they are now so the easy choice was the SAMMI spec reamer. Now I would definitely play with the thought of designing a reamer with a little extra freebore for the super long high BC bullets.
Ya, that's what I'm looking into... having a custom .375 RUM reamer made with a longer than SAAMI freebore.
What is the actual freebore for the SAAMI reamers?
My reluctance is having a reamer made that has a freebore that either too short or worse yet, too long.
I had some great input on the 338 Edge reamer I just ordered. But I already have a 338 Edge to tinker with freebore lengths... with the 375 RUM, I'm just starting to look into it. And I can't find anything an freebore length with the longer high BC bullets out there. Thanks
 
The reamer I used from elk ridge seats a 350smk with .300" of the drive band beyond the case mouth to be into lands. I didn't measure the reamer while I had it here but subtracting the interference and a bit of airspace in front of the case mouth, I'd wager there's a .250" freebore section on that reamer. Just fine for most hunting bullets.
I prefer my rifles with longer "throats" and with the 350smk, theres lots left on the table with that length so i cut the throat in mine .3755" dia, .490" depth, with a sharp leade angle. the smk has .550" bearing length, which slides the front of the band just into the top of the leade as the heel leaves the case. I seat them to 4.200", .200" neck contact, .150" slip to the leade contact. I had originally planned to step throat it like the +p/hybrid/bore rider throats that guys are doing, but decided not to with all the talk about erosion. 110gr retumbo/118gr r33 in formed Bertram brass checks 2875fps and no pressure. tight squeeze tho. With the standard rum throat 102 retumbo was showing me where the extractor was located, so I went ahead and rented the throater. working up 7828ssc now. hopefully get 2950. Every load I've tried groups under 1/2" unless I pull one. All my rifles have plenty of leg room and they all shoot better than I can.
 
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I was thinking of having a barrel maker/gunsmith barrel a .375 RUM action for me. I was then going to find a stock I liked and purchase a complete reloading set and learn to hand load for it. But after reading the last four pages, I realize I would have been way over my head.
 
I was thinking of having a barrel maker/gunsmith barrel a .375 RUM action for me. I was then going to find a stock I liked and purchase a complete reloading set and learn to hand load for it. But after reading the last four pages, I realize I would have been way over my head.
No you wouldn't. There's some technical looking stuff up there but it's just as straightforward as any other cartridge.. probably one of the easiest to build a load for I have ever been around
 
The reamer I used from elk ridge seats a 350smk with .300" of the drive band beyond the case mouth to be into lands. I didn't measure the reamer while I had it here but subtracting the interference and a bit of airspace in front of the case mouth, I'd wager there's a .250" freebore section on that reamer. Just fine for most hunting bullets.
I prefer my rifles with longer "throats" and with the 350smk, theres lots left on the table with that length so i cut the throat in mine .3755" dia, .490" depth, with a sharp leade angle. the smk has .550" bearing length, which slides the front of the band just into the top of the leade as the heel leaves the case. I seat them to 4.200", .200" neck contact, .150" slip to the leade contact. I had originally planned to step throat it like the +p/hybrid/bore rider throats that guys are doing, but decided not to with all the talk about erosion. 110gr retumbo/118gr r33 in formed Bertram brass checks 2875fps and no pressure. tight squeeze tho. With the standard rum throat 102 retumbo was showing me where the extractor was located, so I went ahead and rented the throater. working up 7828ssc now. hopefully get 2950. Every load I've tried groups under 1/2" unless I pull one. All my rifles have plenty of leg room and they all shoot better than I can.

what length barrel? Twist?
 
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