7MM RUM??

Unfortunately, when I had mine the slowest powder we had access to was 7828 and I took that last barrel off well before powders like Retumbo, H50BMG or N570 were available.
I would guess using powders this slow would gain between 50-150fps, but this is a WAS at this point. Mine had a 8" twist even back then, but the factory barrel was 9 1/4" twist which lasted 600 rounds.
I got high velocities with 175g bullets, 100fps faster, with RL25 when it came out. No other powder then could match it in several magnums.

Someone must be shooting one with 195's and slow powders here.

Cheers.
I'm shooting a 7 RUM with a 29" barrel, 195 bergers with 90grns of 50BMG. Getting 3010 fps
 
Anyways I asked a similar question a few years back and it generated some good discussion. Here's the link

Thank you.
 
I have everything for a build except an action and a trigger. I will be using a brake and a Wyatt's box. I have a later version HS Precision Remington Sendero stock. It is a light stock. I imagine total weight will be 10-11 LBS.

Thanks to who responded with realistic numbers. The loading manuals were anemic. Barley above 7 REM Mag numbers.
 
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While I have and love a good RUM (7, 300, 338, 375), the Norma Mag case lets you run a shorter COL. Not a problem if you already have a Wyatt's box like I do for the 7 RUM, just something to think about if building new. The 7-300NMI is a rocket launcher,
What's the performance you are getting with your 7-300NMI?
THE 28 noz if Ryan pierce builds it gets 3150 with 195's. Can you go north of 3250?
 
Morning, mine likes the Rl 25. I'm also using Nosler Accubonds 160gr. Do not use the Nosler ABLR. They won't give you a consistent group unfortunately. It also likes super clean barrels. About every 8-9 rounds,
I concur with the RL-25 for the 7 and 300 RUM. I have enough to keep my pet loads fed for life but and no longer building loads with the Reloader powders. It's really to bad.
 
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