convert 7mm rum to 7mm STW ?

[valleysnyper]

Hi guys, I recently bought a Rem 70 in 7mm RUM thinking about re barreling to 7mm STW, my thinking was that the 7mm Rum would have a larger action than a7mm rem helping me to shoot heavier bullets with a longer overall length. Am I right in this thinking ? or am I barking up the wrong tree ? Lots of info that is getting confusing to me being fairly new to this
Anyone have any insight they can share ?

 

[MudRunner2005]

One of my 7mm STW's is built off a 700 CDL 7RUM action. Works just fine.

The action is the exact same size, the difference is the feed rails machined into the bottom of the action are slightly wider for the wide non-belted RUM cases to feed through, so it uses a slightly wider mag box and follower as well. That's the only differences in a RUM and a magnum 700 action. Everything else is the same.

You can literally take a 700 RUM action, and swap just the barrel to a 7STW and it will work fine. I had mine fully blueprinted and worked while he had it disassembled. That part's up to you and your budget.

 

[valleysnyper]

that's what I have, do you know what is longest COAL you can use in that rifle as a repeater ? magazine is longer than a standard 7mm rem isn't it ? what bullet/grain do you shoot and what twist barrel

 

[MudRunner2005]

that's what I have, do you know what is longest COAL you can use in that rifle as a repeater ? magazine is longer than a standard 7mm rem isn't it ? what bullet/grain do you shoot and what twist barrel

Same length. All Remington 700 long action mag boxes are built to the same OAL...Roughly 3.650". Some lengths can vary based on machining, just like anything else man-made some things may vary.

If you want a longer mag box and want to build the rifle correct, I would use a Wyatt's Outdoors 4.000" extended mag box. This will have to be installed by a professional gunsmith, as it involves milling out the bottom of the action, and the stock/mag well.

I have 26" barrels with 9.25" twists... Back then nobody offered any bullets much heavier than a 180 for a 7mm caliber. So, a 1:9 was standard. Nowdays they have the 195's and some other random wildcat bullets up to, and over 200 grains. So, I would go with a 1:8 twist to be on the safe side.

I shoot Berger 180 Hybrids in both of mine. One of mine is a factory original 2002 Sendero SF in 7mm STW that I special-ordered new when I worked at the gun store back in the day...It will always be left in original condition, because of the sentimental and rarity of it.

The other is a custom build that was commissioned around 2013-2014 by a buddy of mine, who not long after it was completed, ran into money problems. So I bought it from him because it was built by the same gunsmith that builds my rifles. He put a Sendero 26" heavy 1:9.25" twist factory take-off barrel on it. Thinking about rebarreling to a 1:8 twist and chambering it in .28 Nosler just to diversify my 7mm collection a bit more, since I already have one 7mm STW.

 

[valleysnyper]

alright thanks for all the help the past couple of days

 

[WildRose]

alright thanks for all the help the past couple of days

Good advice above. If I were building a new STW I'd go with a minimum 9 twist and maybe even 8.5 twist chambered specifically for the 170gr and heavier bullets.

 

[David Emerson]

For the stw you want a standard magnum box. The ultra box is widened and in my experience will not feed a standard magnum case well. If you need longer than 3.650 length buy the standard magnum wyatt,s box. They measure 3.83 long inside. If the bolt rides over the case take a wide jaw vise grip and bend the feed lips in a bit until the feed is good. Also the tit in front of the trigger will need to be milled off and the bolt stop set back. When I do them I also mill the rear bridge back .100 but that is up to the customer. More room for an unfired shell to get out.