# Firearms and Shooting > Projects and Home Builds >  7x47 Jumbo

## dashcats

Hi guys
I'm new to all this and don't have any reloading experience but would love to build a custom rifle in a custom wildcat. I'm an engineer so recreating the wheel using a different method works for me. I've been doing a lot of reading over the last year or three. I like what the ammunition companies have attempted to do with the short magnums but they all seem to have just missed the mark. If you load the long heavy bullets required for long range work into these cartridges they don't fit the short actions they were intended to be used in. 1000m is the new 300m. If you shoot under 300m then please ignore me. I read an article on the 7mm Fatso and thought it was a great idea with a well thought out set of goals. On the same theme, why not shorten the 338LM down to 47mm and necked to 7mm Cal. Nice long neck 8.7mm and a 40deg shoulder. You could seat a 180VLD with a COAL of 71.2mm and have a slightly higher case capacity than the 284Win. Make a great long range mountain rifle and I'm sure the F-class guys would give it a go. A true short action magnum.

Your thoughts?

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## Kiwi Greg

Forming the brass would be "fun"  :Have A Nice Day:

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## dashcats

Thats what I was thinking.

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## crnkin

Neck that fucker down to .1 cal and machine up some hollow point tungsten bullets, then ill be impressed!

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## robhughes-games

i say go for it. im interested. im just shooting my 7wsm in a long action to get over the short action problems. even just for the fun of doing it as a project and having something unique it would be fun. im assuming you have access to a lathe and mill? i would practice first and rebarrel something that you already have. maybe take a factor rifle you have and just set the barrel back a bit to get used to the gunsmithing thing. there are a feww little 'learnings' that im in the process of working out

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## robhughes-games

just post pics when you do do it!

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## dashcats

my current drawing

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## muzr257

So what action would you base it on?
Just thinking about the whole Rem700 v 338 LApua base size argument with bolt face issue etc?

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## dashcats

I don't believe there is anything commercially available at the moment.
I was thinking a short version of the Barnard PLM would be a good start.

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## Normie

Any WSM action would do it, wouldn't it? Or does the Lapua have a bigger case head?

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## stug

The Lapua case head is bigger than a WSM. Some smiths will build a Lapua on a Rem 700, others won't. The larger the case head the greater the bolt thrust for the same pressure.

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## Normie

I see the issue with available actions then.

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## tui_man2

Get a rem short action. Am long action over size bolt am shorten it to suit job done if you going to that trouble doing it youself in whole hog. Making an forming the brass wouldn't be to bad either.

Would feed like a worn out old whore tho but with work might not be to bad, an 2shot mag.

Go on you know you want to

sent from my Samsung s3 using tapatalk 2

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## tui_man2

I have thought of this what you are doing also, the norma necked down just goes easier, that's in long action tho. A grunty short action be cool tho. 

Following with interest :Grin: 

sent from my Samsung s3 using tapatalk 2

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## muzr257

Build it on a ruger No1 and no problems with mags or bolt face issues yes?

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## robhughes-games

thats only .07mm bigger than a wsm bolt face. you could do it on a savage action. or start with a 300rum case and blow that out. that way you can start with a standard bolt face. for example 338 Edge

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## 7mmsaum

> thats only .07mm bigger than a wsm bolt face. you could do it on a savage action. or start with a 300rum case and blow that out. that way you can start with a standard bolt face. for example 338 Edge


Are those Edges any good Robhughes ?

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## dashcats

Just had a look at the 300RUM case. If I keep the same neck length and 40deg shoulder and increase the case length from the first proposal (47mm) to 49mm I get the same case capacity as a 284Win. the 180vld's would need 2.9" COAL but could use 162 amax's under 2.8". Basically thats how the 7mmSAUM should have been done IMO. If we are looking for a little more horsepower than the 284 in a true s/a then need to use a fatter case me thinks.

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## robhughes-games

> Are those Edges any good Robhughes ?


7mm- i personally dont have one but i was developed by Shawn Carlock,( big into longrange, wrote in the nz hunter reciently, from the US). he has shot quite a few animals out past 1200m with his. think they are sending  300gr pill around 2950ish of the top of my head. ment to be quite an accurate round

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## muzr257

Tussock your phone is just bringing you down to the level of our lastest high school graduates - your jus two edumacated 4 sosiety 2day :Pissed Off:

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## leathel

a lot of stuffing around for not much gain.... open up a short action rem 700 in the mag box (Mill it back to the trigger and enlarge the box etc) and run a 7mmwsm ...or imrove a the saum a tad....or run a std 7mmSAUM with RL17 in a 24" barrel and get 3100fps with the 162 and its a 1K rifle.

 The SAUM std feeds nice and will do what a 280AI will do and just short of the Rem Mag and WSM...

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## crnkin

Tussock is starting to sound like tui_man haha.

I personally think the SAUM would do the trick, but, 300 RUM shortened would be cool, but using the lapua brass would be badass.

Theres actually a fuck load of nice options in 7mm these days right off the shelf. 

Chris

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## leathel

> Tussock is starting to sound like tui_man haha.
> 
> I personally think the SAUM would do the trick, but, 300 RUM shortened would be cool, but using the lapua brass would be badass.
> 
> Theres actually a fuck load of nice options in 7mm these days right off the shelf. 
> 
> Chris


SAUM is a shortened Rum case...you could blow it out a bit as its is tapered but it feeds well being tapered

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## Bill999

am I the only one who sees the problem going to all this effort for just better than 284 performance?
expensive brass that you then have to spend time forming and prepping to then have feed issues with
all to push a 180vld at what speed?
seems like a lot of effort and continual expense for a mediocre outcome. 

hallmarks of wildcat success are easily made cheeply sourced and created, and low effort to create action and brass wise
Man Im negative in the morning, fuck. I think im turning into my dad.......

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## dashcats

OK all you petrol heads, how about this for going mad.  Start with a 50BMG case and a little machining ending up with 47mm case with 30deg shoulder and the same case capacity as 7RUM.
Shown with 180 VLD at 2.8"COAL.

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## leathel

but what action will you put that in....will need to design a new one of those too  :Wink:

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## Bryan

Fat little bugger of a case. 

I think you should call it the 7mm Choad.  :Psmiley:

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## Spudattack

What about starting with a .375 Ruger? Has same case head as the belted magnums but no belt so you get extra capacity. Shorten and neck it down to 7mm, will fit in a standard action no problem.

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## Wildman

Some one has far too much time on their hands...

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## crnkin

haha

Lets all make a shorter case so we can use a short action, then make the case head 20mm so that we need a barnard gp 

hahahahahahahaha

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## robhughes-games

thats only .07mm bigger than a wsm bolt face. you could do it on a savage action. or start with a 300rum case and blow that out. that way you can start with a standard bolt face. for example 338 Edge

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## 7mmsaum

> thats only .07mm bigger than a wsm bolt face. you could do it on a savage action. or start with a 300rum case and blow that out. that way you can start with a standard bolt face. for example 338 Edge


Are those Edges any good Robhughes ?

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## dashcats

Just had a look at the 300RUM case. If I keep the same neck length and 40deg shoulder and increase the case length from the first proposal (47mm) to 49mm I get the same case capacity as a 284Win. the 180vld's would need 2.9" COAL but could use 162 amax's under 2.8". Basically thats how the 7mmSAUM should have been done IMO. If we are looking for a little more horsepower than the 284 in a true s/a then need to use a fatter case me thinks.

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## robhughes-games

> Are those Edges any good Robhughes ?


7mm- i personally dont have one but i was developed by Shawn Carlock,( big into longrange, wrote in the nz hunter reciently, from the US). he has shot quite a few animals out past 1200m with his. think they are sending  300gr pill around 2950ish of the top of my head. ment to be quite an accurate round

----------


## muzr257

Tussock your phone is just bringing you down to the level of our lastest high school graduates - your jus two edumacated 4 sosiety 2day :Pissed Off:

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## leathel

a lot of stuffing around for not much gain.... open up a short action rem 700 in the mag box (Mill it back to the trigger and enlarge the box etc) and run a 7mmwsm ...or imrove a the saum a tad....or run a std 7mmSAUM with RL17 in a 24" barrel and get 3100fps with the 162 and its a 1K rifle.

 The SAUM std feeds nice and will do what a 280AI will do and just short of the Rem Mag and WSM...

----------


## crnkin

Tussock is starting to sound like tui_man haha.

I personally think the SAUM would do the trick, but, 300 RUM shortened would be cool, but using the lapua brass would be badass.

Theres actually a fuck load of nice options in 7mm these days right off the shelf. 

Chris

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## leathel

> Tussock is starting to sound like tui_man haha.
> 
> I personally think the SAUM would do the trick, but, 300 RUM shortened would be cool, but using the lapua brass would be badass.
> 
> Theres actually a fuck load of nice options in 7mm these days right off the shelf. 
> 
> Chris


SAUM is a shortened Rum case...you could blow it out a bit as its is tapered but it feeds well being tapered

----------


## Bill999

am I the only one who sees the problem going to all this effort for just better than 284 performance?
expensive brass that you then have to spend time forming and prepping to then have feed issues with
all to push a 180vld at what speed?
seems like a lot of effort and continual expense for a mediocre outcome. 

hallmarks of wildcat success are easily made cheeply sourced and created, and low effort to create action and brass wise
Man Im negative in the morning, fuck. I think im turning into my dad.......

----------


## dashcats

OK all you petrol heads, how about this for going mad.  Start with a 50BMG case and a little machining ending up with 47mm case with 30deg shoulder and the same case capacity as 7RUM.
Shown with 180 VLD at 2.8"COAL.

----------


## leathel

but what action will you put that in....will need to design a new one of those too  :Wink:

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## Bryan

Fat little bugger of a case. 

I think you should call it the 7mm Choad.  :Psmiley:

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## Spudattack

What about starting with a .375 Ruger? Has same case head as the belted magnums but no belt so you get extra capacity. Shorten and neck it down to 7mm, will fit in a standard action no problem.

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## Wildman

Some one has far too much time on their hands...

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## crnkin

haha

Lets all make a shorter case so we can use a short action, then make the case head 20mm so that we need a barnard gp 

hahahahahahahaha

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