• Watch Out for Scammers!

    We've now added a color code for all accounts. Orange accounts are new members, Blue are full members, and Green are Supporters. If you get a message about a sale from an orange account, make sure you pay attention before sending any money!

Gunsmithing Magnum, or Ultra Magnum M700 Receiver for .300 PRC?

Wannashootit

Gunny Sergeant
Full Member
Minuteman
  • Sep 3, 2010
    2,122
    457
    FL
    .300 Win Mag = .513 base
    .300 RUM= .550 base
    .300 PRC= .532 base

    PRC is midway between the Win Mag and Ultra Mag. No tech information/prints available from Remington.
    Will the PRC feed through the rails (without modification) on the magnum action, or is the ultra-magnum receiver needed?
     
    Rim diameter is the same between all 3 so it shouldn’t matter what action is used. Unless there is an actual length difference between the respective actions it shouldn’t matter which one is used
     
    • Like
    Reactions: Taylorbok
    ^^^
    Thanks. Forgot that the RUM has a rebated rim. The wider feed rails on RUM action are because of the .550 body.
    But, question still remains whether the RUM action has a longer cutout? The PRC is close to RUM length, longer than "std" LA chamberings.
     
    Last edited:
    Do you have these rifles side by side to take actual measurements?
     
    option 3

    buy a custom action like an Origin

    putting money into an R700 is mostly a waste (see: sentimental or TacOps)
     
    ^^^
    Not mine- he already has a magnum action.
    I didn't ask for advice/M700 bashing that seems to be a pastime here- the new production receivers are in fact, pretty damned good from the few I've handled.
     
    • Like
    Reactions: fclassparadise
    if he already has the action then why are you asking? unless he has both?

    maybe next time word it better

    i'd still tell him to tell the r700 he has and get a custom that isnt an unknown
     
    Coal of the rum is 3.60. The prc coal is 3.70. I'm running a .300 prc on a r700 7rm long action. Depending on COAL, you might need to notch the feed ramp.
     
    I acquired a Rem 700 RUM action for cheap, I’m in the process of building a 300 PRC rig right now, my gunsmith told me the 300prc would work but needed to be run in a chassis or stock fitted with bottom metal with CIP length magazines
     

    Attachments

    • IMG_4953.jpeg
      IMG_4953.jpeg
      417 KB · Views: 53
    • IMG_1142.jpeg
      IMG_1142.jpeg
      545.3 KB · Views: 50
    • IMG_1140.jpeg
      IMG_1140.jpeg
      568 KB · Views: 49
    Last edited:
    Wow. That was very long. I think the commonly espoused answer is that by the time your r700 action is bought, blueprinted, threads trued, upgrades here and there and improved this or that, etc... to make a r700 as "square" and "precise" as a custom action such as an origin, that has some of the nifty doodads and features you are within dollars or cents of the origin, and you still have an action that can't accept prefits, doesn't have factory support for warranty issues, doesn't retain its value as well, and probably doesn't run as smooth. In other words it's seen as a waste of money. Nothing wrong with r700s, but I have run the numbers myself and walked away from getting an r700 worked over for that reason alone. If I am going to buy an action for 750 to 800 dollars I'm going to go a little further with my budget and get a custom action. Simple math and enjoyment of use is all it is.

    TLDR- b6graham is right.
     
    Last edited:
    So with very specific details on metallurgical differences, production methods, very specific clearances and tolerance stacking details tell us exactly why an Origin action is better. 'Because" is not a valid answer. Oh you mean you can not tell me or explain to me why it is better besides it cost more and is more elitist? So your opinion has absolutely nothing to back it up that is scientific, measurable or repeatable? So the Army and Navy Marine Corp. ordnance department are just idiots and got everything wrong just because? No I am not one that thinks that because the military uses something it means it is the best! I do mean that I can assure they have reasons other than "just because" behind their minimum mil-spec standards.

    I am not even a Remington guy sure I bought one for my son but I would never own one unless I was given one or got a fantastic deal on one I would never pay a premium for a R700. That is not because anything is wrong with them outside of mass production issues all brands suffer from. I just hated all the hype behind them. I natural hate anything that has too much hype behind it that is just me. That said I would run one any day of the week and not at all feel out gunned after it had been blue printed. I think Winchester, Howa, and CZ make a better action than Remington but again if I got a great deal on a Remington 700 I would not hesitate to compete with one or go into combat with one.

    Then again having worked in engineering for automotive industry and aviation industry I only care about actual design, materials, construction methods and results not hype and fan boy opinions.

    The gunsmith doing the work just has to have the entire action including the magazine and and bottom metal to make sure he can adjust the feed rails and mag box to fit COAL and geometry. Fat cases with little to no taper are harder to get to feed well. It is more important to talk to your gunsmith in advance. What ever action you decide to use you want the 'smith to be good at tuning it for the cartridge you want to use. They can also direct you to parts they think work best for what you want to do.

    I like to use Mauser actions for a lot of builds. Not a lot of modern precision 'smith work on Mauser's so you would not want to give your Mauser to a guy that does 99% Savage actions. Likewise I would not send a Savage to my Mauser guy. In the USA most precision gunsmith will be used to working on Remingtons and Savages.

    So talk with your 'smith first and talk to us chumps on this site latter! LOL

    My oldest son lives, eats and breaths military and has since he was a small child. My Dad and I both tried to talk him out of enlisting in the military. My Dad by the way is a 23 year old veteran and highly decorated. I had given him a NOS Unissued M48 Mauser for his 12th birthday. Maybe 2 years latter Cabelas had a crazy deal on Remington 700SPS on sale for I think $399. I called all around and only 1 store in my state had one left 24 hours after it had gone on sale. I drove there on roads that where nothing but ice. To get it for him. He is 24 years old and a veteran himself now and he still has that Remington. I got it for him in spite of my disdain for Remington 700 actions. I knew he would love it since US Army and Marine Corp. both used the Remington 700 action. I knew plenty of gunsmiths work on them and the aftermarket is crawling with support for them.

    As a teenager I would go by my dad's work and plenty of guys slightly older than I was where asking the First Sargent if they could take the M24 to the range. So just because I have disdain for the the hype associated with the Remington Model 700 does not mean there is anything wrong with the R700 besides my prejudice. All actions have some short comming. The Remington model 700 the bolt is a huge weak point.

    Zermat Arms does not do anything that makes me think they are better than a Remington 700, Winchester M70, Mauser or Savage. They want a premium for their action and the scope rail is not integral it is pinned. The both uses a floating bolt head like a Savage or Thompson Compass. It only has two lugs just like the Mauser and most bolt actions that came after it. The recoil lug is not even integral! The bottom is not flat it is round just like allt he cheap actions of today! The bolt body is not even forged! You do not get a trigger with it either. How is this action worth the money they want for it? What makes it better than a blueprinted Howa, Savage or Remington?

    They do not list anything in the marketing that tells me why I should choose this action outside of "just because"!
    Ughhh....I don't know where to begin....
    "I would never own one, but I bought my son one".....and you called an Origin "Elitest".
    Honestly I didn't read past this point.
    You snowed in or sumpin?
     
    • Like
    Reactions: msgriff and Jnull
    So with very specific details on metallurgical differences, production methods, very specific clearances and tolerance stacking details tell us exactly why an Origin action is better. 'Because" is not a valid answer. Oh you mean you can not tell me or explain to me why it is better besides it cost more and is more elitist? So your opinion has absolutely nothing to back it up that is scientific, measurable or repeatable? So the Army and Navy Marine Corp. ordnance department are just idiots and got everything wrong just because? No I am not one that thinks that because the military uses something it means it is the best! I do mean that I can assure they have reasons other than "just because" behind their minimum mil-spec standards.

    I am not even a Remington guy sure I bought one for my son but I would never own one unless I was given one or got a fantastic deal on one I would never pay a premium for a R700. That is not because anything is wrong with them outside of mass production issues all brands suffer from. I just hated all the hype behind them. I natural hate anything that has too much hype behind it that is just me. That said I would run one any day of the week and not at all feel out gunned after it had been blue printed. I think Winchester, Howa, and CZ make a better action than Remington but again if I got a great deal on a Remington 700 I would not hesitate to compete with one or go into combat with one.

    Then again having worked in engineering for automotive industry and aviation industry I only care about actual design, materials, construction methods and results not hype and fan boy opinions.

    The gunsmith doing the work just has to have the entire action including the magazine and and bottom metal to make sure he can adjust the feed rails and mag box to fit COAL and geometry. Fat cases with little to no taper are harder to get to feed well. It is more important to talk to your gunsmith in advance. What ever action you decide to use you want the 'smith to be good at tuning it for the cartridge you want to use. They can also direct you to parts they think work best for what you want to do.

    I like to use Mauser actions for a lot of builds. Not a lot of modern precision 'smith work on Mauser's so you would not want to give your Mauser to a guy that does 99% Savage actions. Likewise I would not send a Savage to my Mauser guy. In the USA most precision gunsmith will be used to working on Remingtons and Savages.

    So talk with your 'smith first and talk to us chumps on this site latter! LOL

    My oldest son lives, eats and breaths military and has since he was a small child. My Dad and I both tried to talk him out of enlisting in the military. My Dad by the way is a 23 year old veteran and highly decorated. I had given him a NOS Unissued M48 Mauser for his 12th birthday. Maybe 2 years latter Cabelas had a crazy deal on Remington 700SPS on sale for I think $399. I called all around and only 1 store in my state had one left 24 hours after it had gone on sale. I drove there on roads that where nothing but ice. To get it for him. He is 24 years old and a veteran himself now and he still has that Remington. I got it for him in spite of my disdain for Remington 700 actions. I knew he would love it since US Army and Marine Corp. both used the Remington 700 action. I knew plenty of gunsmiths work on them and the aftermarket is crawling with support for them.

    As a teenager I would go by my dad's work and plenty of guys slightly older than I was where asking the First Sargent if they could take the M24 to the range. So just because I have disdain for the the hype associated with the Remington Model 700 does not mean there is anything wrong with the R700 besides my prejudice. All actions have some short comming. The Remington model 700 the bolt is a huge weak point.

    Zermat Arms does not do anything that makes me think they are better than a Remington 700, Winchester M70, Mauser or Savage. They want a premium for their action and the scope rail is not integral it is pinned. The both uses a floating bolt head like a Savage or Thompson Compass. It only has two lugs just like the Mauser and most bolt actions that came after it. The recoil lug is not even integral! The bottom is not flat it is round just like allt he cheap actions of today! The bolt body is not even forged! You do not get a trigger with it either. How is this action worth the money they want for it? What makes it better than a blueprinted Howa, Savage or Remington?

    They do not list anything in the marketing that tells me why I should choose this action outside of "just because"!
    It that giant word soup, you say you hate things with hype, but hype the fuck out of savages? Did you forget your meds?
     
    • Like
    Reactions: msgriff
    Friend of mine has a couple 300 prc's and a 300 Norma built on remington 700 actions. They've all been worked over and fitted with the Wyatt bottom metal to run as long as they can. I forgot his max oal but I think he said 4" ? I know there was some work done to the recievers to allow his setup to work. A couple of them are in 338 edge.

    He got most of the actions he has from ptg in a fire sale as barreled actions. They were giving them away pretty much. Him and a buddy went in on a dozen of them for like $500 a piece.

    I've been going back an forth on the custom or worked over 700 thing myself here lately. I let my LTR sit stored improperly for about six years and the bore rusted. It's still a shooter out to 600, but then something crazy happens, so it's getting a rebarrel or its getting gone. I've got a takeoff 9 twist lilja that was pulled from my 300winmag with about 185 rounds down it and it has enough shank to save it.

    Debating on pawning the LTR off on some pour unsuspecting soul and going custom, or blueprinting the 700. I'll be doing the work myself, and I doubt I'll ever go the pre fit route anyway, so I really don't stand to lose much other than my time working the 700 over. Unless I wreck the action. Which is possible because I've never done this before. It'll be a learning experience whichever way it goes. 😂
     
    Friend of mine has a couple 300 prc's and a 300 Norma built on remington 700 actions. They've all been worked over and fitted with the Wyatt bottom metal to run as long as they can. I forgot his max oal but I think he said 4" ? I know there was some work done to the recievers to allow his setup to work. A couple of them are in 338 edge.

    He got most of the actions he has from ptg in a fire sale as barreled actions. They were giving them away pretty much. Him and a buddy went in on a dozen of them for like $500 a piece.

    I've been going back an forth on the custom or worked over 700 thing myself here lately. I let my LTR sit stored improperly for about six years and the bore rusted. It's still a shooter out to 600, but then something crazy happens, so it's getting a rebarrel or its getting gone. I've got a takeoff 9 twist lilja that was pulled from my 300winmag with about 185 rounds down it and it has enough shank to save it.

    Debating on pawning the LTR off on some pour unsuspecting soul and going custom, or blueprinting the 700. I'll be doing the work myself, and I doubt I'll ever go the pre fit route anyway, so I really don't stand to lose much other than my time working the 700 over. Unless I wreck the action. Which is possible because I've never done this before. It'll be a learning experience whichever way it goes. 😂
    If you’re going to try your hand at blueprinting it yourself and you already accept that you may destroy it, then you have nothing to lose

    Unless you have a 700 already and/or got it for dirt-ass cheap it makes more sense to start with an aftermarket action. There are dozens of actions to start from and the combo options are endless, especially if you’re going to start with something that’s a 700 clone. The newest hotness is the Coup De Gras from ARC but there are plenty of others
     
    • Like
    Reactions: XP1K
    If you’re going to try your hand at blueprinting it yourself and you already accept that you may destroy it, then you have nothing to lose

    Unless you have a 700 already and/or got it for dirt-ass cheap it makes more sense to start with an aftermarket action. There are dozens of actions to start from and the combo options are endless, especially if you’re going to start with something that’s a 700 clone. The newest hotness is the Coup De Gras from ARC but there are plenty of others
    I almost pulled the trigger on a coup. This is going to be a budget minded build though for now. New kid due on the 31st next month so money is tight. I've pretty much got all the parts to put the rifle together aside from some tooling. I have to make a fixture to hold the reciever so I can true the threads and I have to get a 308 reamer.

    If I was starting fresh, knowing what I know now I'd just go custom. And really that all comes down to return on investment. You won't get your money back on a remington reciever no matter what you do to it. A custom will always resale better.
     
    Congrats on the new kid. Is this your first?

    I know you said you’d probably never put a prefit barrel on it but it definitely is a viable option. Someone here did a remage conversion without any machining but it shot just as well as any other barrel option
     
    Congrats on the new kid. Is this your first?

    I know you said you’d probably never put a prefit barrel on it but it definitely is a viable option. Someone here did a remage conversion without any machining but it shot just as well as any other barrel option
    Second kid. A little better than four years apart.

    After I get my action trued I should be able to make my own pre fits.

    I thought about the remage route, and it does work, but, I just can't get past that savage barrel nut lol.
     
    Second kid. A little better than four years apart.

    After I get my action trued I should be able to make my own pre fits.

    I thought about the remage route, and it does work, but, I just can't get past that savage barrel nut lol.
    Nice. I have 3 boys, all 3 within 4.5 yrs

    Some of the barrel nuts are ugly as sin. I just don’t really care that much, as long as it shoots
     
    • Like
    Reactions: XP1K