7mm300RCM Opinions

Discussion in 'Long Range Hunting & Shooting' started by IHFarmer07, Oct 10, 2018.

  1. IHFarmer07

    IHFarmer07 Well-Known Member

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    Ok question for all of you, after A LOT of research for finding an AFFORDABLE short action cartridge that can still send bullets at a respectable to high velocity for the next build. Not sure if it would be able to fit in a short action or if it is a viable option, thus the reason I'm here asking. The 6.5 prc came out recently and while I kind of want one....it still don't seem to pop out like say the 7saum, 6.5saum or the Sherman Shorts as far as the velocities I would think it should be able to be at and compete with those other a little better. The affordability and plentifulness of the brass of the saum and Sherman are a turn off. If the 300 RCM can get to 2800-2950fps according to my Hornady edition 10 reloading book with 165-168gr bullets why can't the 6.5prc reach that and then some with 147's? Is it because the long 6.5 bullets extend into the case too much?
    What kind of ballistics would a 7mm bullet in the 300RCM generate? Would it not be a great all around short mag on a cheaper side of things? According to the Hodgdon reloading data the 6.5PRC only gets 3100fps+- some fps with 120gr bullets?? What am I missing here?
     
  2. highdrum

    highdrum Well-Known Member

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    If you look at the 6.5 prc saami print, it has a ton of freebore, too much to load to lands in a short action with any bullet. It should be run in a long action. Proper setup and I'm sure it'd push them @ 3000 or faster. A 7saum is a better mousetrap pushing 162-168gr pills, same bc, velocity and more energy.
     
  3. IHFarmer07

    IHFarmer07 Well-Known Member

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    I'm sorry I'm not sure where/what to look at on prints for freebore….kind of new to reloading always been a off the gun store shelf rifle/ammo person until recently.
     
  4. MudRunner2005

    MudRunner2005 Well-Known Member

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    Just build a 7mm SS (Sherman Shortmag). Better design, and Rich sells proper headstamped high-quality brass for it on his website.
     
  5. IHFarmer07

    IHFarmer07 Well-Known Member

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  6. WildRose

    WildRose Well-Known Member

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    Why limit yourself to a short action?
     
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  7. IHFarmer07

    IHFarmer07 Well-Known Member

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    Because the short actions are cheaper to get, factory Remington and aftermarket, lighter. I know I should know by now that any short action cartridge with “magnum velocities” don’t belong in a short action if your going to shoot hand loads eventually with bigger bullets and the people that make such rounds should accommodate for that but don’t.
    I really would like to have a 7ss or 6.5ss but dang the brass is expensive!!! Even the new prc is cheaper but Hornady brass from what I hear is just that, “cheap”, and SAUM brass is not much better priced with a rebated rim and hard to find. So that brings me to something that is saami approved, factory ammo is on the shelf if I need it and once you do go to a long action from what I’ve read you do get around the 3000fps with 147-150’s. So by that time with a long action I believe there are better contenders out there.
    It just amazed me at how fast the 300RCM with its 30 cal 178-180bullet at a COL of 2.830-2.840 can get possibly 2600-2650. I still think a 6.5prc necked to 7mm would work great but I have no idea, I’m still learning about the trade/profession/art. Still would probably need a long action though. I can see on a print of a reamer where and what the freebore is but on a print of the cartridge I don’t have the eye for that and like I’m saying I’m still learning the art. Can’t wait to start reloading when I catch up on bills and save money for reloading and another build, 3 rifle builds in a year got a little more expensive than I thought!!!
     
  8. Buttermilk

    Buttermilk Well-Known Member

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  9. IHFarmer07

    IHFarmer07 Well-Known Member

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    I have talked to 2 rifle builders GAP and PVA and both said that they have no problems with putting the 6.5 PRC in a short action, they had no idea why a person would put it in a long action unless your shooting F class to get every little bit of FPS a person can get out of it which they also said that if you go long action there are way better cartridges and that's why the 6.5 PRC has a purpose.
    I have looked into the 7saum case and the prc is shorter by .005 and people have no problems with those in the short action with 180's....heck I watched a guy on you tube shoot a 7saum very well out of a rem short action hitting mild jugs at a mile and 2000yrds. So in the end I think I have made my decision to move on with the 6.5 PRC, I really liked what I heard from 2 places very familiar with the round.
    I still think necking up a 6.5prc to .284 would be a cats meow for a short action 7 mag caliber!
    I also looked at the 300prc and I think this cartridge will be a great success both in 30 cal and would be and ultimate case to neck down to .284, in .284 that thing would be sweet!!!....time will tell what will be out next, these new aged cartridges are something to really look forward to, hopefully an awesome .284 will be in the works soon!
     
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  10. IHFarmer07

    IHFarmer07 Well-Known Member

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  11. MudRunner2005

    MudRunner2005 Well-Known Member

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    The 7mm SS will fit into a true short action with no issues. It's specifically designed to fit into a short action with long heavy high-BC bullets seated at optimal length to utilize as much case capacity as possible.
     
  12. Buttermilk

    Buttermilk Well-Known Member

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    In actuality, A 7 PRC on the short case would likely have 3-4 gr less capacity than the SAUM case. The 7 SAUM case is a ballistic twin of the 280AI. A 7 PRC would be virtually the same ballistically.
     
  13. IHFarmer07

    IHFarmer07 Well-Known Member

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    Ya I just can’t afford the best right now though, lol I’d love to go with an ss cartridge. There’s also a + to the prc too, it is that I can buy off the shelf ammo when I need it. I don’t have things set up yet for reloading, hopefully by the time I get such rifle done I will be able to reload soon with it. I very much appreciate you guys with the help but at the price of the ss is just out of my league.
     
  14. IHFarmer07

    IHFarmer07 Well-Known Member

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    Hmm interesting enough though..... I bet the brass will bring new wild cat cartridges to the board soon enough though.