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375 Mercenary , the beast unleashed !

Swamplord

Private
Full Member
Minuteman
Feb 27, 2011
49
120
USA
Next week the 375 Mercenary goes public, reamer prints will be released, reamers, brass and dies will be available to all ...

It's been a long year and a half with a lot of obstacles to overcome but we have a major update for the 375 Mercenary project .

To those who had questions about availability of dies, brass and reamers for the 375 Mercenary ....

I have fully authorized Jeff Roberson at RCC to make and ship brass and dies for the public regardless if you are in the USA, Canada, New Zealand, Australia or any other country on the planet where RCC can legally export brass and dies to .... brass , 2 pc and 3 pc die sets are available here ....
https://www.rccbrass.com/product/37...PbcTDy0YgZsD258SZ6fz3wSqDA3ewSRFt7iZJXPjFkzmY

Reamers will be available through David Kiff at Pacific Tool & Guage and he has my approval to make and ship them to any destination he is legally able to from the USA http://pacifictoolandgauge.com/

Those who want full complete rifle builds for ELR competition or long range hunting I have John Pierce at Pierce Engineering fully authorized to build rifles on his exceptional 10X action, he is currently building two long range hunting 375 Mercenary rifles for us on the 10X action and McMillan A5 Super Mag stock with the Cadex bottom metal and mags that allow 4.6" loaded ammo length, can easily run the 375 gr CEB MTH bullets in the magazines , John Pierce has my personal reamer on hand and once our barrels are chambered he can use it for customers builds ... https://pierceengineeringltd.com/

High BC ELR bullets for the 375 Mercenary are available from Jason Sejnoha at Badlands Precision and we are working out the details for a magazine friendly high bc, copper, hollow point, tipped hunting bullet tailor made for the 375 Mercenary that will also work in other cartridges ...


375 Mercenary testing and load data was established by me, using the proven Cutting Edge Bullets from 350 gr to 402 gr in MTH, MTAC and Lazer format, Daniel Smitchko at Cutting Edge Bullets supplied the bullets for the initial testing and load data accumulation

Our friends in Canada can have complete builds done by Dennis Lair at Go Ballistic Gunsmithing, he was involved with the 375 Mercenary project as our contact in Canada, has built a few 375 Merc rifles for local shooters http://www.goballisticgunsmithing.com/


as mentioned earlier, the 338 Mercenary, 408 Mercenary and 416 Mercenary reamers are available as well but at this time only the 375 Mercenary brass is being made, which can be simply necked up and used ready to load and shoot, they all share the same case design and headspace, if a gunsmith were to order all or several of the reamers he would only need one go guage for all of them, we will be doing the 408 Mercenary and 416 Mercenary headstamped brass at a later date

Cadex is the bottom metal and magazines we went with for the Pierce 10X 1.6" actions, the mags allow for ammo coal at 4.6" which makes the 375 Mercenary a repeater friendly cartridge

https://www.cadexdefence.com/produc...RtU6IGBblXQSrKE5bGAgjJbIk3XWssSm7zWVnspL8khWg

if any other questions, please post them here and I will answer when I can

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Wow $9.23 each for piece of brass. The bullet price is not bad for the 400 gr .375

Brass is cnc machined from super tough, hammer forged C260 brass rods, each finished case is identical in dims, weight and h20 capacity, no sorting ever needed ..... and cases are headstamped properly

Typical drawn/formed brass is annealed with every draw process in multiple stages to form the cartridge case, which softens the brass, work hardens during the draw then softens again, often times you get brass quality issues from different runs of brass that force you to sort brass and redo your load data work up

RCC brass is only annealed at the neck/shoulder after cases are completed, the case head remains super hard for long primer pocket life at peak pressures, no sorting is required and load data remains unchanged from brass made today and next year
 
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Cost money to run with the big boys.... But when you are trying to set records and shoot further then you can see it just might be worth it.... I have spent $77 per 20 for brass for my 30-378 before and I can tell you I swore about it...specially when 2-3 of them lost the primer pocket in 3 shots.... I say job well done for seeing this project done to the end... Dave
 
Cost money to run with the big boys.... But when you are trying to set records and shoot further then you can see it just might be worth it.... I have spent $77 per 20 for brass for my 30-378 before and I can tell you I swore about it...specially when 2-3 of them lost the primer pocket in 3 shots.... I say job well done for seeing this project done to the end... Dave
dave you are 100% correct some guys s are spending more on brass then 9.23 when you conside all the work that needs to be done on most brass in case prep and culling. that will never happen with rcc less then 1/10of a grain difference in a 100 lot batch . not to mention no case prep made perfect every time lot to lot case by case batch by batch year by year and this brass will have 5times the case life think about it brass that out lasts the next 2 or 3 barrels.
 
Oh i know your going to pay if you want to play. When the brass holds up to lets say 10 firings or more then its well worth the investment. Some of the 375 CT brass was done like you said after 3rd time it was fired and the 416 Barrett was not any better. As with all things in life quality cost more up front but you save on the back end.
 
Brass , Barrels and Bullets just have to be considered consumables... In The past I have been bad about crying over prices... Then go on a one day hunt and spend $150 on gas and lunch ... After I bitched about loaded ammo at $8 a shell...It really ends up being the cheap part of everything... Really if you are putting together a $12,000 or more rifle/scope package spending $1000 on brass isn't a whole lot out of line compared to what a guy gets tied up in reloading supplies for a regular hunting rifle if you figure $25-$3500 hunting set up and $300 for reloading supplies, Percent wise it comes out pretty close. The biggest cartridge I have is a 338 Edge... I have watched and read all I can about the super magnums.. I am unable to shoot prone so just can't make myself believe that it would be a good fit for me..But I still follow the threads on them and dream.... Dave
 
The old jamison 375ct brass only lasted 1-2 firings and we paid IIRC $2.50 a piece.

Such a frustrating experience that from then on I tried to base my builds off Lapua brass if at all possible. Got 38 or so cycles from my x47L brass so I feel better...

Eh, I suppose if you can afford a Mercenary build then you can afford the brass too.
 
RWS and Lapua brass for the 50BMG is over $5 a case.
I just necked a bunch of it down to 375/50 and ruined 10 pieces of brass in the multi step process.
If the RCC brass doesn't need culling the price while not attractive isn't completely out of the picture in my humble opinion.
 
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I'm on reload #7 on my Peterson 375 cheytac brass and there's still life left.

I am excited to learn more about this 375 mercenary and cnc turned brass!
 
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Hey guys! Are the reamer prints public?

Will be posting prints once we verify all dimensions are accurate in all the prints for the Mercenary family of cartridges in
338, 375, 408, 416, 423, 458 and 510 calibers, they all have same case dimensions and use one go guage

375 Mercenary brass is coming first and can be simply necked up to larger calibers and brass is ready to load n shoot
 
You got any pics of this next to other rounds in its class
 
Will this chambering fit the BMG bolt face. From what i gather it is the same rim and base dia as the 416 and 50bmg but with much stronger brass. What is the dimersions of that custom action you all are using on it. Length diameter bolt diameter. Seems really sweet. Can you post some pics of it as well. Thanks.
 
The 375 Mercenary is based off the 585 Nyati basic cylinder brass and doesn't need a 50 BMG sized action, all you need is a 375 CheyTac sized action like the Pierce 10x, Stiller Tac408 and similar, The 375 Mercenary has a slightly larger diameter body and is a bit longer than the 375 CheyTac for approx. 30 gr more in h20 case capacity, works on the same boltface, if you have a 375 CT chambered rifle all you'd do is run the 375 Merc reamer in and it will completely clean the old chamber out without having to set the barrel back, no boltface mods needed since rim diameter is the same
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Do you have any cross section pics too see what the web and walls look like
 
Testing was conducted in the dead of winter in -08 F temps to 75 F temps with a test rifle built on an Ashbury Precision (Stiller 1.4") action, 32.5" 1.7 tw 8R Rock Creek Barrel

Bullets shown are our own ELR design we call the Stealth Fighter LRC (Long Range Competition) 357 gr with a short bearing surface that incorporates our "stealth" design, (not available to public yet) they shot extremely well in my tests, a hollow pt hunting version counterpart is called the Stealth Bomber ..... more testing this summer, but so far they shoot awesome

the three cartridges in the lineup are ..
375 PRO (338 Norma Mag)
375 Mjolnir (500 Jeffery)
375 Mercenary (585 Nyati basic)
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When you cut a case. Cut a cheytac case and put beside it
 
Since these are milled. Why not put a ring around the flashhole inside the case to strengthen it.
 
Since these are milled. Why not put a ring around the flashhole inside the case to strengthen it.
the mercenary you see in the photo are not milled thy are swedged the ones being made are milled but putting a ring around the flash would weaken the case from what we have added n millage re moving material makes it weaker this brass is way thicker in the anvel and is made from stronger material
 
Anybody chamber one of these up yet? @badassgunworks do you have any range reports you could share?

I believe several were chambered but had brass issues so it kind of got side lined for a little while. Now I think you can get brass from RCC so I think we will see more on these.
 
I believe several were chambered but had brass issues so it kind of got side lined for a little while. Now I think you can get brass from RCC so I think we will see more on these.

Ya the rcc brass looks like awesome stuff and should really benefit the whole system. This cartridge looks like a good fit for something between the bmg stuff and the cheytac or XC.
 
Any updates on the 375 Mercenary? Is the RCC brass performing well?
 
Man I'd love to see those cross section brass cuts as well as a video of some of these complete builds!
 
Hello I’m getting ready to start my big build and I am very interested in the mercenary cartridge but I’d like to do the .408 mercenary. I’ve always been a little more parcel to the 408. How do I go about getting the reamer/dies for this and I saw you can neck up the .375 brass

Thanks
Tim
 
I've been waiting almost 2 years for 375 Mercenary Brass from RCC. Something to keep in mind.
 
I see it right now for sale from RCC. It’s a little pricey but what isn’t when it comes to big rifles
 
For sale doesn't mean available. Im excited to get the brass but never thought it would take this long. Price has gone up a bit since I ordered as well which is understandable. 2020 pricing was $9.40 each vs $11.18 now.
 
My .338LM Improved 40 brass took about a year. They go slow, but the results are impressive. The only minor headache besides the wait was that the primer pockets were too tight and needed to be reamed out before I could use the brass.
 
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Ah. I got ya my bad hope everything comes together for you. I just finished a 300 rum build for ELR so I’m just getting ready to start all over with this one
 
Have rcc make the brass in 408 dont neck up 375. To avoid donuts. After brass is made have reamer made to brass from ptg. Contact swamplord he can have it drawn up and submit to ptg i can build the dies . Your looking at $ 500.00 3 piece die set.if i am not mistaken swamplord already has the print for the 408 mercenary. What action are you planning on using
 
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I was planning on either the Pierce 10x or the 1.6” Stiller. Ok I will contact him to see about the print and thank you for the help and if all goes I’ll have you make the dies
 
I was planning on either the Pierce 10x or the 1.6” Stiller. Ok I will contact him to see about the print and thank you for the help and if all goes I’ll have you make the dies
Pierce 10x for sure the stiller does not like the higher pressures you run into bolt lift issues much quicker .
 
When they make the rcc brass do not let them add the ATB combustion chamber to the case head. It will cause issues. Have it made per original design
 
Are they still trying to make that ATB design work?
 
When they make the rcc brass do not let them add the ATB combustion chamber to the case head. It will cause issues. Have it made per original design
Is there a loading data for it? I have a 375 enabelr and I use 130gr of N570 but I'm not sure about this one. I'm in the process of building a Merc right now and it looks like it should hold about 4-5grs more powder than the cheytac?
 
Is there a loading data for it? I have a 375 enabelr and I use 130gr of N570 but I'm not sure about this one. I'm in the process of building a Merc right now and it looks like it should hold about 4-5grs more powder than the cheytac?
It depends on what bullet you're using of course.. if you're smart you would just build a 400 Warlord same case as the mercenary just longer
 
It depends on what bullet you're using of course.. if you're smart you would just build a 400 Warlord same case as the mercenary just longer
Well... I would love to but first of all, living in a place as liberal as Canada will impair your choice of toys heavily... I would have gone for 10x100 BWA if the 50cal gun was not banned. Anyway... I'm planning to use 400gr warner tool for the 375 Merc, I don't know if you tried it with N570 before but I want to collect any opinion possible. And to be honest, I'm new to ELR& ULR shooting, my 375 Enabelr is the first big boom stick I own. So could you kindly enlighten me that why 400 Warlord is better? Doesn't 408 cal bullets have less BC than the 375 ones? Correct me if I'm wrong but I remembered that's why they came out with 375 cheytac after the 408? Thanks!
 
For sale doesn't mean available. Im excited to get the brass but never thought it would take this long. Price has gone up a bit since I ordered as well which is understandable. 2020 pricing was $9.40 each vs $11.18 now.
Hi there, I also ordered from RCC but I just got an update in my mailbox stating that RCC declared bankrupt... SO I guess if you have paid for it you will not be getting both money and your brass now...