7mm Rem Mag converted to 7PRC

Bfish22

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And I'm confident you'll, easily, be able to work up an accurate load in your confidently built semi custom Tikka 7PRC. :)

This size case are generally pretty forgiving and have a fairly wide sweet spot. I don't have a 7PRC but my 7 Blaser is kind of like a fraternal twin to the 7 PRC and it has probably been one of the easiest rifles I've ever owned to keep in tune.
I’ve been wanting to do a 7 blaser for years. I held off because of lack of brass options. Once lapua, Peterson or adg brass is available, I’ll start my prc.
 

Gila

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You assume a lot. I’ve read everything you’ve read. I’ll confidently build a 7 prc on my tikka action and confident I’ll be able to work up an accurate load with 180 vld’s.
Not assuming anything.....that’s the way it is take it or leave It.
 

Gila

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You dont get it!!! Literally everything you have said about the 7PRC has been wrong, do some research or quit spreading misinformation
And I'm confident you'll, easily, be able to work up an accurate load in your confidently built semi custom Tikka 7PRC. :)

This size case are generally pretty forgiving and have a fairly wide sweet spot. I don't have a 7PRC but my 7 Blaser is kind of like a fraternal twin to the 7 PRC and it has probably been one of the easiest rifles I've ever owned to keep in tune.
Sure you can, you will just have to single feed it. Won’t fit in the magazine.
 

Bfish22

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Sure you can, you will just have to single feed it. Won’t fit in the magazine.
It’ll fit fine.

7mm prc case- base to bottom of neck = 1.993”
Berger 180 vld oal = 1.506
Boattail of 180= .243
With boattail below case neck 1.993”+1.50”-.243= 3.256” coal.

That leaves .144” room in a tikka magazine.

With a .287 neck depth, the .144 should be plenty of length to seat out toward lands from there.
 
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Gila

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It’ll fit fine.

7mm prc case- base to bottom of neck = 1.993”
Berger 180 vld oal = 1.506
Boattail of 180= .243
With boattail below case neck 1.993”+1.50”-.243= 3.256” coal.

That leaves .144” room in a tikka magazine.

With a .287 neck depth, the .144 should be plenty of length to seat out toward lands from there.
good luck with that....You are going to need all of the luck you can get!
 

Rob5589

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Not necessarily. The Barnes LRX is a very long bullet like the ELDs. If you look at the link I provided, the 180 ELD is too long when tuned and won’t fit in the magazine. I know you guys don’t understand how to tune your loads, but the first thing you do with a bullet is hit jam then back off 20 thousands. Then do your ladder test and get your velocity where you want it. Then sink the bullets 3 thousands, fire a 3 rd group and keep sinking the bullet every 3 thousands until the groups tighten up. Once tuned, almost guaranteed that you will exceed SAMMI COAL of 3.34” with the 7 PRC. This is nothing new....same issue with other long action cartridges when shooting high BC bullets. There are various bottom metal makers that address this COAL issue as I have already stated, and it is not a cheap solution. Do a search here on a COAL that exceeds magazine length....see for yourself!
Monos jump. Barnes recommends starting at .050. .050 to .070 is pretty common. I've never measured my Tikkas, just use the Barnes rec and both shoot very well. I believe Hammers recommends about the same. Loading a vld is much different from a mono.
 

B23

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The case for my 7 Blaser is a little longer than the 7 PRC. I shoot 180 Berger Hunting VLD's, COAL to touch is 3.265. My load is 68.5gr RL26 and out of my Hart 8tw finished at 26 barrel they run 3088-3100 that's well off a max load. I don't believe I'm leaving much of anything on the table by stretching them out further.
 
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Well suppose I’ll add to this dumpster fire of a thread. I have a 8.5 twist barrel (#2 benchmark 23”) inbound for the sole purpose of building a 7prc tikka.
To the OP, slapping a 8 twist 7prc barrel is all you need to do, no mods needed and the ammo will fit and feed fine in your tikka mag. Lots of guys will be doing it and I suspect in a year or two there will be factory tikkas in 7prc available.
Loading 185-190gr bullets will start eating into your case capacity to fit, but 180 lead and 170 copper bullets should be fine. I plan to run 169gr hammer hunters if they shoot good. Hopefully I can get them 3000fps, but 2900 will kill things pretty dead too. Good luck with your project, maybe we can compare notes
 
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R

RSC12

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Well suppose I’ll add to this dumpster fire of a thread. I have a 8.5 twist barrel (#2 benchmark 23”) inbound for the sole purpose of building a 7prc tikka.
To the OP, slapping a 8 twist 7prc barrel is all you need to do, no mods needed and the ammo will fit and feed fine in your tikka mag. Lots of guys will be doing it and I suspect in a year or two there will be factory tikkas in 7prc available.
Loading 185-190gr bullets will start eating into your case capacity to fit, but 180 lead and 170 copper bullets should be fine. I plan to run 169gr hammer hunters if they shoot good. Hopefully I can get them 3000fps, but 2900 will kill things pretty dead too. Good luck with your project, maybe we can compare notes
Now that's exactly what I was hoping to hear. Thanks for bringing this thread back around. I definitely wasn't trying to open a can of worms like that.

Like I said I'm pretty new to this and was just trying to find out what would be needed and if it's worth it. Sounds like it's possible and could be a fun project.
 
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You bet. With the tikkas the only considerations are to have a mangum bolt face, which you have and the long bolt stop, which you also have. I’m converting mine from a 6.5prc, so I had to get a longer bolt stop. I made a kimber wsm into a 6.5prc which has a similar restrictive mag length issue (3” in that instance).
I plan to do the same process for reloading the 7prc; That being seat my bullets to max magazine length from the get-go and slowly add H1000 powder until I’m happy with the velocity and accuracy between a couple different bullets. Norma 165gr bond strikes and 169 hammer hunters would be top contenders for a do-all bullet to 600yds
 

EdP

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Back to the OP's question. I would sell the 7 Rem Mag and buy a 7 PRC. Do it while the 7 RM is still very popular.
 

philcox

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To OP. I am building a 7PRC out of a Tikka Magnum. Getting a CarbonSix 20" 1:8 twist prefit barrel. Throwing is in a XLR Chassi. The mag for the chassi is long. I PLAN on handloading the 168 LRX, BUT I have heard that the factory CX (I am in California) my shoot very well (1/2 moa is my goal). If it does, I may just stock up on it as the cost is about the same with current component prices. I should have all the pieces for the build in a couple weeks, and will let you know how it goes. I am essentially converting my Tikka Magnum action to a 7PRC.
 
OP
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RSC12

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To OP. I am building a 7PRC out of a Tikka Magnum. Getting a CarbonSix 20" 1:8 twist prefit barrel. Throwing is in a XLR Chassi. The mag for the chassi is long. I PLAN on handloading the 168 LRX, BUT I have heard that the factory CX (I am in California) my shoot very well (1/2 moa is my goal). If it does, I may just stock up on it as the cost is about the same with current component prices. I should have all the pieces for the build in a couple weeks, and will let you know how it goes. I am essentially converting my Tikka Magnum action to a 7PRC.
That would be awesome. I'm very intrigued with this build.
 

philcox

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To OP:

Finally got to Grouping today. I tested 2 loads that I had found "nodes" on in a ladder test:
- 168 LRX, 68.1g H1000 COAL 3.20
- 160 CX, 71.1g H1000 COAL 3.29

I shot 3 shot groups. Let barrel cool to touch in between each group. Same setup for rest etc. I shot in this order:
  1. 3 Factory 160 CX - Chrono with MagnetoSpeed to see what they were at, AND to heat up the barrel so my hand loads could be as "similar conditions" as possible - Note the Factory 160 CX: 2869, 2853, 2845 ... so essentially 2855 out of my rifle
  2. 3 Hand load 160 CX: Shot 1 & 2 were .099 MOA, 3rd shot turned it into a 1.265 MOA group
  3. 3 HL 168 LRX: 1.785 MOA
  4. 3 Factory CX: Shot 1 & 2 .290 MOA, 3rd took it to 1.091 MOA
  5. 3 HL CX: Shot 1 & 2 .216 MOA, 3rd took it to .622 MOA (I am noticing a trend here, not sure of ammo/rifle or shooter getting lazy on #3)
  6. 3 HL LRX: 1.722 MOA (confirms first group)
  7. 3 HL CX: At this point, I knew the CX was the load for this rifle until I can get some diff powder to try with the LRX, because I WANTED the LRX to win. Slapped the MS Chrono back on and: 3010, 2974, 3011 ... Avg ~3000
So at this point, since I want to bear hunt with it, I am going to stick with the 160CX. I will load up another 100 and do some more shooting and chrono to get better data, and to see if the 1,2, then 3 issue is a shooter or rifle issue.

Primary Load: 160 CX @ 71.1g H1000 and COAL 3.29, ~3000 fps out of a 20" Carbon Six barrel.

Now to Zero with that load, as you can see my impact and POA were consistently off.
 
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