7 mag or is PRC actually better?

[TheCoyote]

It depends on the comparison you want to make. If you base it off of the way the prc and most 7RMs come in factory of the shelf form, then Id give the nod to the PRC. But if you are doing a build and put a fast twist barrel on the 7RM and build it for heavy for caliber bullets then Id give the edge to the 7RM

THIS! This is exactly what I have been wondering.
Factory rifles the PRC would be inherently better with the 1:8 twist.

However, if you were to have a custom barrel 7RM with a long throat and faster twist, would it out preform a 7 PRC? Would you have more powder capacity?

Some smart techy guy please chime in.

 

[MarkOrtiz]

Even at 2850 fps the 7prc pushing a 175-180 does everything I want. Pushing it faster with the 7rm only adds recoil.

 

[bmart2622]

THIS! This is exactly what I have been wondering.
Factory rifles the PRC would be inherently better with the 1:8 twist.

However, if you were to have a custom barrel 7RM with a long throat and faster twist, would it out preform a 7 PRC? Would you have more powder capacity?

Some smart techy guy please chime in.

Yes

 

[OverInfinite]

If I am not mistaken there are a couple rifles out there with fast twist 7RM. I think weatherby makes one and I thought savage sold a 1:9 at one time. I could be wrong. MOST people that are concerned with this PRC debate live 4,000+ ft of elevation, and I know my 24", 9.5 twist stabilizes the 180VLD at at 4,800ft.

 

[khuber84]

THIS! This is exactly what I have been wondering.
Factory rifles the PRC would be inherently better with the 1:8 twist.

However, if you were to have a custom barrel 7RM with a long throat and faster twist, would it out preform a 7 PRC? Would you have more powder capacity?

Some smart techy guy please chime in.

Just comparing as apples to apples as possible, the 7rm adg brass holds 82.5gr powder, 7prc adg is 80.5 gr. Prc has longer neck, so technically the 7rm does have a 2.2-2.5gr capacity advantage of boiler room below the neck. That's a 3% usable increase in capacity, that'll equate to maybe 1-1.5% increase in velocity at the same pressure, 50fps or so.

I dislike belted cases as the area just above the belt is generally not sized enough by the die, this causes extraction issues after 2-5 firings depending on pressure. Now you have to get a collet die that sizes the body, then FL size with shoulder numb. This has happened with my brothers 7rm adg brass, and a few other 300wm shooters I know.

I built a 7mm lrm, it's a longer bodied longer necked 7prc, was designed off the 375 ruger parent near 15 years ago. 375 ruger case was the parent that influenced the Ruger Compact Magnum, which spawned the 65prc, which lead to the 300 and 7mm versions(lil history for you). The 7lrm was designed by gunwerks, and adg has made their brass for a few years, prior was Hornady trash that really made it no better than a 7rm. My fired adg cases hold 87.3gr of water. It'll push a 180hyb at 3130 with N570 from a 22in barrel, near pressure here.

 

[TheCoyote]

Just comparing as apples to apples as possible, the 7rm adg brass holds 82.5gr powder, 7prc adg is 80.5 gr. Prc has longer neck, so technically the 7rm does have a 2.2-2.5gr capacity advantage of boiler room below the neck. That's a 3% usable increase in capacity, that'll equate to maybe 1-1.5% increase in velocity at the same pressure, 50fps or so.

I dislike belted cases as the area just above the belt is generally not sized enough by the die, this causes extraction issues after 2-5 firings depending on pressure. Now you have to get a collet die that sizes the body, then FL size with shoulder numb. This has happened with my brothers 7rm adg brass, and a few other 300wm shooters I know.

I built a 7mm lrm, it's a longer bodied longer necked 7prc, was designed off the 375 ruger parent near 15 years ago. 375 ruger case was the parent that influenced the Ruger Compact Magnum, which spawned the 65prc, which lead to the 300 and 7mm versions(lil history for you). The 7lrm was designed by gunwerks, and adg has made their brass for a few years, prior was Hornady trash that really made it no better than a 7rm. My fired adg cases hold 87.3gr of water. It'll push a 180hyb at 3130 with N570 from a 22in barrel, near pressure here.

That is great information thank you.
Is it difficult to find brass for you 7LRM? What about dies? Custom dies only?

 

[wind gypsy]

That is great information thank you.
Is it difficult to find brass for you 7LRM? What about dies? Custom dies only?

Brass and dies appear to be available on gunwerks website right now.

7LRM was THE gunwerks cartridge of choice before 28 nosler and PRCs were a thing.

 

[Doc Holliday]

THIS! This is exactly what I have been wondering.
Factory rifles the PRC would be inherently better with the 1:8 twist.

However, if you were to have a custom barrel 7RM with a long throat and faster twist, would it out preform a 7 PRC? Would you have more powder capacity?

Some smart techy guy please chime in.

Factory 7mm rem offering with a 1:8 twist:

https://www.gunbroker.com/item/1077776383

X-Bolt 2 Speed SPR - Bolt-Action Rifle - Browning

Experience Total Accuracy with the X-Bolt 2 Speed SPR. Features the new Vari-Tech composite stock with Browning OVIX Camo finish and is adjustable for length of pull, comb height and grip angle for a personalized fit to the rifle. Redesigned receiver and bolt. Fluted sporter-weight barrel is...

www.browning.com

 

[bmart2622]

If you want a fast twist, off the shelf 7RM, a Seekins would be pretty hard to beat

 

[Air Bear]

Yes

Not a math guy here. So 1:8 7rm would eek out the 1:8 7 prc on velocity. Does that mean it also beat it out on bc?

 

[Q_Sertorius]

Not a math guy here. So 1:8 7rm would eek out the 1:8 7 prc on velocity. Does that mean it also beat it out on bc?

BC is dependent on the bullets used.


____________________
“Keep on keepin’ on…”

 

[sdupontjr]

As mentioned many times, if you want to shoot longer heavier bullets, it would be cheaper to get a new barrel than buy a new rifle. In my case, I have n older Browning A-bolt II Medallion 7 mag. The older Browning allow for seating much longer rounds, thus allowing me to stoke up my rounds. The mag can be modified so that it allows longer seating.





That is the one issues that I noticed when dealing with my Tikka 7mag, that I eventually sold. You are limited to mag length. Now I bring this up because my buddy has a 7 saum, not PRC, but you'll get where I'm going. When I did load development for his SAUM with 4831sc, his 160 AB are seated so far into the brass, that he can't utilize to cartridge. His chamber is so short, that he can get about 2860 fps with the 160 AB. Hell my 20" CTR 308 get 2880 shooting 155 scenars with about damn near 20 less grains of powder. Now it drives tacks but he's limited due to his chamber. We tried RL26 but hit pressure way too early. To really open up his setup, he would have to have the chamber lengthened to maximize the cartridge.

So IMO, you can get 7mag ammo at just about any gas station from the Atlantic to the Pacific. If you want to say "look what I got" go get the newer PRC. But a seated out properly throated 7mag barrel will out run a PRC.

This is a great watch. He gets into what I'm talking about at the 19 min or so mark.

 

[bmart2622]

Not a math guy here. So 1:8 7rm would eek out the 1:8 7 prc on velocity. Does that mean it also beat it out on bc?

No, because they both shoot the same bullet

 

[Speaks]

I think the % of shooters that are going to see a benefit is very low. I have not clue if you are in that cohort or not. If you are buying a new gun anyway it would certainly be worth considering, if you are trying to tease out if its worth the investment to make a change my guess is not but hard to say.

If I were doing anything I might lean the direction of 6.5 PRC keeping the long range performance while stepping down in recoil, though I realize this was outside of what you asked.

If you are happy with your trusty RM I vote keep it, unless you wanted a new gun anyway and then PRC.

 

[Skibness92]

If it ain't broke, don't fix it! Keep the 7MMRM if it's working for you. But if you need to scratch the itch, buy the 7PRC as well!!