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.