7mm PRC

[Wild Monkey]

Well I don't have a formula, but if you keep the same neck length then you altered the angle of the shoulder (if you keep the Shoulder location the same). Hey, do what you want, I know what works. You'll find out the hard way./// If you're talking about some fictional Cartridge you made up dave, you are the only one who knows the measurements. As was stated earlier, his post sounded like he kept everything the same, and that's not how it works necking down Brass. Something has to change, everything does not stay the same when necking down. Jud96 said: If you necked the .300 PRC straight down to 7mm, without changing the shoulder or neck length" this is an impossible statement.

 

[Wild Monkey]

I guess to summarize, Your "guesstimate" would be off by 0.021" so if you add that to your length theorizing it still comes in under 3.7", even if simply necked down. I still think a shoulder bump would be better setting the water capacity at ~85gr H2O. The 7mm-300 PRC could still be and easy formed wildcat. It's all just speculation at this point anyway.

If you bring the Width of the Shoulder in like the 7LRM, perhaps then you might have enough brass flow to make a "Simple Neck Down Fire-Form" Cartridge. Oh wait, not very simple really. Like all those fella's who jumped on the 7mm-300WM and soon found out the Necks were way too short. Earlier you showed an example of a Wildcat where you moved the Shoulder down while only slightly diminishing capacity, essentially shortening the Case. Doing so creates a large Donut that only requires Milling out. Nothing close to a simple neck down though. Any of the Kamikazi versions require the Neck to be Milled due to excessive thickness. I'm not totally star struck to ignore the negative there. For accuracy you keep a significant portion of the Frustum above the base of the Neck. This significantly adds to the OAL of a Cartridge which is near 1.6" when considering the 195 grain projectile. A simple necked down 300 PRC would deliver an approximate Base location according to your math of 2.32" + 1.6 = 3.92".

 

[Sniper97]

How would this compare to a 28 nosler? Assuming a longer freeborn with the 28 also. First glance I would say less powder for similar speeds? What are the chances of this hitting the market? How about barrel life? Thanks!

 

[Jud96]

How would this compare to a 28 nosler? Assuming a longer freeborn with the 28 also. First glance I would say less powder for similar speeds? What are the chances of this hitting the market? How about barrel life? Thanks!

In my opinion, I think it would fall between the 7mmRM and 28 Nosler.

 

[jpndave]

That's a pretty close description. The 28 Nosler is a bit more overbore.

In my opinion, I think it would fall between the 7mmRM and 28 Nosler.

 

[WahooYahoo]

https://m.facebook.com/story.php?story_fbid=2293458990932473&id=2028645630747145

Ive been following this for a bit. lower pressures, less powder, same performance or better than 28 Noz

 

[Jaredfeaster]

.

 

[Stan Clare]

Made ya look!

Has anyone made a reamer for this yet? Hornady hasn't published anything yet so I was wondering how many people have succumbed to their wildcatting will and ordered one up...

Been looking at 7mm for a while. Very interested in this one! Signed up and will be following with interest. Thanks!

 

[Wild Monkey]

I'd like to see something like this as a 7mm PRC:

View attachment 145506

Yes, I know it's close to the 7LRM, and even the Blaser, Similar capacity to the 7 Practical, and ...

~85gr H2O and PRC design philosophy. And if big bad Hornady comes out with it, should go and hopefully get mainstream support. One can hope. 180-195 launched comfortably 3000+ fps is what I'd like to see without going crazy overbore.

The only obvious flaw with this excellent diagram is it won't clean a 7mm Rem Mag Chamber.

 

[Rhovee]

I have a 300 PRC necked down to 7mm. It's slightly more efficient then a 28 Nosler. Barrel wear is slightly less. It's nothing magical. 24" barrel shoots 184's at 3100 with Retumbo(78g). 3070 with H1000 (77g) and 3120 with N570 (81g). Its accurate but so is the 28 Nosler. Throat has moved .013 in 180 rounds. I have shot three and let it cool. I like it, burning about 5 grains less powder than 28 Nosler. And it has about 7 grains less case capacity. Alex Wheeler built this for me.

 

[SammySTW]

I'm interested in this. My gunsmith has a 7-300 PRC reamer that he hasn't used yet, and I have a Bartlein 1:8tw carbon blank that I don't really have a plan for. I already have two 7 stws so I really dont need another big 7, but this 7-300 PRC sounds like it could be fun.
Rhovee, what kind of dies do you have for it?

 

[dave_halsey]

I opened this ****ed! haha I just had a 28 nosler built and I said it right at the start of the project that Hornady would come out with the 28prc the second my new rifle was finished. Made me look indeed.

 

[Rhovee]

Redding 300 PRC dies with .313 bushing. Necking down was a bit of a chore. Need to anneal after. Bushing die does not size the entire neck. Had to take it down with a cheap 7 saum neck die.

 

[SammySTW]

Redding 300 PRC dies with .313 bushing. Necking down was a bit of a chore. Need to anneal after. Bushing die does not size the entire neck. Had to take it down with a cheap 7 saum neck die.

Hmm, I already spend more time working on loading than actually shooting, so I dont want too many extra steps