Barrel wear or a manufacturing problem?

[JAS-SH]

When you build a rifle and you know all the components that go into the build diagnosing problems becomes really easy.

Diagnosing problems is based on assumptions based on facts and experience. The big elephant in the room - the shooter, is looked at first. Powerful cartridges require more from the shooter. So, can the shooter handle the recoil? If the shooter is experienced with large cartridges then there might be a problem with the rifle. Simple process of elimination. And so on...

Then to the rifle. Assuming (but tested assumptions) that the rifle is put together correctly the next question is - was there a gunsmith involved, and if so, did that person have a good track record, and most importantly, experience with chambering the particular cartridge?

Diagnose from most likely to less likely. In my personal experience it tends to go that way. The latest problem I personally encountered was the result of a problem with the contact between the stock and the rear bag. Way down the list but it did not take very long to find.

All that said and done, the barrel is usually the culprit. And that includes the gunsmith if there was one involved.

 

[Aftermath]

That specific Berger calculator is flawed, it's only good to tell you if you don't have enough twist, it DOES NOT tell you that you have too much twist. Put in their 300 230gr, fps 5000, twist of 1, it says you are good to go.... blahhahahaha, BS.

Also not clear to me where the accuracy is failing, is it 100yds, or 1mi? I assumed this 300PRC build was for long distance.

More digging for punching one hole at long distance, is showing up that you choose a twist on the low end of rpm's that stabilize the bullet+muzzle fps, and when you get near max rpm's for bullet the accuracy starts to suffer. I myself cannot validate that, others can though.

Not flawed at all, maybe misunderstood.
Sure.
5000 fps is stable. Of course it is. That fucker is spinning.
Sure...round construction would dictate whether it would stay together but the SHAPE is good to go.
Notice that it IS stable as OP advertised velocity, etc. Try using other, slower twist rates, as you have stated.
Now...try decreasing velocity and see just how slow you can go with good stability.

 

[Genin]

Thermal shift from the carbon barrel? I know for my carbon barrels I will absolutely have a shift after 10 rounds if I do not allow them to cool (less in my PRC). Even though they look like those big fat truck axel steel barrels, they don’t necessarily behave like them in my experience. Once again, just something I’ve observed personally. Might consider that if you get another barrel. Get a good old steel pretty fluted one or something.

 

[Baron23]

You need glasses then. This is a machining anomaly. Nothing to do with normal fire cracking.

View attachment 8686432

Are you familiar with with machining?

I have zero idea why you are upset. I said nothing offensive to you at all.

As for that little spot in the groove, dunno what it is. Looks a lot like the reflection seen elsewhere it the pic. Ot it could be a very small flaw. I can’t really tell

Cheers and I hope your day gets better. Positive energy, yeah