Pressure?

[Barehandlineman11]

In my experience christensen pressure early. Your primers show beginning of pressure. I wouldn't pay too much attention on the brass markings. Christensen double ejector is stiff and ive seen marks on very low charges especially in softer brass. Buddy has 30 nowler and 7 mag in same gun. Both are border line unsafe with factory nosler ammo. Id back off 2 grains and work up from where you are

 

[FEENIX]

Do you have a chronograph? Two of your H1000/160 gr bullet reloads are over book max for powder charge; one by three grains, the other by four grains.

Without a velocity reading, you are relying solely on "pressure signs" to determine if your load is okay & your brass is showing ejector marks & heavy bolt lift. Those ARE pressure signs!

Without a chronograph, I'd suggest you stay at or below book max (66 grains of H1000 with 160 grain cup/core-type bullets.) You can get a chronograph for $155. Much cheaper than a blown up gun & E.R. visit:

Competition Electronics ProChrono DLX Bluetooth Chronograph

The next generation of the ProChrono model based on a time proven design that has been measuring “almost anything that shoots” since 1985!...

www.midwayusa.com

You know something is up & not right or you wouldn't have posted. That was smart. Now you need to listen to people that have been there, done that, & got the T-shirt. That'd be really smart. Stay safe & it'll still be fun! Good luck.

This is the best advice. There is NO substitute for SAFETY, SAFETY, SAFETY; we all know Murphy does NOT discriminate.

 

[Seabeeken]

70 gr H1000 and 160AB show as over pressure

 

[Seabeeken]

The Retumbo berger load is good but could be over due to an almost complete lack of load details for a more accurate calculation

 

[Tulsa Reiner]

Lots of valuable points made above.
I pay more attention to primer cratering and especially flattening, than to ejector marks.
Also, there are degrees of a "sticky" bolt. My Christensen 300 WM always has a little bolt click, which I ignore.
But when I can't lift the bolt without tapping it hard with the heel of my hand, I know I'm over pressure and back off.

 

[Doom2]

Hard bolt lift and ejector marks are a sure sign of overpressure. Hard bolt lift is usually in the 70KSI range.

 

[RPrice]

Looks like obvious over pressure signs to me You're getting good advice to reduce the load.

 

[Mike6158]

Already been mentioned (more than once) but 69.5gr of H1000 with a 168 Berger is max according to the Berger load data. I've been developing a load for my Sendero (7mm Rem Mag) that uses a 150gr TTSX and H1000. The top end of that test is 67.6gr.

 

[dogz]

Speeds?

Couple of us have asked the speeds you're running, please check in and let us know the speeds of these loads. This day and age I can't imagine anyone not running a Chronograph when one can be had for $100 or so.

Keep in mind, no matter what you think your brass is telling you is that "pressure equals speed and speed equals pressure"...

So, please tell us the speeds of these loads

 

[chav0_12]

I've seen plenty of factory ammo brass come out of a Christensen that looks like that. To me it just looks and sounds like a typical CA chamber.

 

[fmuguira]

Get that velocity reading as others have said. That will tell you much!

 

[sturner]

Flat primer and cratering shows pressures
No matter the speeds your rifle tells you what you need to know
You don't need a chronograph to tell you that your load is hot

 

[Pdyson]

These are hot loads at and over book max. The Retumbo load is compressed. You didn't mention working up to these loads. Starting at max is pretty risky. I think if you had worked up these loads, you probably would have stopped earlier. I have seen soft brass cause sticky bolt lift at reduced charges before In my 28Nos complete with deep ejector marks, brass shaving sticky bolt lift, and super loose primer pockets. I pulled bullets and started over twice. My velocity data proved to me that an overcharge was impossible and a brass change was the fix.

going forward, even if you only shoot one round per charge weight over a chronograph in .2 or .3 grain steps (like the 10-shot satterlee), I think you should.

 

[dustbag]

In my experience christensen pressure early. Your primers show beginning of pressure. I wouldn't pay too much attention on the brass markings. Christensen double ejector is stiff and ive seen marks on very low charges especially in softer brass. Buddy has 30 nowler and 7 mag in same gun. Both are border line unsafe with factory nosler ammo. Id back off 2 grains and work up from where you are

^This. All my Christensen rifles pressured out in middle of book range. Way earlier than any of my factory Remingtons. CAs also leave ejector marks early too. I'd back off the charge and run them over a chronograph to know better where your at.