Reloading pressure sign help? CA 300 wsm

[jerm8352]

I have a Christensen Arms 300 wsm Ridgeline Fft. I have about 70 rounds down it. Did the 50 rounds break in they say to do. Didn’t notice any issues doing those 3 boxes of federal premium 200 eldx. Bought some brass. Hornady was all I could find but thought that would be ok using their load data and bullets. Worked up some loads with the virgin brass and went to find velocities and pressure. Starting getting double ejector marks very early. Using 57 grains of Win 760 with a 200 eldx started seeing them. Fired a factory round and noticed it too. Hornady book says 62.1 grains in the max so I am way down from pressure supposedly. Velocities are about where they should be with the 20 in barrel. Fired a few more with varying more amounts of powder and got the same thing. Had a hard not bad but not normal bolt lift but then the next higher was fine. Stopped at 60 grains. The 57 and 60 are picture below on the right and the factory on the left. Tried some accurate 4350 with 165 cx again way under book max with same thing. Tried win 760 with 165 cx and same thing although those were faster than I expected for the load but still way under book max load and max velocities. Am I missing something? Is it the Hornady brass? I’m kinda lost. Any help would be appreciated.

 

[Ram94]

Might be worth sending that one in for a checkup. Those are some heavy pressure signs.

 

[Andouille]

I get light ejector marks with factory WSM ammo and also Norma brass (but not ADG brass), so those themselves wouldn't concern me. But the cratered primers you have are a sure sign of pressure. Hard to tell from the photos if the primers are also flattened, which would be expected if they are cratered.

I'm a newer reloaders, but from my reading of a couple books I gather that pressure signs from regular loads means that your bullets are jammed in the lands, suggesting your chamber has a short throat. Not sure if a too long or short headspace could cause this type of pressure.

 

[Axlrod]

I had a CA in 28 Nos. did the same thing. Couldn't get anywhere near max charges without heavy bolt lift/eject. marks. Sent it back, they put a new barrel on it and I sold it. Had a custom built with a Bartlein carbon. I think they turn the barrels down pretty thin, then when they wrap them, some get distorted. Don't know that, but I do know I will never have another.

 

[SDHNTR]

I bought some once fired factory ammo 6.5prc Hornady brass from a guy here during the component shortage. Two big bold ejector marks on every piece. Asked the guy about his rifle, Christiansen, and he said he could barely open the bolt after each shot. He had no idea that was abnormal. He screwed me, unknowingly.

 

[wind gypsy]

Sounds like a Christensen.

New Rifle Pressure Questions

I recently purchased a Christensen Arms Ridgeline in 300 wsm. Doing their recommended barrel break in of 50 rounds, I bought a 20 rnd box of 165 Norma Oryx, a 20 rnd box of Armscor 165 NAB, and I loaded 10 rnds for a pressure test for future load development. I followed their break in...

rokslide.com

 

[TaperPin]

You might back the sizing die out a full turn and try the same load a few times in the same brass. If your headspace is a little long, the case head slams against the bolt face and can make a serious looking ejector mark without super high pressures. The edges of your primers aren’t super flat. I’ve had some near max loads that left ejector marks almost like that, but still lasted for ten reloads before the case head began to show a separation ring. Harder brass like Lapua might be worth investigating, if any is floating around out there.

 

[jerm8352]

You might back the sizing die out a full turn and try the same load a few times in the same brass. If your headspace is a little long, the case head slams against the bolt face and can make a serious looking ejector mark without super high pressures. The edges of your primers aren’t super flat. I’ve had some near max loads that left ejector marks almost like that, but still lasted for ten reloads before the case head began to show a separation ring. Harder brass like Lapua might be worth investigating, if any is floating around out there.

The silver brass is factory stuff and the Hornady is virgin never fired. I didn’t size the new brass

 

[jerm8352]

Thanks for the replies. I won this rifle but I really like the feel and how it balanced with the short barrel and a suppressor but I guess there is a reason people say to stay clear of CA

 

[TaperPin]

Thanks for the replies. I won this rifle but I really like the feel and how it balanced with the short barrel and a suppressor but I guess there is a reason people say to stay clear of CA

I know the feeling - a 338 was like that. Every powder, every bullet, maxed out early 100 fps slower than my friend’s gun. I eventually got over the disappointment and stopped thinking about it, but it took a few years. Lol

CA has great machining - the rifles look great on the outside, and the chambers look as nicely cut as custom barrels.

 

[jerm8352]

I went back and looked at all my factory brass and only some of it has the marks. Weird.

 

[BCsteve]

Could be a rough cut or burr around the ejector holes. Ejector marks are usually a sure sign of over pressure but the primer edges look good.

 

[Mike D Texas]

Could be a rough cut or burr around the ejector holes. Ejector marks are usually a sure sign of over pressure but the primer edges look good.

Or excessive headspace as mentioned earlier.


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[BCsteve]

Or excessive headspace as mentioned earlier.


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Excessive heads pace will usually have real flat primers from the primer backing out and the case slamming back on the bolt face and on the backed out primer.

 

[jerm8352]

Why would it be on some of the factory brass but not all?

 

[SDHNTR]

Why would it be on some of the factory brass but not all?

Inconsistent headspace due to brass inconsistency

 

[jerm8352]

Sent them an email Thursday night and they haven’t replied yet so we will see how it goes.

 

[SDHNTR]

I’ve seen tight/short chambers pressure up early and result in ejector marks too. Call them. Not email. IME, emails sent to companies in the firearm industry are about 50/50 at best for a response. They should be quite used to this stuff by now. If, by chance you could come up with a .006-.008” variance go/no go set and give it a try, that would give you valuable info. Or at least a field gauge. How much is your brass growing on fired brass?

 

[eschafer]

can someone clarify how a "double ejector" mark happens? never witness one before.. thanks..

 

[HiMtnHntr]

Clean the crap out of it.