Reloading pressure sign help? CA 300 wsm

[jerm8352]

Interesting. What about it didn't look new? Did he consider CA test firing it?

I don’t remember exactly. He said it when we took the stock off and he saw the spot bedding and thought it was terrible and saw a lot of marks somewhere on the action.

 

[35WhelenAI]

Even if double ejectors show pressure earlier, which I'd need explanation as to why two ejector plunger holes would do that (or are needed, other than marketing...), the primers are cratered with that much of a ridge.

Agree with TaperPin, case head expansion is a great tool that guys don't want to do or know how to do, and simply settle for "traditional" pressure signs that vary greatly from gun to gun. Then they diagnose other's issues from a perspective of a totally different firearm than the one in question.

 

[SloppyJ]

So you said they never saw lube, does that mean you didn't size the new brass? You also didn't measure it? I would get a set of hornady gauges and measure the headspace on an unfired round and then shoot it and see how much it grew. While you're at it, get the comparator set and figure out how far the bullet needs to be pushed out to hit the lands. I think this will give you some good info on your rifle/chamber.

 

[jerm8352]

So you said they never saw lube, does that mean you didn't size the new brass? You also didn't measure it? I would get a set of hornady gauges and measure the headspace on an unfired round and then shoot it and see how much it grew. While you're at it, get the comparator set and figure out how far the bullet needs to be pushed out to hit the lands. I think this will give you some good info on your rifle/chamber.

Brass never saw lube. I’m willing to accept I may have screwed something up but the factory ammo doing the same thing is what concerns me. I don’t want to spend more money on this gun. $60+ just to buy another box of ammo

 

[SloppyJ]

If you plan to reload, you need these tools anyway. I wouldn't load precision rounds without them. I think you can take your existing items and load up a couple rounds and see what is going on. Shouldn't put you out any money specifically to this gun, just for reloading tools that you need and don't know it yet.

I wasn't trying to call you out man. I was just putting 2 and 2 together based on what I read. When I started I was the same way. I've learned a ton since then and prep all of my new brass before I fire it just for consistency. I take good measurements and record all of that information because you never know when you'll want it.

 

[jerm8352]

If you plan to reload, you need these tools anyway. I wouldn't load precision rounds without them. I think you can take your existing items and load up a couple rounds and see what is going on. Shouldn't put you out any money specifically to this gun, just for reloading tools that you need and don't know it yet.

I wasn't trying to call you out man. I was just putting 2 and 2 together based on what I read. When I started I was the same way. I've learned a ton since then and prep all of my new brass before I fire it just for consistency. I take good measurements and record all of that information because you never know when you'll want it.

I didn’t take it that way at all. I have the comparator and was using it for the reloads. I’m not worried about the reloads. I can accept that somewhere I didn’t do a good job. But the factory is what unsettles me and knowing what I know about CA from here and other places doesn’t give me piece of mind when they send it back saying everything is fine.

 

[Harvey_NW]

I didn’t take it that way at all. I have the comparator and was using it for the reloads. I’m not worried about the reloads. I can accept that somewhere I didn’t do a good job. But the factory is what unsettles me and knowing what I know about CA from here and other places doesn’t give me piece of mind when they send it back saying everything is fine.

Measure as close as you can at .2" above the case head and confirm it's not less than .555" (SAAMI min). As I mentioned earlier, a tight chamber can cause pressure issues, a go gauge is measuring headspace so the bolt will close fine on a gauge.

 

[willfrye027]

My buddies Christiansen shows ejectors on factory ammo, and reloads pressure out 100-150fps sooner than other 7mm mags I’ve loaded for. But, it is a nice handling and accurate rifle. I load it below where there’s any bolt lift and it’s working just fine. Not a huge fan of the rifle myself, but he likes it.

How’s it shoot? If it’s 100fps slower than it should be, who cares.

As mentioned above try reloading a single piece of brass over and over until the picket is loose. If it lasts a more than a handful of firings..run it.

 

[Don Fischer]

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.

Wrong! Those cratered primer's are probably caused by a loose firing pin hole in the bolt! If that was pressure the primer would be flat all the way across!

 

[Packmansion]

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.

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I've had cratering occur on very light loads. What I read was that this can be caused by loose tolerance between firing pin and bolt. From what I have read heavy bolt lift is your best indicator for an overpressure load. Think is your primers are looking very round not flat at all which is strange.