New Rifle Pressure Questions

[erle1139]

Update to my predicament...I tried what many suggested: loaded the same powder string with the Winchester brass and then started at the lowest charge with the Norma brass. Hodgdon’s starting load with staball 6.5 and a Swift scirocco (bullet I’m using) is 61.5 gr at 2720 fps and the max is 66.5 at 3019 fps. I loaded the Norma brass at starting load and increased .5 grain each subsequent
61.5 - 2794 no pressure signs
62.0 - 2855 slight bolt stick
62.5 - 2847 slight bolt stick
63.0 - 2910 bolt stick and ejector marks.
Did up to 65.0 and pressure got worse.

With winchester brass I tried the previous loads from original post, starting at 64.8 and moving up to max load in .4 gr increments.
64.8 - 2954 fps and heavy bolt/ejector marks. didnt bother to continue.

I measured OD of the necks of loaded Winchester (.334) and Norma round (.337) I measured a new Nosler Trophy Grade ammo i just got in today and it measures .338 at the neck. Using digital calipers but taking several measurements.

Fired brass neck OD are both .338-.339. A new bullet will drop into the winnie case on its own, needs some help on the fired Norma case.

I emailed Christensen Arms about my pressure issues last night and this morning they emailed me a Fed Ex label to ship it back. So that’s where its at, we’ll see...

I appreciate everyone’s feedback, this is a new issue for me. Hopefully they can get it straightened out since I’ve been looking forward to this gun for about a year

 

[KGUNSHOOTER]

Any update?

 

[T28w]

Also interested in any updates as I’m feel I have something similar in a tikka 300wsm and Norma brass

 

[erle1139]

Any update?

Received the rifle back about 6 weeks after sending it in. They said they tested it out and had brass get stuck after firing it. They adjusted the head space, polished bolt face, polished chamber.

Finally had a chance to take it out yesterday, still trying to work up a load for it using the Winchester 6.5 staball powder and 180 Swift Scirocco II. Hodgdon website shows max load with this bullet at 68 grains and 3019 fps. I ended up with pressure signs at 66.4 grs and 3060 fps so I stopped there. That's better than pressure issues at 2800- 2900 fps I guess. It actually falls closer in line with the published data for the 180 gr Nosler E Tip bullet.

One issue I did encounter: I have a brand new box of Nosler factory 180 gr E Tips. When I put them in the chamber, I can get the bolt to go all the home, but can't get the handle to close on them. My winchester/norma hand load cases close just fine. I did notice the factory Nosler case from the shoulder to the rim is a little bit longer than my norma brass. I didn't measure the difference, but I can eye ball and see its a little longer. I'm not sure if that's a Nosler issue or still my rifle's issue. I need to measure it out and see how it compares to book specs. It loaded Armscor factory ammo with Winchester cases no problem.

So is it fixed...I'm not sure yet. velocity-wise it's not showing pressure signs until it supposed to, but at a lower charge weight than the book says it should, plus the Nosler factory ammo not fitting into the chamber. I'm not sure what my next step should be besides continuing on with the reloading process, using the velocity and pressure signs as a guide.