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Cooper 92 6.5-284 gaining accuracy

I had to send my rifle in also, I haven't even fired it yet. I started getting corrosion on on the top of the bolt and after I would dry fire it the bolt lift was very stiff. When I talked to Cooper and told them about the corrosion they said they were aware of it and had changed the finishing process. They said it was a fairly common issue. Then I told them about the very stiff almost difficult to open bolt and they said that is a less common issue and then they sent me a UPS call tag. I sent if off a couple days before Christmas and I don't have it back yet.
 
I had to send my rifle in also, I haven't even fired it yet. I started getting corrosion on on the top of the bolt and after I would dry fire it the bolt lift was very stiff. When I talked to Cooper and told them about the corrosion they said they were aware of it and had changed the finishing process. They said it was a fairly common issue. Then I told them about the very stiff almost difficult to open bolt and they said that is a less common issue and then they sent me a UPS call tag. I sent if off a couple days before Christmas and I don't have it back yet.

Sounds like my 6.5 x 284 Cooper. I am just now prepping brass but the bolt is VERY HARD to lift after dry fire - ? normal. Have you gotten your rifle back yet? What did Cooper say? I really want to start shooting in stead of sending to Cooper!
 
Maybe I haven't paid a lot of attention but this is the first time I've heard a lot of problems about their rifles. Is their quality control slipping?
 
Did you check the bottom base plate of the magazine make sure it didn't slide forward. If this is the issue, it's easily fixed. It's only press fitted and if it creeps forward this will cause the rounds to miss-feed and get dented. It a poor design, but easily remedied by opening the bottom lips with a needle nose pliers for a tighter fit.
Don't think so, but I will check again. The fluted bolt is what hits the 2nd round in the magazine, the first or top round goes into chamber fine. You can see the fluted bolt ridges on the neck and shoulder of the 2nd round in the magazine. Sounded like they knew what was wrong and have a new bolt design.
 
Don't think so, but I will check again. The fluted bolt is what hits the 2nd round in the magazine, the first or top round goes into chamber fine. You can see the fluted bolt ridges on the neck and shoulder of the 2nd round in the magazine. Sounded like they knew what was wrong and have a new bolt design.

May not be the issue, but it is the symptom of the magazine problem I described. The bullet gets cocked in the magazine. It's easy to check out.
 
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Don't think so, but I will check again. The fluted bolt is what hits the 2nd round in the magazine, the first or top round goes into chamber fine. You can see the fluted bolt ridges on the neck and shoulder of the 2nd round in the magazine. Sounded like they knew what was wrong and have a new bolt design.

Here are some pictures of the problem I am having with the denting of the brass. Happens to the 2nd bullet in the magazine, after the top one is taken to the chamber.
You can see the fluted bolt ridges in the brass. The bottom plate does move forward very easily too and could cause issues as well.
 
As a big fan of 6.5-284 and a big fan of coopers ( I have 5 ), I thought I would log in an give my once a year opinion. Firstly, I find all their barrels to be accurate but lower velocities and pressure signs before I near max loads. All can shoot 5 shot 100 yard groups under 0.75" with a load it likes.

I was fortunate with my 6.5-284 Cooper Phoenix to quickly find a load with 142 gr SMK and R22 that would repeat groups 0.3 to 0.4" when I kept the bullets seated 15 thousandths off the lands. I did not notice but I hope you are using Lapua brass. I have over 1500 rounds through the barrel and no degradation in accuracy....yet...but I know it is coming.

Where I will switch my direction is your comment on using Berger. I shoot F Class and just put my 5th barrel on my 308. I have found Berger bullets extremely accurate once you test the "bullet jump" for your barrel. I have had barrels that like 5 thou and some that like 30 thou. All cut with the same reamer on Kriegers. My opinion is to experiment with jump once you have measured OAL to lands with a great tool like Sinclair. My tool is 20 years old but I am sure you can still get one.

I hope you get yours to shoot well. Copper makes an outstanding product and stands behind them.

Your shooting friend from Canada.
 
Iv just picked up a cooper M92, the underside of the bolt has been machined flat where it rides over the rounds in the magazine.

I should have my 92 by the end of the week curious to see if mine has the same milling under the bolt.
 
When did you send your rifle in? I still haven't gotten mine I'll give him a call this week out of curiosity.
 
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