New rifle - Cooper 92 Backcountry

treillw

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So I'm pretty sure I'm going to get a 300 win mag Cooper 92 backcountry to use as an elk etc hunting rifle. Planning on putting a March 3-24x52 on it for a relatively lightweight package. I have a few questions and would like to plan some things out before pulling the trigger on the purchase.

Does anybody have experience with shooting heavy high bc bullets out of it? I'd like to use 215 berger hybrids or the 212 eldx. I don't think it will have any trouble mag feeding bullets touching the lands. Cooper told me that the mag box is 3.660". Judging from a different gun, I had the bullets loaded to a 3.625" coal - I know that's not an exact science, but in the right ballpark. Those bullets measured 2.856" to the ogive. Cooper said that it's a Sami spec chamber measuring 2.794" from bolt face to ogive. Based on my limited knowledge of the subject, it sounds like I can get the bullets to mag feed while touching the lands. Correct?

Second question. I'm considering having Cooper Cerakote the rifle. They charge $360 plus around $200 to have a finished gun broken down and reassembled for Cerakoting so I don't have to wait 6 months. Would you have Cooper do the Cerakote work, or somebody local? They said it doesn't void the warranty if somebody else does it, but I didn't know how that may change tolerances of bedding the rifle, etc. Also wondering if it is worth Cerakoting Stainless rifle? Does it improve corrosion resistance much? It would be nice for 10 day hunts without oiling the gun.

Has anybody mounted a pic rail on the stock for a modular evolution bipod? Any mounting troubles? Any recommendations on a rail with sling attachment point?

Has anybody replaced their break with a side discharge break for shooting prone? Suggestions on breaks that wouldn't look ridiculous? 1/2"x28" thread.

Last question! What ring setup would be best for mounting the March? What rings and rail (if necessary) would you recommend?

Thanks for help with any of my many questions! I appreciate it!
 
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Your logic seems sound for mag feeding 215s but I wouldn't be 100% confident until I measured the lands in one.

1/2" threads seems pretty small for a 300wm. A lot of gunsmiths wont go that small on a 30 cal bore. I'm not aware of any really thin side port brakes but some gunsmiths will turn one down to match barrel contour.

That seems awfully high $ for a cerakote job, I'd avoid it or look elsewhere.

I've had the march scope you're after and the insanely finicky parallax was a deal breaker for me on a hunting rifle. I took a $900 bath selling it a few months after I bought it.
 

KINGSNAKE

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I had GAP cerakote my rifle. Quick turn around excellent job. I have Talley lightweight mount on my rifle. I like them almost as much as I like DNZ mounts.
 
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treillw

treillw

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Look at a terminator T1 for the brake.

Thanks! The brake looks really good. Is it as good as their videos proclaim? Taking the .300 RUM down to a .243 is pretty impressive. They publish in the comments below that the RUM weighs 7lbs and the .243 weighs 6lbs, so there is a bit of a bias there, but still impressive.
T1 Terminator Muzzle Brake on a 300 Remington Ultra Magnum compared to the recoil of a 7 08 & 243 - YouTube

Is the terminator terrible for the shooter for noise?

I shot a .308 Kimber mountain ascent this weekend and I was surprised at the recoil shooting 178 grain eldx factory loads. Are the Kimber breaks noted for not being as effective as other brakes?
 
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treillw

treillw

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For anybody else reading this in the future, I'm pretty sure that the 215 bergers will mag feed while touching the lands.
http://www.bergerbullets.com/pdf/Quick-Reference-Sheets.pdf

Based on this PDF, the base to ogive dimension for the 215 is .799".
The overall bullet length is 1.598".
Therefore it is .799" from the ogive to the tip of the bullet. (It's funny that the ogive is at the center of the bullet, I assume that is by design??)

Cooper said that their bolt face to ogive dimension is 2.794".
Add .799" onto that for the ogive to tip and you've got 3.593" for an approximate COAL while touching the lands.

Cooper said that their mag box is 3.660".
This gives you .067" of fluff in the mag box, so they should be fine.

Any flaws in my logic?
Thanks!
 
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Thanks! The brake looks really good. Is it as good as their videos proclaim? Taking the .300 RUM down to a .243 is pretty impressive. They publish in the comments below that the RUM weighs 7lbs and the .243 weighs 6lbs, so there is a bit of a bias there, but still impressive.
T1 Terminator Muzzle Brake on a 300 Remington Ultra Magnum compared to the recoil of a 7 08 & 243 - YouTube

Is the terminator terrible for the shooter for noise?

I shot a .308 Kimber mountain ascent this weekend and I was surprised at the recoil shooting 178 grain eldx factory loads. Are the Kimber breaks noted for not being as effective as other brakes?

Yep they are that good. And my opinion is that a 300 win mag is going to damage your ears anyway, and you should be wearing hearing protection already.
 

luke moffat

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I have shot 212 ELDX out to almost 1100 yards with a Cooper 92 in 300 WM. H-1000 seemed to work best.
 
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Thanks! The brake looks really good. Is it as good as their videos proclaim? Taking the .300 RUM down to a .243 is pretty impressive. They publish in the comments below that the RUM weighs 7lbs and the .243 weighs 6lbs, so there is a bit of a bias there, but still impressive.
T1 Terminator Muzzle Brake on a 300 Remington Ultra Magnum compared to the recoil of a 7 08 & 243 - YouTube

Is the terminator terrible for the shooter for noise?

Yes. No free lunch, terminator brakes are effective because they have a steep rearward angle of the ports which in turn directs the percussion rearward. Worse for people to your side but still not nice for shooters.
 
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treillw

treillw

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Yes. No free lunch, terminator brakes are effective because they have a steep rearward angle of the ports which in turn directs the percussion rearward. Worse for people to your side but still not nice for shooters.

Is the noise bearable with plugs and earmuffs?
 
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treillw

treillw

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For those of you that have .300 win mag M92s, how would you describe the recoil with a brake? What type of brake do you have?
 

Glarg

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How has your experience been with the new brake etc? I got mine a few months ago and factory settings have been good. I dont like the mag much but maybe that needs break-in.
I put a suppressor on mine for a bit and although I had to re-sight the scope for it, I was getting super nice groups, minimal recoil and noticeable sound dampening for my spotter.
 
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