6mm Magnum vs 6 CM +P

Thejet

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For what it’s worth, I cut a stock 243 tikka barrel to 15 inches and pinned a brake on then gave it the +P. Could run up at 2950+ but accuracy is in the 2820-2850 bubble for 115 and 108 bullets.
 
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B_Reynolds_AK
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For what it’s worth, I cut a stock 243 tikka barrel to 15 inches and pinned a brake on then gave it the +P. Could run up at 2950+ but accuracy is in the 2820-2850 bubble for 115 and 108 bullets.
Wow that’s smoking. I have a 20” PVA 6 CM barrel that already has 600 rounds on it since November. Maybe after the summer when I’m well over a thousand, I’ll send it to UM and have them +P it for all of our curiosity. I know Ryan’s 6UM didn’t like it, but that’s kind of a different beast than a 6 CM. The risk of having a barrel shit the bed from it would be less when it’s 3/4 of the way through its usable life.
 

brockel

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For what it’s worth, I cut a stock 243 tikka barrel to 15 inches and pinned a brake on then gave it the +P. Could run up at 2950+ but accuracy is in the 2820-2850 bubble for 115 and 108 bullets.
Wow I have a 20” tikka 243 and 108 barely breaks 2900 in it. It’s getting a 6mm prc reamer ran in it here soon
 

Thejet

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Wow that’s smoking. I have a 20” PVA 6 CM barrel that already has 600 rounds on it since November. Maybe after the summer when I’m well over a thousand, I’ll send it to UM and have them +P it for all of our curiosity. I know Ryan’s 6UM didn’t like it, but that’s kind of a different beast than a 6 CM. The risk of having a barrel shit the bed from it would be less when it’s 3/4 of the way through its usable life.
Mine is less/different +P than what UM does.
 

Lawnboi

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.200 plus freebore on the standard pva 6 creed is probably already not far off plus p.

Last 6 creed from pva I got with the short freebore for shooting 105 hybrids. Shoots unreal.
 
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.200 plus freebore on the standard pva 6 creed is probably already not far off plus p.

Last 6 creed from pva I got with the short freebore for shooting 105 hybrids. Shoots unreal.

I thought it was basically just SAAMI'ish which is 183 freebore but 0.200 measured from the full neck diameter portion of the mouth rather than the furthest forward taper of the mouth.
 

Lawnboi

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I thought it was basically just SAAMI'ish which is 183 freebore but 0.200 measured from the full neck diameter portion of the mouth rather than the furthest forward taper of the mouth.
I believe it’s like 210k, not sure on the exact geometry or anything special they did or didn’t do. Looks like a mile in the bore scope. My standard shot very well. I just have a bunch of 105 hybrids and didn’t like the idea of jumping them that much, or running them that fast. For a hunting chamber, shooting 108 eldm, it would be ideal imo. I was loading 110 atips at 2.9” in my standard, and could have easily pushed them well over 3000 in a 26”.

I really just need to abandon the creedmoor for PRS. Hard to justify new dies and such though.
 

Sadler

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Crazy how far even a 16” 6CM is effective to. Such an effective cartridge with high BC bullets.
Couldn’t leave well enough alone and started load development with the 109s, alpha brass, H4350, and 210M primers and OAL is 2.8”. Exceeded my expectations for sure. I loaded up to 42 grains but could have gone farther. No bolt lift and the brass and primers look good. I may push it further next week just to see how close I can get to 3000 IMG_7503.jpeg
 
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B_Reynolds_AK
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Couldn’t leave well enough alone and started load development with the 109s, alpha brass, H4350, and 210M primers and OAL is 2.8”. Exceeded my expectations for sure. I loaded up to 42 grains but could have gone farther. No bolt lift and the brass and primers look good. I may push it further next week just to see how close I can get to 3000 View attachment 713273
Thats sweet. I've only been using recycled Hornady brass as I get started in reloading. Ive been able to get 42.4g of H4350 with moderate pressure signs with that soft brass.

However, I have 100 Alpha LRP brass, H4350 and 210 primers that I will be working up with 112 Match Burners for my new 18" barrel. I'm now confident that I'll hit my 2900 fps goal with 2" more barrel than what your working with.
 
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