6.5 PRC over pressure issue

806guns

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May have a issue here.
Using Peterson brass 53gr of h1000 got me 2890 fps with hard bolt lift. 156gr Bergers

Running 20 thou jump

Remage barrel set using go gauge and no go gauge. Not my first remage barrel setup.

What measurements can I do to see where my problem is. When chambering a new round it's smooth as butter.
Brass or chamber issue?

Using the hornady comparator tool. Shoulder grows .004-.005 on this piece of brass vs new brass.
Heres a picture of the chamber
1000010134.jpg
 

waspocrew

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How many firings on the brass? If it's multiple, you may be having clicker issues.

Are you getting ejector swipes and/or flattened primers along with the bolt lift?
 
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806guns

806guns

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New Peterson brass barrel has 200 rounds down it when I got it.
Shot 1 hornday 147gr eldm round. Slight bolt lift issue reading 3017 fps 1000010144.jpg
 
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806guns

806guns

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Peterson load 54.5 gr h1000 with wolf magnum primers.
156gr bergers set .050 off lands thus load is suppose to be around 2644 fps not 2978!!!
1000010142.jpg
 
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806guns

806guns

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This is what the chamber looks like.
2nd picture is with a new piece of Peterson brass in the chamber.
Used a go no go gauge to set headspace with ejector removed.
1000010134.jpg1000010139.jpg
 

Shortschaf

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is what you are seeing just the "clicker" prc issue? If so, Alex Wheeler's PRC reamers have been known to fix

Only other thought with the limited information is to slug the barrel and see if it is a touch tight

the firecracking in freebore pics looks pretty normal to me
 
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806guns

806guns

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is what you are seeing just the "clicker" prc issue? If so, Alex Wheeler's PRC reamers have been known to fix

Only other thought with the limited information is to slug the barrel and see if it is a touch tight

the firecracking in freebore pics looks pretty normal to me
When loaded to the Berger load data it locks the bolt and is hard to open. 😳
 

TaperPin

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Is this barrel new to you? Not all used barrels are problems, but all problem barrels end up being sold used.

Some barrels have a bore that’s slightly undersize and they just create pressure sooner. I had one and it drove me nuts never being able to shoot anywhere near published max loads, and was over 100 fps slower than a typical gun of that cartridge.

If the chamber is rough or lacks much of a taper, that could be contributing to hard bolt lifts. The ejector mark wouldn’t bother me, unless the case will only reload 6 times before loose primer pockets, or partial head separation.
 
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806guns

806guns

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Is this barrel new to you? Not all used barrels are problems, but all problem barrels end up being sold used.

Some barrels have a bore that’s slightly undersize and they just create pressure sooner. I had one and it drove me nuts never being able to shoot anywhere near published max loads, and was over 100 fps slower than a typical gun of that cartridge.

If the chamber is rough or lacks much of a taper, that could be contributing to hard bolt lifts. The ejector mark wouldn’t bother me, unless the case will only reload 6 times before loose primer pockets, or partial head separation.
Barrel is new to me yes. Previous owner said he was getting 156 at 3k with rl26.
 

TaperPin

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It seems you’re pretty close to what would be expected. RL26 often outperforms H1000 by a little. Unfortunately we probably won’t see RL26 for at least a few more years.
 

TaperPin

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Barrel is new to me yes. Previous owner said he was getting 156 at 3k with rl26.
I had to reread the previous posts - now I see how I misunderstood what you were saying. So, you’re concerned it seems like you are 300 fps faster than you should be. Powder lots differ, no two barrels are the same, publish loads vary all over the place, so you might be in a normal range of variability, or not.

The thing that jumps out as something to check is neck clearance. If the chamber has a tighter than normal neck, normal brass might be barely releasing the bullet, driving pressures and velocity up. It’s often said if the neck is too tight for the brass a bullet won’t drop freely through the neck of a fired case.

If headspace is even close to correct, the barrel is clean, good brass, chamber is close enough to not have a tight neck, bullet isn’t jammed, then I would think you have what you have.
 
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