Fired good at first so it must be a sizing issue.
Hard bolt Lift
- Thread starter martyj
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Rich Coyle
Well-Known Member
I had unexpected pressure with my 7-.338RUM. The problem was the necks grew so much they pinched on the bullets. Trimmed the brass and pressure returned to normal.
Harry Knutz
Well-Known Member
If you already have a case trimmer such as a "Forster" Then reaming is more economical, And there is less chance of mistakes. I used to ream necks but I turn mine now, Just make sure if you ream them, That the case has either been fired or expanded. And if you decide to turn, Make sure you start out with a couple of extra pieces to get your tool set right.
When you neck down, All the brass gets squeezed into a smaller area and it becomes too thick. You can get away with it when you neck up.
Harry Knutz
Well-Known Member
Yes, I have also experienced this problem too. But I think the necks are too thick in this case.
JustMe2
Well-Known Member
Do you mean "Action Cleaning Tool Kit"?
Action Cleaning Tool Kit - Bore Tech Gun Cleaning Tools
Designed for meticulous cleaning of a bolt action rifle’s chamber, locking lug recess and action. Order an action cleaning tool kit for your gun today!
After first firing, you will find brass swells a lot to fill your chamber. Plan on reducing load for second firing. Many folks have noted this. Prep for second firing will require you to trim the cases as they will undoubtedly stretch. Are you full length resizing your brass? If not, you may find this to required. Personally, I use full length/neck resize on all my brass and check/trim a/r on all used brass. Every time. No exceptions. No problems. Works great for me.
Stay safe and have fun.bigngreen
Well-Known Member
You need to get the reamer specs used so you can accurately measure what's going on.
Typically with this much neck down on that case you need to neck turn at 338 to end up where you need to be as the brass thickens with sizing down.
Need to know the neck diameter, base diameter and case trim length before pulling the trigger, this is a big case necked down about as much as you want, it can go bad wrong fast!!
Typically with this much neck down on that case you need to neck turn at 338 to end up where you need to be as the brass thickens with sizing down.
Need to know the neck diameter, base diameter and case trim length before pulling the trigger, this is a big case necked down about as much as you want, it can go bad wrong fast!!
I have worked with this 7-338 improved case quite a bit in the last couple of years. The first reamer I purchased I sent the reamer prints in to get sizing dies made. They did not work so well. They were not sizing the case down in the web area enough so no matter what load I used I had clickers and hard bolt lift. The second reamer I ordered I changed some case dimensions and had a sizing reamer made so I could make my own dies. Problem solved. I would check the necks. They may have to be turned a bit but my guess is that your dies are not sizing the web area down enough. Measure a fired case at the web and a sized case and see how much it is sizing it down. The problem may be your dies not sizing down enough?
This ^^^^is where I would look. .338 necked down to .284 is quite a bit. I bet necks are to thick
BrentM
Well-Known Member
Yes. CorrectDo you mean "Action Cleaning Tool Kit"?
Action Cleaning Tool Kit - Bore Tech Gun Cleaning Tools
Designed for meticulous cleaning of a bolt action rifle’s chamber, locking lug recess and action. Order an action cleaning tool kit for your gun today!www.boretech.com
Stonyman88
Well-Known Member
Have a issue with a friends 300 PRC, you almost have to pound the bolt down to get it to close into battery, then after you shoot it , well think ya ll know, almost two hands to open it and eject the round. Not good, I told him I would take this custom $$$$ price gun back to who sold it and have then sent it to the builder. Plus at 300 yd it can't shoot under a 15" group. Just for my info, any one have a idea what it could or may be. These were all new boxed Win ammo, 300 PRC 212 or 225, gr I believe on the gr.
I did check the shoulder and they seem to be OK, not jammed or dented, but if you ever need a back up shot , well good luck cuz you'll have to get up with both hand to eject a round.
I did check the shoulder and they seem to be OK, not jammed or dented, but if you ever need a back up shot , well good luck cuz you'll have to get up with both hand to eject a round.
Not properly chambered
Mike Matteson
Well-Known Member
Take your dimensions before and after firing the case. Again after sizing the case. Annealing sets the hardness in the neck area if done correctly. So your release of the bullet is closers to the same each time. That's a good thing.
BrentM
Well-Known Member
Sounds like the chamber wasn't cut right. I assume you don't have a go or no go gauge. The fact it won't close on a factory round makes it seem like the chamber isn't right at all.
