Fixing too much shoulder bump

Just seat the bullet into the neck so it will not fall out - as little as possible.. measure before and after chambering... hopefully, it will go further into the case.

Tell me what the bearing surface distance in the case neck is now once you know where the jammed bullet length is. Repeat as necessary to get a repeatable/reliable number. If the bullet is stuck in the rifling when you try and eject the case, THIS IS A GOOD THING. Knock out the bullet, set the seater a bit deeper and try again. At some point the bullet will be jammed into the lands but stay in the case neck when you eject.

From this seated bullet length, set your seater to be 5 thou shorter (or 1/4 turn deeper)... seat, jiffy mark, chamber, eject, any marks on the ogive? Keep seating in deeper until the rifling marks are pretty much gone. Don't be surprised it there used to be several dots on the bullet, then you end up with 1 or at most 2..

This is your OAL to the start of the rifling... how much bearing surface is now in the case neck?

Will this OAL fit in your mag?

NOW, we start to figure out how to load tune.

Jerry
 
wajp

Another way to check how much head clearance you actually have is to use a spent fired primer and start it into the primer pocket just using your fingers.

First take one of your sized cases and measure its length and write it down.

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Now just start a fired spent primer into the primer pocket.

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Now chamber this test case slowly closing the bolt and using the bolt face to seat the primer. Now remove the case and measure the case length again from the primer to the case mouth and write it down. The subtract the first case measurement from the second and this will be your head clearance.

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Now cross check the problem and measure one of your fired cases with the protruding primer and write it down. Now push out the primer and remeasure the case and write it down and subtract the second case measurement from the first to get your head clearance. (a second time)

Now let us know if you actually have .025 head clearance or what measurement you actually have.

And a Hornady cartridge case gauge would tell you a lot about your normal fired cases and the "problem" cases.

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"Headspace" is subjective and only you can tell us if your glass is half empty or half full.

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I know a guy who fired a 30-06 in a 300 WM. He survived but it blew the floor plate off his rifle. His eyes were very blood shot when he got back and told my dad what had happened. He really got a face full of gas.
 
I just checked my cases again with my hornady case gauge:

- Unfired reload 1.733
- Fired reload 1.740
- Fired factory ammo 1.763

So as you can see I'm at 30 thou difference between my chamber and the resized brass, and the one round I fired is still just under 25 thou too short. I'd post pictures but I have no clue how.

As for the seating depth, I have found my lands before in other rifles without issue, it's just that in this one I had the bullet seated past where I felt comfortable with it being and gave up since I still couldn't find the lands. At least with this rifle mag length will never be an issue, it's a Tikka long action and as I'm sure you know the 6.5x55 is more of a "medium" cartridge, with my bullets seated out where they are now I probably have a quarter inch if not more left before I reach 30-06 length.

What is the minimum "safe" bearing length? I've heard the old "at least one caliber length of bearing", which I've never followed and is pretty much impossible in alot of cartridges (300 win comes to mind). I have played around with OAL before but most of my loadings in other calibers have either been to mag length, or to "recommended" OAL in my 257 Wby since Id need to weld 2 bullets together end to end to even think about finding the lands. The Tikka gives me alot more flexibility with the long action but I'm worried the bullet will get knocked out of alignment by the feeding process or pushed back/knocked loose by recoil while it's in the mag if there isn't enough bearing surface, especially if I'm neck sizing with a lee collet and won't have a heck of alot of neck tension to begin with. Is there a rule of thumb for how much bearing I need to avoid these problems?
 
No die set will size to zero clearance with all chambers. If the primer was backed out after firing, you were using low pressure loads. Up the pressure and your result will be different for first firing and on subsequent sizings, you can set up the die as required for your chamber.
 
If he increased his load the brass will attempt to stretch 30 thou to fit the chamber. Case head separation will be the result if he does that, not a good idea for him to continue as it is.
 
Just an FYI for anyone curious, I just got a call from Redding, the problem was my shellholder, it's 25 too short, or at least that's what they're saying. I'm going to have to measure everything and do a test run once I get the dies back to confirm. Excellent customer service btw, not only did they solve the problem, they're giving my dies a thorough cleaning and sending me a free shellholder that is to spec.
 
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