Cartridge Guage and Chamber Fit

DocRDS

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Feb 21, 2012
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So i had trouble with my first batch of reloads on my 308, some did not chamber. Whilst trying to troubleshoot this I found that my some of my rounds will not fit my cartridge gauge, but some WILL chamber in my rifle. In fact, they stick out 1/4 inch from the gauge. That seems like quite a lot, so I am not sure how they can be so out of whack and yet chamber fine (the headspace is long in some which is why the bolt won't close). Even if the headspace is off--that measurement is SUPER small compared to a quarter inch!

So I have once fire brass (mixed headstamp) that will chamber in a 308 but NOT in the cartridge guage, and stick out by about 1/4 inch--what is going on? If my headspace is off, I would expect them to be slightly "non-flush" not obviously sticking out in the guage. Rifle is a Rem 700 circa 2003-ish.
 

2aBaCa

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Sounds like the die didnt resize the body of the case all the way. You might not feel it when closing the bolt in the action. If you strip the bolt you would probably feel the resistance.
 

ditter

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Your fired brass will not go into a chamber gauge and will stick out a significant amount if the body is not sized fully, particularly the case head. It will almost always go into the chamber of your rifle since it was fireformed to that chamber. The ammo checker is measured to SAAMI specs, which is why a factory round will go in it easy, while fired brass will stick out. Best thing to do is measure your fired brass against a factory round. See where your big measurements differences are and adjust your die accordingly. I'd suggest that if you're just starting reloading, try to have your sized brass match the measurements of a factory round.
 
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DocRDS

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So when I first found this, i did resize a few bad ones and they would measure (Sit flush in guage) after I cranked down the die to "Factory" setting rather than bumping .002 (or at least my attempt at .002) , so my die must of been pretty far off. but yeah I borked this one pretty hard it sounds.

edit: thx ditter, I'll go get my calipers--I did go back to just "vanilla" reloading until I understood this screw up. I tried and tried to figure out where the mismatch was with a marker and chambering the round and it just wasn't showing me anything.
 

AllenOne1

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What case gauge and die are you using? I had a very similar issue with a Hornady case gauge and a Redding full length die. They would chamber fine and shoot well but would never fit in the case gauge. I have a whole thread outlining my sizing issues this year so I'm no expert on this subject.

What is bothering me is that you are saying "some" will chamber in your rifle. That makes me thing that you are not getting them fully sized, are you sure the shoulder is being moved back .002? How are you measuring that?
 

DocRDS

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Its a Hornady case guage and Redding FL die!. I used a headspace comparator to measure the first few. Somewhere in the middle my die got readjusted out of spec and I didn't get it back correctly. Thats where the "bad" rounds came from. I kinda went in two sessions--session 1 was ok, session 2 produced the bad rounds.

Since I had some mixed brass, my suspicion is the bad rounds came from a different rifle, while the "good" rounds came from the rifle I was shooting out of. Thus if was doing 0 sizing from poor adjustment, the fire formed rounds fit tight, but fit, the other rifle brass was larger than chamber and thus would not feed. That's my working theory anyway.

ALso segregating brass by "match" and "other/semi-auto". Many noob mistakes but its better than sittin playing computer games.
 
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AllenOne1

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Mar 8, 2020
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Its a Hornady case guage and Redding FL die!. I used a headspace comparator to measure the first few. Somewhere in the middle my die got readjusted out of spec and I didn't get it back correctly. Thats where the "bad" rounds came from. I kinda went in two sessions--session 1 was ok, session 2 produced the bad rounds.

Since I had some mixed brass, my suspicion is the bad rounds came from a different rifle, while the "good" rounds came from the rifle I was shooting out of. Thus if was doing 0 sizing from poor adjustment, the fire formed rounds fit tight, but fit, the other rifle brass was larger than chamber and thus would not feed. That's my working theory anyway.

ALso segregating brass by "match" and "other/semi-auto". Many noob mistakes but its better than sittin playing computer games.
Doc
I had the exact same experience using a Hornady case gauge and Redding FL sizing die combination. If you can get the shoulders bumped back a couple of thousands and if it will fit in your chamber smoothly throw the case gauge in a drawer and forget about it.
 

AllenOne1

Sergeant of the Hide
PX Member
Minuteman
Mar 8, 2020
130
53
Its a Hornady case guage and Redding FL die!. I used a headspace comparator to measure the first few. Somewhere in the middle my die got readjusted out of spec and I didn't get it back correctly. Thats where the "bad" rounds came from. I kinda went in two sessions--session 1 was ok, session 2 produced the bad rounds.

Since I had some mixed brass, my suspicion is the bad rounds came from a different rifle, while the "good" rounds came from the rifle I was shooting out of. Thus if was doing 0 sizing from poor adjustment, the fire formed rounds fit tight, but fit, the other rifle brass was larger than chamber and thus would not feed. That's my working theory anyway.

ALso segregating brass by "match" and "other/semi-auto". Many noob mistakes but its better than sittin playing computer games.
It sounds like you are getting things figured out correctly. Keeping brass with the same gun it was fired in will make a big difference, you will need two sizing die setups though one for the bolt gun and another for the semi auto unless you are comfortable sizing for the semi auto and just running it in the bolt.
 

DocRDS

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Feb 21, 2012
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Doc
I had the exact same experience using a Hornady case gauge and Redding FL sizing die combination. If you can get the shoulders bumped back a couple of thousands and if it will fit in your chamber smoothly throw the case gauge in a drawer and forget about it.
Its good to know someonw else finds these things. I'm always WTF just my luck.