Case sizes and resizing

cereal83

cereal83

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Hey all, me again :)


Well I got my digital caliper today and I am just wondering something.

For the 30-06 my Lyman book says the max case size should be 2.494 inches. I measure the cases that haven't been sized with the full lenth sizer die and they are 2.497 inches and the ones I have ran through that sizer and primed are 2.495. I am thinking I should but I don't know if the .1 really makes a differance.

I know max says 2.494 but DOES it really have to be that? What about smaller, is it ok to be a few mm smaller?

Any help is great.

Thanks :dancingbanana:
 
better to be a tad under then over..but im sure .0003 over will not be a prob..when your not sure..of a measurement..always go under what your looking at..get your trimmer out and get rid of the extra bit...if you dont have a timmer.. use a deburring tool to
cut it down a bit..
 
Well I just checked all my shells and only 3 of them were under 2.494 out of 120 cases.

I have both the deburing tool and a trimmer just not the size thingy.

Well I guess I have to do a bunch of sizing. :)


Thanks
 
Dude - You're so missing the point about sizing.... You've been told to try chambering a primed case - the answer to your question lies here, grasshopper.
 
You should never reload overlength cases. The maximum is 2.494. Over this length they need to be trimmed, firing overlength cases can cause the bullet to be jammed tighter into the case neck as the round is chambered as you are now over max length.... this can cause over pressure situations.

There is no close enough when reloading PERIOD Keep things within specs, there are no missed steps, or I don't feel like doing it... its too much work.....

If you don't want to trim your brass then buy factor ammo.... reloading is work, 80 percent of all the work is case preparation, not pouring in powder and seating a bullet thats the easy part. Follow all the steps, measure, and follow the loading manuals and you will not have a issue.

If this all sounds like too much hassle, take up fishing..... the fishing rod doesn't blow up in your face.

DOES YOUR PRIMED CASE THAT YOU RESIZED FIT INTO YOUR CHAMBER OF YOUR RIFLE AND WILL THE BOLT CLOSE WITHOUT USING FORCE????????
 
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Well I just wanted to make sure. I haven't tried putting it in my rifle yet just because I haven't taken my rifle out yet.

I will follow the directions to a tee but I just wanted to ask.
 
Before you load powder and ammo in the cartridge, you have to test the sized empty casing in your rifle to ensure it chambers properly and the bolt closes, that way you will know that your sizing die is set properly.
 
Well I just put 6 rounds into the gun.

2 of the rounds have been fired and thats it. Old primer is still in them and both fit.

2 of them have been resized with the "full lenth sizer" die and primed but are longer then 2.494 they both didn't fit.

2 of them have been resized with the die, primed and are under 2.494 and they both fit.
 
If you try and chamber rounds loaded with cases that are overlength,the case will bottom in the chamber.If you force the bolt closed,the case will then be squeezed against the bullet like a very,very strong crimp.This will cause an increase in chamber pressure.
 
Mauser98 said:
It's really very simple.

If some of the cases in a batch are at or over max length, trim them all back to minimum length.
Click to expand...


Exactly. As soon as I get my other part for my trimming kit, I will do so
 
How do you know its not the case shoulder causing the interference? (read your first post...)
How do you know your newly acquired calipers are accurate to within a thou or two?
If your once-fired cases were all sized at the same time, why do some chamber, and some not?
Using your Lee trimmer, how do you plan to trim the cases with the live primer in-situ? (read previous posts on the subject...)
So many questions... life is not simple at the reloading bench, grasshopper...
 
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I trim all brass to minimum spec when I buy it. I've never found any brass that ever grows to maximum and requires re-trimming. Granted, I only ever neck- or partial body-size
 
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