I've been reading different post on here about resizing 308 brass to 243!, I tried some hornady and federal, I just ran the 308 case through the RCBS 243 FL die and it won't chamber in my gun, it was just a empty resized case no bullet!...... What am I doing wrong?
308 to 243
- Thread starter matt bradley
- Start date
If you used a .308 case that was fired and reloaded before as a .308 case you may be dealing with brass spring back after sizing.
1. Make sure your die is making hard contact with the shell holder and the press is reaching cam over.
2. When the ram is at the top of the ram stroke count to four while letting the case stay inside the die. This lets the brass know who is the boss and you will have far less brass spring back when pausing at the top of the ram stroke.
Also remember we live in a plus and minus manufacturing world and no two chambers and dies are the same. Meaning you may have a chamber on the minus side and a die on the plus side of tolerance. This some times happens to me when I buy once fired 5.56 Lake City cases so the first sizing is done with a small base die to bring the cases back to minimum case dimensions.
Note, when sizing from .308 to .243 your necks will become thicker and grow longer when sized down. Meaning they will need trimming and possibly neck turned to reduce the neck diameter. Tiriaq gave you some very good advice about smoking the case or you can try using a magic marker to find your problem.
They will chamber (just the empty case) but I can't close the bolt all the way!
Hitzy
You are correct, to be truthful I was using Lake City military 7.62 cases and thought they were longer after sizing. My problem may be getting older and my memory getting shorter.
run your cases into a body bump die, depending on what 308 rifle they were shot in the web could be swollen much larger then the chamber of your 243 and hence they will not chamber all the way in, the other option is to lube the base of the case a bit more and go for some serious cam over on the press.
Are you using 243 SMALL BASE DIES????
Are you using 243 SMALL BASE DIES????
There an old set of RCBS I have, I'll take a pic later and post it, it almost looks like the shoulder is to high, I ran in to this problem one other time and just put the die in my lath and took a couple thou off the bottom and its solved the problem!!!! I sold my lath since..... Lol
I got it to chamber!, I smoked the case and put it in the chamber and it was the base of the neck that was stopping me, so I screwed the die in so I could not even cam over and it chambered after, I think I have a tight chamber and a loose die!
I load for .30-06, 9.3x57mm, and .338-06, all using the same pile of old surplus .30-06 LC match brass I'd picked up in a deal many years back.
To minimise confusion, age-related or otherwise, I store each well apart from each other on different shelves in my ammo locker, use different brands and colours of well-marked 50rd ammo boxes for each cal, and only have one of the calibre's components out on the loading bench at any time.
All that as well as the visually different case dimensions and different bullets I usually load in each calibre, I haven't had any problems yet.
To minimise confusion, age-related or otherwise, I store each well apart from each other on different shelves in my ammo locker, use different brands and colours of well-marked 50rd ammo boxes for each cal, and only have one of the calibre's components out on the loading bench at any time.
All that as well as the visually different case dimensions and different bullets I usually load in each calibre, I haven't had any problems yet.
I would just like to point out that on many reloading posts, the words "cam over," is used a great many times, but in reality, it is a misnomer!
When the handle is full down, the ram is ALMOST at top dead centre, but all presses are designed to stop the ram from going past dead centre, or "cam over."
It is the cam action that give presses the great power and the greatest power occurs just before it to top dead centre, where some type of built in stop prevents it from actually going past top dead centre.
If the die is adjusted too far down, the ram will be a considerable distance from dead centre when the handle is full down, and it will have a lot less power on the case.
When the handle is full down, the ram is ALMOST at top dead centre, but all presses are designed to stop the ram from going past dead centre, or "cam over."
It is the cam action that give presses the great power and the greatest power occurs just before it to top dead centre, where some type of built in stop prevents it from actually going past top dead centre.
If the die is adjusted too far down, the ram will be a considerable distance from dead centre when the handle is full down, and it will have a lot less power on the case.
H4831, I got my "misnomer" from reloading manuals and the die manufactures and its just a word. And when my 43 year old RCBS Rockchucker reaches cam over you do not see any daylight between the shell holder and the bottom of the die. And this cam over removes all the slop and wear I have in my old press.
Example below, Redding is using the word "cam over" when talking about reloading presses.
And my RCBS Rockchucker cams over and feels like "snapping the latch on a toolbox". And with all due respect H4831 my Rockchucker press is the only press I have ever used so a few other presses "may" not reach cam over, but mine does and it is not a "misnomer".Redding Tech Line & Tips (FAQs)
Some Frequently Asked Questions
Question: I have my Full Length Resizing Die/Body Die adjusted so that it is touching the Shellholder and I cannot push my shoulder back. Is there something wrong with my Sizing Die?
Answer: Probably not. In most instances, using Cam-Over will allow the reloader to push the shoulder back sufficiently.
To set a Full Length/Body Die up to Cam-Over:
1) Install the appropriate Shellholder into the Ram of your Press.
2) Raise the Ram so that it is in its uppermost position.
3) Screw the Full Length Resizing Die/Body Die down into the press until it firmly contacts the Shellholder.
4) Back the Ram away from the Die.
5) Screw the Die down FURTHER into your press an additional 1/8th to ¼ turn.
Note that you will feel the Ram/Shellholder contact the resizing Die before the stroke is completed. Completing the Ram Stroke will feel as though you are snapping the latch on a toolbox.
These directions apply only to standard Single Stage Presses. If your single stage press was not manufactured by Redding Reloading Equipment, please contact the manufacturer to see if using Cam-Over is appropriate for your particular Reloading Press.
http://www.redding-reloading.com/tech-line-a-tips-faqs/132-faqs1
And again H4831 no offense intended its just a word commonly used, it another forum I used the term "deck height" when talking about shell holders and the area the case rests on and another poster said he could not find this word in the SAAMI definitions and criticized my use of the word. So cam over its just a descriptive word used in reloading forums that is frequently used and misunderstood by many.
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