One point that needs to be made (and forgive me if it was made and I missed it) is that if you use a shortened shell holder with another caliber die, you cannot set up the die to "cam over" because you will set the shoulder back too far and create an excessive headspace.
This is especially true with something like a 243Win because that same shell holder fits a wide variety of calibers.
Make sure you mark that shell holder!!!!

I loaded some ammo for this rifle with some bullets the seller gave me when I bought the rilfe. They are Sierra 85 grain bullets, original price marked with ink pen $4.15. Wonder what year that box of bullets was purchased.

Don't be too quick to assume that the cases aren't chambering because the die is too long. A quick, simple and free way to check is to colour the case with a sharpie and try chambering it. If the rub marks show that its the case diameter that is the problem then shortening the shellholder or die and pushing the shoulder back isn't doing you or your brass any favors. Oh sure, it may very well get them to chamber, because not surprisingly pushing a tapered case farther into a tapered die is going to make it smaller. Trouble is, it also increases the head space at the same time. Rimmed and belted cases get an exemption.

I've had many instances of cases fired in one rifle that wouldn't fit in another. Small base dies usually saved the cases. Sometimes you can get inventive. A .308 die with the expander assembly taken out works as a body die on a .243. If your .308 happens to be smaller than the .243 was it can solve the problem. I had a bunch of fairly fresh .257 Weatherby brass that wouldn't chamber in a new rifle. Running them through a .270 Weatherby die worked, because that die just happened to be a little snugger. I get a lot of use out of my small base .300 Win die since it will work on most of the standard length magnums. A small base 30-06 will massage a .270 a bit if you needed to.

Blacktailer, most would not set up any FL sizing die to cam over as a matter of course. As a reloader wanting to size cases to suit a particular chamber you would normally back off the die from cam over and adjust your die down until your cartridges are a snug fit in the chamber. Most factory ammo is a rather sloppy fit in most chambers,and as a reloader you can duplicate this if you wish by always setting your FL dies to cam hard over so your ammo has a good chance of fitting any chamber. Of course marking a modified shell holder is fine but that shell holder can still be used for any cartridge of that head size, just adjust FL dies accordingly.

Dogleg if a case won't chamber or is tight to chamber it means the case head is hard up against the bolt face because that is the only thing pushing the case into the chamber and with a tight case it can not go anymore. Modifying a shell holder to make the cases fit the chamber is not going to make a difference to headspace as you only sand or grind down the shell holder enough so the case is a snug fit in the chamber. Whether it is headspacing off the shoulder or the body of the case if it is a snug fit either way it will be hard up against the bolt face i.e. correctly headspaced.
Once fired in that chamber it will then be fireformed to fit properly. If the shoulder has been pushed back it will fireform forward just as many do when making wildcat cases, often using the bullet jammed in the rifling to hold the case back against the bolt face for firing.

Redding told me similar things one time. The die was the issue

I have several rifles that are .473 rims. My 250 savage I built I set the barrel to headspace with a factory cartridge. Didn't want to wait for headspace gauges. Anyway a lot of my reloads chambered a bit firmly.
Buying new brass was the same, some a bit firm. I modified a shell holder as described earlier.
I keep this particular shell holder with that set of dies.
I have other shell holders for the other cartridges that have the same head size.
A few bucks for a shell holder to modify and keep with those dies isn't much of a problem.
If you have more than one .243 color your modified shell holder and get another for the other rifles.
Still not much of an issue.
Shell holders are not expensive.
If you buy Lee die sets they come with one so they are essentially free.
Leo

I've had dies reworked by both Redding and RCBS. In the end it was a essentially a custom die for nothing. Sort of like winning the lottery.

i have had the expender button pull the shoulder foreward on 243 cases before. take the expander-decap assembly out of the die and size a case and see if it will chamber in your rifle.

My experience with a 243 Lyman, RCBS, Forster sizing dies. If I put a lot of lube on the case the I had no difficulty when chambering. When I switched to using a Lyman 'M' die used to expanding the neck and putting a slight flare on the case mouth, I never had a problem. The expander ball as it pulled out pulled out pulled to neck forward.

Jim

Redding sells undersize shell holders and a graphite lube that you dip the necks in to prevent pulling the neck.

I wish I would have found this when I got a new barrel done in 6.5x55. I had a bunch of once fired Lapua brass I got rid of and bought all new brass. This was very informative.

Update on some remington 6.5x55 brass already fired in another rifle. I took .006 off the shell holder thickness and most of them worked like a charm. Some was still a little tight. I wish I hadn't sold the Lapua brass now.

If you cant get a case to fit by snuging the die adjustment up to the shell holder as much as possible then I would wonder if a go gauge will even close in the chamber. If not, there is your problem. I have a 358 BLR that is hell for tight chambered, but getting as much "squish" as I possibly can from the die will make it fit. RCBS knows how to make dies, your dies may not be the issue at all.

Note; this grinding of the shell holder is ALTERING HEADSPACE AND POTENTIALLY DANGEROUS! Most of those who do it already know that, this disclaimer is for those who may not. If you are unsure, dont do it!! The alternative "fix" is to take your rifle to a gunsmith and have your chamber set properly.

quote:

Originally posted by Blacktailer:

Make sure you mark that shell holder!!!!

And make sure no one EVER "inherits" it who doesnt know the whole story.