Neck Sizing 243 brass to 7mm-08

[roc1]

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I have sized 308 brass to my 7mm-08 with no problems. I also have and abundance of 243 brass and was wondering what problems if any would be caused by necking 243 back to 7-08? This would save buying 7-08 cases. Do you have turn necks or anything else?
Thanks
roc1

 

[lost river rat]

Not well

Doesn't work well. Necks collapse and are very thin when done. Prone to cracking and reduces neck tension. Practice loads only.

Use a .25 or .26 intermediate to increase yield.

 

[GooseGestapo]

I've used my Lee FLD and had no problems.
Some of the most accurate brass I've used is Remington and PMC .243 necked up to 7mm08. (Thicker than Federal or Winchester)

Necks will be a tad thinner than necking down .308wcf. Often, when necking down .308 I need to neck turn the brass as my Rem M7 has a very tight neck and short chamber/throat. But, the barrel IS FAST ! Like 2,900fps from 20" bbl with factory equivalent loads.

I suppose it depends on which type dies you're using. If using an RCBS or Lyman die, it could damage the neck. The Lee's have a taper ground on the end of the decapping pin-rod and this initiates expansion of the brass.

I've also had good luck necking down .308 to 7mm08. No need to resize in .308 die either, before necking down OFB.

 

[50calshooter]

anneal the brass buy a 650 deg crayon the brass will last along time. Better if you neck to 264 than 7 mm

 

[interlock]

i regularly go up from .243 win and down from .308, both work well

 

[lost river rat]

Correct

A tapered expander is essential. RCBS expanders tend to ruin a lot of case by compressing the neck. Annealing really helps. The thin necks don't meet my needs.

Necking down from 308 and neck turning to just concentric makes for very accurate loads as the neck is usually near normal thickness and concentric. Works well in a std chamber. Custom chambers may need special care to ensure at least 0.003" under chamber dimension for correct release. My 7-08 is near minimum SAAMI specs (Savage) and takes necked down/turned to concentric rounds with ample bullet release. The necks are plenty thick for hunting ammunition (all I use)

Try 10 and see how it works for you.