sizing 308 to 7mm-08 - annealing, does it make a difference in force when sizing?

RonR

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Inherited here is 70 plus 308 imperial brass. It looks to be once fired. Aim is to size down to 7mm-08.

Read the threads here using those search terms. Doesn't seem to be a consensus whether it's worth the effort to anneal to achieve the end result.

I haven't done this before, and from those who have experience...would annealing make much difference with respect to force required to size?

Regards
Ronr
 
I reform a lot of brass and allows found annealing of benefit. Annealing softens the brass and lets it flow better which stops the brass from rippling and folding. Making a case that is smooth and fits your chamber is what's important. The imperial brass would not be the best choice for this. Towards the end imperial really sucked with quality issues. I have older imperial brass which has lasted past 20 reloads. If that's all the brass you have I would try a few and see what happens. I always anneal cases before I change their shape. I place them in the sink with water just under half way up and heat with a torch until they just start to turn red.
 
I have sized up 7mm08 & 243 to 308 but not down.
Yes it makes it easier but was not bad without it.
Basic full length sizing of 7.62x51 surplus brass was much harder to do.
 
I reform a lot of brass and allows found annealing of benefit. Annealing softens the brass and lets it flow better which stops the brass from rippling and folding. Making a case that is smooth and fits your chamber is what's important. The imperial brass would not be the best choice for this. Towards the end imperial really sucked with quality issues. I have older imperial brass which has lasted past 20 reloads. If that's all the brass you have I would try a few and see what happens. I always anneal cases before I change their shape. I place them in the sink with water just under half way up and heat with a torch until they just start to turn red.

This is the best advise I've read on here so far....
 
if the brass turns red it is too hot.

I have done a bunch of brass over the years .... hold brass in my bare fingers, rotating back and forth .. when it is to hot to hold drop in a bucket of water
very low heat(torch) brass pointing up .. combination of fingers and a count
 
If it's only about sizing effort; try Imperial Bio Green sizing lube. I don't know what's in it but I've never seen anything that comes
close for ease of sizing.

Necking down by itself takes very little effort though. Most of the effort will be sizing the body.
 
Thanks for the responses.

I should have been clearer in the original post, I've never resized from 308 to 7-08 before.

Annealing won't be a problem.

Regards
Ronr
 
If it's only about sizing effort; try Imperial Bio Green sizing lube. I don't know what's in it but I've never seen anything that comes
close for ease of sizing.

Necking down by itself takes very little effort though. Most of the effort will be sizing the body.

Thanks for the insight regarding where most of the effort is used. Imperial sizing wax has worked well for me.

Regards Dogleg.

Ron
 
I have re-sized 308 to 7-08. The feel and effort was not much different than an ordinary FL size. Just use enough lube.

All my 243 was made from 308 - a bigger step down, and I did not anneal those, ether. Lasted many re-loads, too.
 
Imperial sizing wax and Imperial Bio Green are in totally different worlds. Trust me on that one.

Thanks for picking up on the fact that I wasn't getting it. Lube pad application with the Bio Green? Ganderite uses the Lee lube and one day I will try that out as well.

And thanks Dogleg!


I have re-sized 308 to 7-08. The feel and effort was not much different than an ordinary FL size. Just use enough lube.

All my 243 was made from 308 - a bigger step down, and I did not anneal those, ether. Lasted many re-loads, too.

Bingo. That's what I was looking for.

Thanks Ganderite

Regards
Ron
 
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I just did a batch of 200 lake city 762 x 51 brass necked down to 7-08. Lubed them with imperial wax, inside neck too. As happens occasionally I had to turn the necks as they were to thick to properly release the 284 bullet.
 
I just did a batch of 200 lake city 762 x 51 brass necked down to 7-08. Lubed them with imperial wax, inside neck too. As happens occasionally I had to turn the necks as they were to thick to properly release the 284 bullet.

I will measure and see how thick/consistent the necks are after sizing. Here neck thickness is turned to .012 or .0125...something that I got into to solve a neck tension issue. My rifles don't need that thickness, but I am here now. If I started reloading with better brass I don't think I would have gone down that road.

Wax on the inside of the neck...good to know. I'll see what the results are like using a dry film lubricant. The instructions with the Forster die recommend dry film but truthfully I am new to the full length sizing game and don't have any experience to know which would work better for myself. Fire, neck size with collet die, repeat has been the m.o. for myself up to this point.

If this works out I'll entertain exactly what you have just completed. Lake City or other suitable mil spec. The swaging is a pita and I've often wondered if the touch time/labour to convert that stuff is worth it when compared to Lapua or other reputable make. I am certainly not a brass snob but my time and everyone else's is worth something. In my mind the increased touch labour when amortized over the life of the brass should be worth it. No argument provoked with the smart reloader's that load and shoot.;) I am seeing the merit in that as time goes on.

Regards whiskey and thanks for posting that. I was wondering about Lake City conversion.

Ron
 
Military brass may have a thicker neck, so when necking down, it might be better to stick with commercial brass.

Here is how I lube brass when sizing more than 20 cases. This method gets a little lube into the neck, so cases don't get stretched as much.

 
Military brass may have a thicker neck, so when necking down, it might be better to stick with commercial brass.

Here is how I lube brass when sizing more than 20 cases. This method gets a little lube into the neck, so cases don't get stretched as much.


Noted on all points. Thanks for posting Ganderite. Lubing en mass like this is appealing and if that's how you do it, it's got to work...even for a newbie full length sizer like me. :redface: I've got a tube of that stuff on hand and I am staring at a container that will work just fine at the moment.


Best Regards :cheers:
Ron


P.S. I wonder if the stuff Dogleg is using or any other oil would work in the same manner of application. The viscosity of the lee lube is higher than a liquid I know, maybe that's the reason why oil/liquid lubricant in a jug wouldn't work.
 
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