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down sizing 308 to 708, issues?

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22 September 2015, 15:16
WhelanLad
down sizing 308 to 708, issues?
hi guys whats the issues with resizing down from 308 to 708 with brass?

I will be hoping to do this for a kimber Montana, which I have heard can have tight chambers

thanks in advance

wl
22 September 2015, 16:24
p dog shooter
A lot depends on the brass and chamber.

My son brought his wife one and 7-08 was not to be found.

So what the heck I said buy the dies and I'll make some. I have lots of 308 and 243 brass

I found that 243 federal brass worked out the best of the ones I tried. The other had chambering problems.

The federal 243 was one pass load and shoot.

One needs to resize it and check the dimensions and try chambering it.

As I did you might find one type of brass is better in that rifle than another.
22 September 2015, 16:25
9.3 X 75R
Only things that come to mind is neck thickness and checking case length after sizing. If such be the case inside or outside neck turning should fix the thickness and trimming will take care of case length.


DRSS: E. M. Reilley 500 BPE
E. Goldmann in Erfurt, 11.15 X 60R

Those who fail to study history are condemned to repeat it
22 September 2015, 17:17
WhelanLad
yeah ok, I hope to get awy with out the neck turning!

is it just one go thru the Die for sizing the 30 to 7?

I do have some old 243 brass here but I don't think its in that good of condition. may pull the bullets if I have too once I figure out if il be ok with the 308 brass
22 September 2015, 19:01
Fjold
Going down from 308 to 284 isn't bad, I did it a number of times with no need to neck ream. The die squeezes it down and the internal neck diameter is too small but when the expanding plug is pulled back through, it restores the diameter. A little extra neck thickness usually helps in a factory chambered rifle.

Necking down to 260 to 243 is where reaming is required.


Frank



"I don't know what there is about buffalo that frightens me so.....He looks like he hates you personally. He looks like you owe him money."
- Robert Ruark, Horn of the Hunter, 1953

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22 September 2015, 20:08
dpcd
Usually no prob with commercial brass; military brass might have thicker necks; all depends on your chamber.
A friend makes 260s out of 308s with no issues too.
22 September 2015, 20:55
Blacktailer
quote:
Originally posted by dpcd:
Usually no prob with commercial brass; military brass might have thicker necks; all depends on your chamber.
A friend makes 260s out of 308s with no issues too.

Yeah, I've resized a number of milsurp -06 to 270 without problems. You should be OK as far as the necks go with just lube and one pass but of course check everything as you go.


Have gun- Will travel
The value of a trophy is computed directly in terms of personal investment in its acquisition. Robert Ruark
23 September 2015, 03:53
wasbeeman
It's pretty simple. Put together on round, resizing a .308 case, charging with powder, and seating a bullet.
Fire that one round and if a .264 bullet will slip into the neck of the fired case, you do not have a neck problem and don't need to neck turn. Do that with each fired round and when the bullet will no longer slip into the neck, you'll need to neck turn.


Aim for the exit hole
23 September 2015, 04:04
The Dane
quote:
Originally posted by wasbeeman:
It's pretty simple. Put together on round, resizing a .308 case, charging with powder, and seating a bullet.
Fire that one round and if a .264 bullet will slip into the neck of the fired case, you do not have a neck problem and don't need to neck turn. Do that with each fired round and when the bullet will no longer slip into the neck, you'll need to neck turn.


You what?
23 September 2015, 06:40
dpcd
He means .284.
23 September 2015, 08:57
bigrdp51
quote:
Originally posted by WhelanLad:
hi guys whats the issues with resizing down from 308 to 708 with brass?

I will be hoping to do this for a kimber Montana, which I have heard can have tight chambers

thanks in advance

wl


Measure the fired neck diameter of one of your 7mm-08 case necks. And then measure the neck diameter a loaded round using the .308 brass. The new loaded rounds neck diameter should be at least .005 smaller than a fired case and thus giving you .0025 neck clearance. This is the minimum for a tight neck chamber, and a factory chamber would be much more.
23 September 2015, 15:30
WhelanLad
hmmm rightio.

I actually don't have any 708 factory ammo LOL

I will lend one off my cousin an send through it for measuring purpose.
24 September 2015, 01:23
wasbeeman
quote:
Originally posted by dpcd:
He means .284.


Yes, thank you. Smiler


Aim for the exit hole