I picked up some of my mates 308 cases that he leaves on the ground at the range the other week.
For some reason I put them in the tumbler with my 7mm rem mag shells, and when I pulled them out, curiosity got the better of me and I decided to see how they would go being necked down to 260 Rem. A bit of case lube and bugger me. A 260 Rem case. Is that it? Is it really that easy?
Lapua 260 Rem brass goes for $140/100, but 308 brass is only $80/100. Might get busy on the press and neck down some Lapua brass, because the Remington stuff is a bit to much like their barrels, the hole isn't in the middle, if you know what I mean.
Have a good 1, and remember. It's only 7 days til Missedathon!
You will find that they end up about 20-25 thou too short. It is up to you to decide if that is a problem. I run necked down 308 cases in my 7-08 without any issues.
I found when necking down that the thickening of the neck seems to concentrate on one side. You could see when giving them a skim turn brass only came off from one side. That made my mind up to always turn the necks after necking down brass
Yeah its that easy, I ran some ADI 308 brass through my 7mm08 fl sizer the other day and they came out the same as the others have said, will be getting a primer pocket uniformer to do the pockets and will get around to skimming the neck, they are a couple of tads thicker in the neck than my factory brass, and just a bit shorter. As 308 they were 2.005 long but after resizing they were 2.012, they will be good cases when Ive finished I reckon. The ADI brass seems to me to be very good stuff, very even length wise and seeing as I now have around 500 of them, think they will be used as my "Don't really care if they drop on the ground and get lost brass".
I run 308 palma cases for my 260 improved f class gun. Neck to 7-08, then 260, turn to give 1-2 thou tension with a 292 bushing, load and shoot with 140 hybrids, CCI450's and 2209. The first chambering in this maddco has been a bit of an experiment but I think Ive just nailed it and will rechamber shortly as Im just about out of throat.
I like 2209 but a mates 243AI with RL19 is very very good at 900m three or four bullet holes high with horizontal spread to suit the winds. My 260 (improved) is very similar but im doing a little more work tomorrow to tighten it up vertically a bit more. Im using berger 140gr hybrids.
I have been pondering this for a little while now, and even gone to the point of thinking about what necking down PALMA brass would be like.
Some people have said neck down gives more up neck turn uniformly, other says stretching out smaller cases gives uniformity inside the neck..
I am about the hit the shed tonight and check the necks on my Remington .260 cases, some of Camels small batch ADI and should have my VERY LONG AWAITED Lapua brass by wed or Thursday so i can order my bushes for my Foster die.
I'm just running a hunting chamber at the moment but wanted to start with the proper gear, has anyone using bush dies needed anything larger then 0.292?
The main reason I run 292 bushing is so a loaded round can be at 293 or 294 depending on what seems to work better and I can maintain 4 thou or more clearance in the chamber. I could turn further and run a smaller bushing if I wanted to but turning really isnt all that fun. Some folks in my game (f class) have found that tight neck chambers without decent clearance can sometimes cause a bit of vertical. So I now try to run 4 thou on my 6 and 6.5mm and 5 thou on my 7mm.
For your chamber if you want to know the neck diameter just measure your fired brass necks and add half a thou for springback. Then you know if you want to try necked down 308 cases you will need to have a loaded round diameter 4-5 thou smaller than that of a fired case.
The main reason I run 292 bushing is so a loaded round can be at 293 or 294 depending on what seems to work better and I can maintain 4 thou or more clearance in the chamber. I could turn further and run a smaller bushing if I wanted to but turning really isnt all that fun. Some folks in my game (f class) have found that tight neck chambers without decent clearance can sometimes cause a bit of vertical. So I now try to run 4 thou on my 6 and 6.5mm and 5 thou on my 7mm.
For your chamber if you want to know the neck diameter just measure your fired brass necks and add half a thou for springback. Then you know if you want to try necked down 308 cases you will need to have a loaded round diameter 4-5 thou smaller than that of a fired case.
I am running a Tikka T3.
It's shown some great results whilst i have been waiting for my Lapua brass and dies to turn up from the bloke i bought the rifle from
Home made seating die for the necked out 243 cases
6 shots with varying OAL due to my seat die... just picked the load as i got impatient waiting to run the rifle
So i guess the suggestion is then even out the necks on the brass, fire them and then measure fired case. Or technically i don't even need to clean the necks up to get close enough to the meausure to base my ordering off then rifle?