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Necking down 270 win to 25-06

My question isn't so much can it be done because I know it can. What I want to know is will I have to turn the necks before/after to achieve proper neck diameter? As always, any help is appreciated!

Thanks,
Mike
 
Most likely won't need to turn the necks if using a production/commercial chambered bbl. There is no knowing for sure, until the chamber neck is measured and the final dimensions of the loaded round are known.
 
I do this to make 25-06 Ackley I use 270 brass the only thing u will have to trim them to length after u size them down more than likely.
 
CanusLatransSnpr said:
It's a Shilen barrel but, doesn't have a designation for neck diameter so one would assume std. saami chamber?

Make a chamber cast or have one made then you'll know for sure.

Bill
 
Re size the .270 case then fire form it in the 25-06 WITHOUT USING A BULLET. Then measure the neck diameter of the fire formed case and add .001 ". This measurement should tell you the neck diameter in your 25-06 chamber. Then if you add the 257 caliber bullet diameter to two times the neck wall thickness of a .270 case plus a minimum of .0025" for clearance that will tell you what you NEED and you can compare this measurement to the fire-formed case neck outside diameter dimension.
 
I have taken 30-06 LC brass and first run it into a 270 RCBS trim die , followed by running the case into a 25-06 RCBS trim die and cut off the neck that was above the die. Run the well lubed 270 case into a RCBS 25-06 trim die . Its that simple. I never had a problem with the 06 cases resized to 25 cases becoming to thick of brass in the neck.
 
When I read this I get a lot of "it should work" and "Ive never had a problem". Well Ive had a problem, I sized a bunch of 270 win brass down in my 25-06 dies. Cut to length and loaded with a known good load in my Ruger 77 -25-06. The first 6 shots were great. The seventh produced much recoil, lots of smoke, a bolt I could hardly open , and a missing primer. Found the primer in the magazine. Decided to check the headstamp to see what it looked like, it was gone, I mean there was no writing left. If you do this measure all loaded rounds and compare against a factory round and cull any that are very much bigger in diameter.
 
I've done this quite a bit with 30-06 Lake City brass, and I have not had any problems with a Dan Dowling chambered Hart barrel. Call Shilen, but I highly doubt the chamber is tight neck.

For mine, I annealed, then lubed well and ran once through a Forster full length die. I adjusted the die to produce a very slight crush fit, and trimmed.

My fireform loads were varmint loads using Speer 87 TNTs over surplus IMR4895 I have. Nothing too crazy, just a good mid-range load to form brass and sight the rifle in and to make sure everything was fine.

MQ1
 
I would anneal the case necks after you neck down or before, it will help eliminate the cracking of the necks. I found that you may only get two or three reloads before necks start to crack. I have used 06' and 270 to make 6.5-06 and 25-06. Measure the neck on a fired case (un-sized) from your rifle and that will give you the neck dia, the actual chamber will be about .001 or .002 bigger.
 

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