Gunsmithing Help with 260 Build

[ChadJamesR]

I'm building a new rifle and wanted to get some input before I send the parts to the gunsmith. The rifle will use a TAC30 action, BO DBM, and T4A Stock. The questions I have are the following:

The chamber will be a match PTG reamer. I have read that both a .06" and a .1" freebore is idea for shooting the 140gr bullets. As I plan to shoot 123 to 140gr bullets, which do you recommend for the freebore and why (ideal cartridge OAL would be 2.8")

I'm looking Bartlein barrels. I can get a 8.5 twist 5R Bartlein MTU contour barrel in a few weeks from a shop, or would it be worth the 8 month wait to get an 8 twist barrel directly from Bartlein? I plan to have the barrel finish at 26".

These are the only two specs I'm undecided on. Any information you can give would be helpful.

If anyone has built a 260 before and can give me ideas of what to do and not do, that would be great as well.

Thanks,

Chad

 

[Snafu12]

Re: Help with 260 Build

Go 1 in 8
130 Bergers are doing well for me
I have a 5R #10 HV

 

[rksimple]

Re: Help with 260 Build

Most guys around here are runnning 8.5 twists. They do very well with the 139s and 142s. I have an 8 twist as thats what was in stock when I wanted one, no other reason.

My chamber was done with a PTG 260 rem match reamer (don't remember the freebore) and I load 142 SMKs to 2.835. When new, they were sitting about .010 off the lands IIRC. No problems.

 

[ChadTRG42]

Re: Help with 260 Build

I built my 260 with very similar specs as yours- Surgeon action, Manners T4, BO BDM. I went with a 4 groove Bartlein 1:8.5" twist, and my next 2 barrels I just bought are 8.5" twist. I run the 140 VLD's.

On your free bore, I had my smith cut the lands seperate from the chamber. I provided him dummy rounds to cut the lands to the length I wanted. It still ended up a little longer than I liked, but it works fine. I would cut it to touch the lands on your dummy round at 2.800" with which ever bullet you plan to run. Maybe 2.810". You will need to chase the lands about .030"-.040" after ~1000 rounds. I'm there now, and at max mag length of 2.860" in my BO BDM.

 

[ChadJamesR]

Re: Help with 260 Build

Has anyone had any bad experiences with a .260 build and a 8.5 twist barrel?