270wsm and Barnes TTSX powder question

[ramrod79]

I use the 110GR Barnes TTSX out of my 270 WSM using IMR 4350 loading to the Barnes Manual, and it was a tack driver . I also shot 130TTSX using 4350 and same seating depth ,and was handed the same results this was out of my factory Rem 700 with some light bedding work ,and a trigger job .

 

[Jesse09]

Ramrod79, I have the Barnes manual; it doesn't specifically list the TTSX, but the Barnes tech advised me to use the data for the TSX BT, and I'm doing that. One thing that confused me was the listing in the manual of C.O.A.L. of 2.745". I asked the tech what it referred to, and he said it was simply the cartridge overall length of the cartridges they shot to establish the loading parameters listed in the manual.

Today I loaded my next round of seating depths to test; among them is one loaded to the C.O.A.L. of 2.745". This results in a bullet that is .220" off the lands in my rifle. That's a huge gap and one I never would ordinarily try. Adding to the uncertainty is the fact that I am loading the TTSX, whereas the data was obtained with the TSX BT; I'd imagine the ogives are not identical.

BTW, do you remember what your seating depths were? Close to the lands or big gaps?

Jesse

 

[Jesse09]

A lot has happened since I started this thread. I had originally sought input in developing a load for my new Tikka T3 270wsm. After settling on the suggested Barnes 110gn TTSX and IMR 4350, I went through the usual routine of starting at a safe powder level and adjusting seating depth for the best results, then increasing the charge weight, etc.

My last entry in my notebook says it all, "I give up!" That day, I had recorded groups of .3", 1.+" and almost 2"; all with the same load and under ideal conditions. My logbook notes 586 shots on the barrel; that should not have signaled a shot-out barrel, I thought. (I had expected the barrel to last between 800-1000 shots, especially because I had limited muzzle velocities to around 3300 fps for most of my previous shots; and had always cooled the barrel between shots.)

On a hunch, though, and because I couldn't think of anything else to check I had a custom gun maker scope the barrel. He confirmed that it was shot out, though he said he couldn't believe how bad it was after that number of total shots.

Here's where I am, now:

The gun maker, Jered Joplin, is building a new rifle for me. I brought him a new Tikka T3 in 270 wsm and he will use that new action, a Broughton #4 contour barrel and the McMillan A3-5 adjustable stock for the Tikka T3. The barrel he takes from the new Tikka action will go on the old Tikka action. This will give me a second "new" rifle to sell.

In case anyone wonders why I didn't just install the Broughton barrel on the old Tikka action, here's what happened, there. I had previously tig-welded the recoil lug to that action in what Jered thought was a questionable thing to do. He was concerned that, unless I had the lug perfectly positioned, recoil would be torquing the action every time I pulled the trigger. He didn't insist that would happen, but he planted the seed.

Anyway, I'm pretty excited about the project; he's promised to have the rifle completed in 90 days, depending on Broughton's delivery. I think I'm going to have him Cerakote the barrel and action to match the finish on the scope I'm planning to buy for it: The Vortex Gen II.