6mm TCU

[bumtownbutch]

I have had a 6 TCU bolt action rifle built using a Snowy Mountain SA and a Krieger #17 contour 1-10" twist. I have been reloading and working up loads for it. Last Sunday, I shot a load of 29.4 grs. of H322 (case full) with a 55 gr. Sierra BlitzKing bullet @ 3624 fps average without any pressure signs.
I am asking for advise and guidance of those that have had experience with this cartridge for load data; am I near maximum? Are there better powders for the 6 TCU using the 55 gr. Sierra BKs?

 

[Randfal]

Sorry I don't have any data for you. I barreled up one with a 1:14 twist #17 barrel a few years ago but only managed to form fire a bunch of brass with 55gr bullets before it was put on the back burner and I moved on to the next winter project. I used Tac for my fire forming and used max Plus 1 grain over some published data for 6x45 loads for a few formed brass rounds and never saw any pressure signs. Also did the same with a few XBR8208 loads and never saw pressure with Lapua brass and CCI BR primers. I hope you get some replies. I would like to see what guys are getting out of there 6TCUs with rifle length barrels. All data is based on short TCU barrels etc. so it always looks sleepy when you first glance at data for it. I'm close to revisiting that project and get that rifle tuned back up.

 

[Randfal]

Forgot to ask, How long is your barrel?

 

[bumtownbutch]

It's 26" in length. I just received some reloading data from another reloader and plan to work up to his data for the 6 TCU; I'll advise results after shooting.

 

[GrocMax]

Accurate 2200 data for the 6x45 looks like it may be the go-to powder for velocity with the lighter bullets. Too bad I can't find any around.