6mm or 7mm TCU velocities?

[handirifle]

Looking for velocities from 22" barrels chambered in 6mm and or 7mm TCU.  For my needs they need to stay at SAAMI 223 length overall, for working in a semi auto.

Please give bullet weight and type if you remember, and anyothe load data.  Am wondering how this round will stack up to the 6.8 SPC.

[blpenn66502]

I thought I might be able to get you some data for the 7mm TCU, but the 2.260 OAL limitation immediately restricts bullet choices to less than 120 grains (at least with the Hornady offerings) and probably only 100 grain bullets might meet your requirements (don't have any on hand to verify). 

The 6mm TCU would likely be a much more viable option to meet your OAL requirements but the 6.8 SPC has an advantage in case capacity.

[handirifle]

True, it does.  I was looking into the viablilty of converting my Mini 14 Target model with the heavy 22" barrel to the 6mm TCU.  It would only require it to be bored out and a slight rechamber.

The option of 6.8 would require that AND bolt work.  I'm not sure anyone will do either at this point.

I thought of trading in my 223 and just buying a 6.8 but it would cost me another $347 to get a new one, and the 22" barrel on my Target would net with higher velocities than the factory 18.5" one.