PDA

View Full Version : 6.5 Tcu ?


tommag
03-03-2008, 03:10 AM
I have been thinking about a 6.5 tcu bbl for a contender. I wonder if anyone has any experience with this in cast? I was hoping the case capacity would be ideal for cast, but when I do the Greenhill formula, I come up with an 8 twist for the 160 NEI bore-rider. I was hoping to push the long 6.5's a bit faster than I can in the Swedes with a slower twist, but with the published velocities for the tcu, maybe this isn't the best choice.

Could one of you with the Lyman 140 gr Loverin mold tell me what the length of that boolit is? Perhaps that would be the best mold for a 6.5 TCU. I wish I had gotten in on the 6.5 Kurz group-buy.
jhalcott
03-03-2008, 11:50 AM
I know the formulae say it ain't so BUT I have used a 168 grain cast in my 7tc/u in 14" and 21" barrels. I have used it to cull deer causing problems in populated areas with GREAT success. I feel that it is BETTER to try some thing than rely on hear say about it. You CAN order custom barrels with special twists.
Glen
03-03-2008, 12:39 PM
The 6.5 TCU does just fine with cast bullets.....under the right conditions. The fast twist is somewhat of a limitation, but if one throttles back a little bit, cast bullets shoot just fine. So far, I have had NO luck shooting PB bullets in the 6.5 TCU, but GC bullets seem to do just fine up to about 1800 fps. TC tends to cut oversized throats, so for best accuracy you will probably need to size your bullets .266" or .267". Every time I've tried .264" cast bullets in the 6.5 TCU, I have been treated to abysmal groups. 4895 is an excellent powder for cast bullet loads in the 6.5 TCU -- for example, see:

http://www.lasc.us/FryxellCastHP-Contender.htm
tommag
03-03-2008, 06:59 PM
Thanks for the responses. I was thinking about an 18-20" bbl with a little slower twist than my Swede. I have an NEI 125 gr mold that would work (at least on paper).

I like my m-96 and thought the 6.5 tcu would make for a handier woods rifle. Glen, from that article, it sounds like I should go with a faster twist and just consider it a match for the swede, performance-wise. Are you the same Glen as the author?