TCR Monobloc

[dragonrider]

So I have gotten this far in the contruction of a new monobloc for my TCR-87, will be sticking a .243 cal barrel in it. Finaly got the lock fitting today. One of those parts that you need to sneek up on .001" at a time or you will miss the point at which the lockup occurs and end up with begining to get sloppy. A few pics of progress so far. click the pics to enlarge.
Start by milling the block shape.
http://img.photobucket.com/albums/0603/PaulGauthier/TCR%20Monobloc/th_TCRMONOBLOC019.jpg (http://smg.photobucket.com/albums/0603/PaulGauthier/TCR%20Monobloc/?action=view&current=TCRMONOBLOC019.jpg)

Then start with the pivot hole
http://img.photobucket.com/albums/0603/PaulGauthier/TCR%20Monobloc/th_TCRMONOBLOC020.jpg (http://smg.photobucket.com/albums/0603/PaulGauthier/TCR%20Monobloc/?action=view&current=TCRMONOBLOC020.jpg)

then the barrel mounting hole next time I'll have a reamer for that, boring takes way to long
http://img.photobucket.com/albums/0603/PaulGauthier/TCR%20Monobloc/th_TCRMONOBLOC010.jpg (http://smg.photobucket.com/albums/0603/PaulGauthier/TCR%20Monobloc/?action=view&current=TCRMONOBLOC010.jpg)

Here I am shaping the slot for the extractor,
http://img.photobucket.com/albums/0603/PaulGauthier/TCR%20Monobloc/th_TCRMONOBLOC033.jpg (http://smg.photobucket.com/albums/0603/PaulGauthier/TCR%20Monobloc/?action=view&current=TCRMONOBLOC033.jpg)

Here I have the mounting and locking work done. Although it is not yet fit.
http://img.photobucket.com/albums/0603/PaulGauthier/TCR%20Monobloc/th_CopyofIMG_8010.jpg (http://smg.photobucket.com/albums/0603/PaulGauthier/TCR%20Monobloc/?action=view&current=CopyofIMG_8010.jpg)

Now I get to see if it fits
http://img.photobucket.com/albums/0603/PaulGauthier/TCR%20Monobloc/th_TCRMONOBLOC010.jpg (http://smg.photobucket.com/albums/0603/PaulGauthier/TCR%20Monobloc/?action=view&current=TCRMONOBLOC010.jpg)

Presto it fits.
http://img.photobucket.com/albums/0603/PaulGauthier/TCR%20Monobloc/th_IMG_8021.jpg (http://smg.photobucket.com/albums/0603/PaulGauthier/TCR%20Monobloc/?action=view&current=IMG_8021.jpg)

this shot shows that the block is still oversize around the barrel mount area.
http://img.photobucket.com/albums/0603/PaulGauthier/TCR%20Monobloc/th_IMG_8023.jpg (http://smg.photobucket.com/albums/0603/PaulGauthier/TCR%20Monobloc/?action=view&current=IMG_8023.jpg)

Next thing is to stick the barrrel in it and pin it in place. Then machine the remaining material to blend with the frame.

[dubber123]

Nice looking work! I just bought an old break action for a small game gun project, and need to make a locking lug/pivot block. Your pics came at a good time!

[Frank46]

Dragonrider, why not thread the mono block and just screw in the bbl? Just curious.
Beautiful work by the way. Precision shooting had an article by Norman Johnson some years back. Think he took an origional mono block and either threaded it or bored it out and set the barrel in with set screws. Was using rem varmint take off barrels. Frank

[dragonrider]

Sorry I haven't answered your ? until now Frank, just saw it.
I thought about threading but there is a couple of things to consider, the size of the thread,
the wall thickness of the monobloc, .080" and the length of thread at 2.5"+. I don't think I could tighten it sufficiently with breaking the bloc. When I put them together I will heat the bloc to 400 degrees and freeze the barrel overnight, if I get it right and they slide together leaving just a few thou to face off and this will leave the chamber short and I will hand ream to finish it. I hope to get to that this week.