I am rebarreling a Tantal for a customer using a Bulgarian barrel reprofiled to suit. I made a rookie mistake and assumed the barrels would be as specced on the prints, where both barrels are the same diameter at the trunnion end.

Not the case as the Bulgarian barrel is about .003" smaller than the print call-out. So rather than a press fit, its more of a tight sliding fit into the Tantal trunnion.

I find this out after the barrel has been re-profiled and parkerized.  Not very smart, I'm afraid.

My question is this: Can i chemically retain the barrel (red locktite) at the proper headspacing to then drill the barrel pin? Or a light knurl on just the portion hidden by the trunnion, then the locktite?

So my gut tells me this receiver should get a Bulgarian trunnion installed but that will run the cost up beyond the value of the firearm for the customer as there will be a refinish involved as well as the cost for the trunnion and possibly the bolt.


Thoughts?

Turn down and sleeve?  The pin hole could be drilled oversized and a custom pin made to ensure enough of the meat of the barrel got grabbed.

Knurl the barrel.

^^^^this! And a dab of green Loctite.

Knurl it is. Some further research on other boards has shown this "stacking" of tolerances has been successfully addressed before.

I used a fine knurl and it took very little to displace enough material to make a proper press fit.

Thanks everyone for adding your thoughts.

Another tip is to slip the barrel into the trunnion until the rear sight base is flush with the trunnion ears (where it would be installed normally) and mark the portion of the barrel that's covered by the trunnion with a scribe. Then remove it and knurl only the part that is covered. That way when you install it you won't be able to tell that it's knurled and will look factory.

ETA: Never mind, I see that you already mentioned it.