I just picked up a new but "blem" 7" barrel for my SW 41. The barrel is D&T for a mount but only had two filler screws installed in the front/ blind holes. The rear two (through) holes won't accept either those filler screws or screws from the Weaver mount I'm trying to install. ( The screws won't even start). I'm thinking I may have to chase those holes with a tap to proceed. Can any one tell me what size screw is used in those locations? Anyone else have this issue? A search turned up nothing.

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Dave

I bought one of those same barrels and have the same issues. I had to chase those two holes with a tap. 6-48 is the correct size. I wonder if the barrel was blued after tapping the holes and filling them just a little bit?

Interesting that these barrels were sold as “blems” but the package says “demo”. I can’t find a blemish anywhere. Will shoot it tomorrow to see how it performs.

Scope bases on rifles generally use #6-48 or #8-40 threads. I’m not familiar with the D&T Model 41 barrels but would “imagine” they would follow that convention. Do the threads appear to be damaged? Possibly just dirty and need cleaned? A strong flashlight and magnifying glass might give you some clues. Are the screws you are trying to use in good condition?

Thanks much! Mine came unwrapped and unmarked. It also didn't have a mark on it. It was smothered in some sort of old brown cosmoline/rust looking finish that needed multiple scrubbings to remove though. It's a nice barrel when it cleans up! I'll hunt up a fresh 6-48 tap today.

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Dave

You’ll probably have to buy the tap on-line. I’ve never seen that size in a local hardware store. It is the standard size for most sight mounts.

The final wrap on mine was a plastic ziplock bag with a S&W label marked “FACTORY DEMO NO BOX NO SIGHT” and an original price of $299.99.

Yeah, that brown coating is a real pain!

Had my new barrel to the range yesterday. It’s a tack-driver. Hope yours is as good!

I bought the tap off Amazon and ran it through the barrel. As expected it was only the two through holes that required it. Mounted my picatinny rail and put on a red dot. I filled in the rear sight dovetail with a 2mm piece of dense (black) foam while I was at it. It looks good. I've only done one range trip but so far, I'm liking it. Lets just say that the barrel is at least up to par with the 5.5" that came on the gun. At this point, it's only the old guy behind the trigger that holds this setup back. I'll likely put a scope on it and try it at a rimfire silhouette match soon.

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Dave