My 2nd Krag

[ssgross]

Fitting that sight base was kind a lot like golf, no matter how good you think you're doing, you are only ever one stroke away from ruining an otherwise perfect score or day.

[ssgross]

next question...the rear sight screws. ssfirearms sells repro 8-30 screws that fit perfect (my first krag with original barrel). criterion are tapped for 8-32 I think. I'm thinking I will get the $30 8-30 china bottoming tap and chase the threads, rather than wrench the new screws down in and possibly damage the barrel?

[browningautorifle]

next question

Ask Butlersrangers...or maybe Jon Norstog. Don't force fit.

[ssgross]

I've read some just force fit, but just to barely tight, and others suggested chasing the threads with the correct (sort of hard to find) tap. I don't plan on doing anything with it just yet - I have plenty of time for our friends to chime in. Thanks.

[butlersrangers]

I have not 'tinkered' with a Criterion barrel, yet.

The rear sight model, that you are going to use, might dictate your best approach.

Some of the Krag sight screws would be easier to replicate, (from 8x32 screws), than others.

I thought it kind of shabby that Criterion did not use an 8x30 thread, on their rear-sight holes, or make replica screws, with their 8x32 thread.

IMHO - They left the customer in a bind.

[ssgross]

The rear sight model, that you are going to use, might dictate your best approach.

I have an m1901 sight, and of course that elusive 8-32 screw with the long head for this sight has been searched for across the internet by many in many forums.

Several reported tightening down the originals (or ssfirearms.com accurate repros 8-30) without torquing on them (wow, auto spell check tried to turn that into twerking. very dangerous). Others mentioned chasing the threads with an 8-30 bottom tap - if you can find one. I did 2 places I think that sold them for ~$30 (have to look it up again). I didn't see any posts from anyone who actually reported doing this. Will chasing with 8-30 leave enough material on the barrel threads to work?

I was thinking maybe a combination? maybe I buy 2 sets of repro screws, the first sacrificial? Turning them in should push the top few threads in the barrel down to create the extra space, giving more material for the 8-30 tap towards the bottom?

[ssgross]

read this with my lunch today
https://www.theoutdoorstrader.com/th...-steel.647211/
big boost of confidence made my day.

[browningautorifle]

read this with my lunch today

Lots of good stuff in there, like paper polish instead of a wheel. Nothing worse than stretching screw holes or melting roll markings. Unless it's sanding the woodwork to below the lines of the metal it meets... I'm keeping that whole thing for future reference. I too have a couple Marlins to do.

[ssgross]

front sight is on. heated the bottom of the sight until the solder would melt when touched...test often so as not to heat more than necessary. Then I soaked a small ball of steel wool with flux and scrubbed the underside, holding the steel wool with tweezers. Then applied the heat until the solder flowed once more, puddled some of it on and wiped with the steel wool to get a nice even coat.

Let it cool while I enjoyed my morning coffee with the Mrs. on the porch. It finally cooled down here after the rain, and it was a beautiful 72 deg, low humidity, and gentle breeze, but the week long of humid 100 deg. ruined my hydrangeas, no matter how much I watered them through the week.

Once it was cool, I cleaned up the solder off the side edges, and a bit that dripped down the side with the flux. fine brass wire wheel on the Dremel does nicely, followed by sandpaper backed by a file.

Next, I degreased the front of the barrel, scrubbing up under the dovetail with acetone really well. I leveled the barrel in my vise, puddled some flux on the milled flat, wiped some more on the tinned underside of the sight, and tapped it in to place. I had to lightly drift it in now, as the tinned bottom made it tighter. finger tighten the mechanically zeroed rear sight on, and used my wheeler laser to bore sight and make sure the front post was dead on center. I then wiped away the excess flus on the outside, wiped the outside with a barely damp with acetone patch, followed by a few swipes of a patch with a little cold blue on it, to keep any excess solder squeezed out when heating from sticking too much.

The milled area as well as the bottom of the site has deep milling gouges swirling around, so I did not feel the need to alter the surfaces to get the solder to stick better. Next, the heat, playing back and forth on the side of the barrel, testing frequently on the top next to the base to see if it melts a piece of solder. once it was just hot enough, I played the heat a bit more on the sight, then ran a bead along both sides. the bead was mostly sucked in underneath, with the excess tinning along the edges.

I heard the kiddos stirring, so I left it to cool while we enjoyed our cheerios on the porch.

I cleaned up the barrel with 320 grit sandpaper, and the excess solder with a fine wire brush on the dremmel. I think it will hold nice, provided I don't go bayonet fighting, and there should be no solder showing when I am done bluing it.

Next up, hand-sand the barrel to prep for bluing, while all my parts soak in the evapo-rust.

I used the low-temp brownells Hi-Force 44 that Doco sent me with his tools. For flux, I had some liquid acid flux that came with a stay-brite silver-solder kit let over from when I built my brewery a few years back when I was a professor and had plenty of time and no money.

[ssgross]

Criterion left a lot a work. I started by cross polishing (lengthwise) with 150 grit and water to see what I was up against, planning to finish at 320 before rust bluing. This showed many areas of deeper chatter scratches that were hiding. They seem to have polished on the lathe with 150ish, but not enough to eliminate all the tool marks. it's going to take a lot of time and patience. I paused sanding, dried off to check progress while I chatted with the Mrs. for not 10 minutes, looked down and saw flash rust spots! Make sure we spray down with wd40 when we are done for the night!

Here is an 8-30 tap I'm thinking about chasing the rear sight threads with.
https://www.mutualscrew.com/product/...teel-85658.cfm