Reindeer , if you cut on a lathe the face of the barrel to adjust the 0.05 mm and then you re-face the bolt to square it removing the 0.05 mm you end with no gap , ( or cut the chamber 0.05 mm deeper) the gap maybe more accurate but I dislike it there .
Saludos

Daniel

For what its worth an FN is not a Mauser M-98, its an FN, close but no cigar...This is a common error among riflemen. I got properly scolded by Jack Belk for that mistake at one time.....

I am in a project of sporterizing an 98K, in 30-06 which I have done a few times before and now I am facing some questions I would like to get an answer to from an experienced professional or home gunsmith

I used to use Mauser 98 K actions, stamped pre-war or no later than 1942. These are more and more difficult to get, at least in a decent condition.

FN Belgium produced short barreled 98 rifles for law enforcement after the war. Most of them are in mint, sometimes arsenal condition and can be had for as little as Euro 100,--

I got one of these, took it apart and had a close look at it. It struck me that these receivers don't have the common internal C-ring like the German Mausers, but two opposite cuts in the ring. For the rest they are identical to the military style German Mausers.

I did the usual work: lapping the lugs, lapping the notches, squaring the boldface and squaring the reiverhead. I only had to take away a thin sharp brim off the receiverhead, probably caused by fitting the original barrel by FN, because I found the receiver square enough as it was.

I ordered a chambered and threaded stainless steel match barrel from Lothar Walter in Germany and when it arrived I screwed it in to see how it looks. I didn't tighten it because I want to apply a baked on PTFE coating on the action, whereas the barrel will be glass pearl beaded

I used some lamp black soot to see if the barrel met the two internal notches and it did, but there is a slight gap visible between the receiverhead and the shoulder of the barrel. It measures about 0.05 mm. It may become less
when I tighten the barrel, but it looks like a slight gap will remain here.

I know that some riflemakers allow such a gap on purpose because they claim it benefits accuracy. Steyr in Austria does it this way with their heavy barreled match and varmint rifles.

My questions are:

Has anyone ever worked with these FN actions or similar ones without a C-ring and do you consider them as strong and safe as the ones with a closed C-ring?

Is there a known difference between Begian FN 98 receivers, and the German 98 Mausers?

Do you think that a slight gap between receiver head and barrel shoulder would be allowable or would this be detrimental on the strenght and safety of the barreled action?

Of course I will measure headspace before firing the first shot, but since I make my own ammo, I'd rather fireform my cases for this chamber and leave the gap as it is, that is when this is safe to do and when headspace is within acceptable tolerances.

I would be very grateful for any comment on this and for any other good info on sporterizing 98 actions.