Well for one thing the new M41's do not have a cocking indicator hole, and the other is that instead of roll marked logos, there is some sort of laser etching to take its place. Other than that, they look similar to me. I suppose it is possible to have tolerance differences between a gun made 47 years ago and current production.

I have never seen a slide break or wear out on a M41 - must have been shot quite a bit! I have put more than 15,000 rounds through my 1979 M41 and she keeps on perkin'.

I suppose if your gun was shot enough to wear the slide out, the rails might have worn to the point where a custom fitting is a must for proper functionality. Send it to them and let 'em do their thing! At least this way if you have any issues after the repair, you will have some recourse.

I am just curious...........why do you need a new slide anyway?

Chief38