My Sky M39.

[finloq]

I'll give you this, Lee: You have great taste is rifles and a knack for close up pictures.

[Lee-online]

I'll give you this, Lee: You have great taste is rifles and a knack for close up pictures.

When I see a rifle, I know right away if I want it, if I do then I buy it. Some other rifles just work on me until I submit and then go and buy them. others I don't even give a second look.
As for my pictures, they are taken with and older cannon powershot a510 that is dyeing, I have to flick the lens to get the shutter to open. I use it at work to take picture for my reference so I can put the things I take apart back together.

Still didn't get to fire this rifle yet, I have a new firing pin and a sling inbound from liberty that should be here in a few days. I'll wait for the new pin before firing it with the dull one in the rifle.

[Sirex]

Very nice! My 1944 Sako with very little blue left, hodge podge of parts, and rough stock is probably my favorite rifle to shoot. It goes out with me the most, and it's like my old pick up truck I had as a kid. Not beautiful, in fact rough, but comfy and always ready to rock. Don't have to worry about scratching the paint. One of those carefree ones. Yours looks really cool.

[shmlnaaa]

I like the prop. I like the rifle even more! WW2 m/39's are some of the collect Mosins there are IMO.

[Flyin Brian]

Very Nice Sk.Y M39, that model is one of my favorites. Looking at the receiver pics I was thinking maybe I could make out a Chattelerault stamp somewhere but I don't see it. Basically the early Chatt. receivers were not marked on the tang, but the first 2 years (I think) had grease holes (I don't see it on yours) and they started marking them in 1894... so If you can find a Chattelerault mark somewhere, you could pretty well establish it as an 1893 receiver

Along the bottom of the receiver flat (behind the recoil lug) is there any stamped letters that are in a small shield maybe? Some of the marks look funny sometimes.

Here's an 1892 or 1893 Chatt with the grease hole. The "P" stamp is sometimes an "L" or an "E" too:

[husker51]

[zeebill]

Believe it or not that pin punch mark on top means something! Just what I am not at all sure of but I see marks all the time over there, 2's 3's, and 1's too or should that be two? When they are on the side of the receiver they were a crude sort of hardness test the Finn's did on the receiver before they did their magic on them. Bill

[Junk Yard Dog]

Testing the hardness when the receiver is already 40 years old, or older, I am not sure I would want to know by that point.

[Lee-online]

I'll have to take it down again and look but I didn't notice any marks. There is the L on the top side of the receiver.
I just picked up a M27 and will take that apart first.

[Lee-online]

We use the Brinell hardness test at work occasionally. Basically you put a dimple in the metal with a center punch and then put a mark on a control metal bar that is divided and marked with different hardnesses. When you make a mark the same size as the one in the thing you are testing you have found the hardness. Crude but it works as long as you use the same force, same punch and same hammer.

[Junk Yard Dog]

How can you be sure you are applying the same force with the hammer each time? Things like fatigue, would come into play, I know I swing a hammer with less force by days end than in the first hour of the day when I am fresh.

[Lee-online]

If I want to check the hardness of a spool in a hydraulic valve. I'll use a small ball peen hammer and strike the punch from 10". Then lay the control next to it and do the same on all the different hardnesses. It gets a good enough reading to know if the spool is hardened to the approximate spec or if something has not been hardened at all. I have only checked something maybe twice in the last 10 years, valve seats that leaked because they were not heat treated.

[Junk Yard Dog]

Well, the Finns went on the use the receiver so I suppose whatever they found it wasn't bad. The failure rate of Mosin receivers is surprisingly low considering the huge numbers produced under wartime conditions during two world wars. We have heard of a few that have cracked, there used to be pics someplace of just that happening to a 30's date hex I think it was, but considering the long use these rifles saw, and the abuse, as well as the stupid shit people do to them now they hold up very well.

[zeebill]

Many years ago when I first noticed Mosins I was concerned with the age of some of the older receivers so I stripped them down and carried them off to work on a weekend. At that time they still had weekend coverage and I grabbed the engineer in there and swore him to secrecy so I wouldn't lose my job and he tested them using modern methods. Don't ask me what he did as I was off on the job I was called in on but when I picked them up later in the shift he quote said that is some preety good steel for being as old as it is! He said they were about equivelent to a grade 3 bolt which was good enough for me. Bill

[bunkysdad]

Some type of spring loaded punch that delivers the same blow every time, like a automatic center punch.

[Junk Yard Dog]

I would prefer grade five, but grade three is more than enough to get the job done with no difficulties.

[Junk Yard Dog]

Make the steel too hard and it will crack, lower hardness steel is much more flexible, capable of withstanding a pressure spike hundreds of thousands of times. This is were the heat treatment process becomes so critical, and in the Mosin era was an art form controlled by the human eye, today it's al managed by machine of course.

[zeebill]

I would prefer grade five, but grade three is more than enough to get the job done with no difficulties.

The higher the grade the generally more brittle the steel is and you for sure don't want brittle steel in a receiver. Going over in the needed grade of fastener was generally the reason things failed when racing them. Bill

[Junk Yard Dog]

That's why the head studs on my A are grade five as originaly called for and not grade eight that some modern thinkers like to use.

[zeebill]

Many foolish people spend buddles of money putting grade 8 fasteners througout their cars and then wonder why things crack and break. It is one area of strength that the strongest aren't always the best. Money doesn't always cure everything unlike the government thinks! Bill