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"Pine Tree" or "Christmas Tree" and Bore Condition

9K views 37 replies 19 participants last post by  joe7170 
#1 ·
Hello All! After pondering the excellent information in the thread regarding bore condition and inspection marks used to indicate bore condition:

http://forums.gunboards.com/showthr...h-Buttplate-Bore-Condition-Markings-Explained

I wondered if there is a correllation between those inspection marks, and the "Pine Tree" or "Christmas Tree" chamber markings on barrels that have been set back, or otherwise had work done to the barrel or chamber. I'm just wondering if a =IV= would appear on the buttplate for a rifle that has had the barrel set back and rechambered. I'm guessing not necessarily so - I once had a Yugo M48 that I put so many rounds of Turkish ammo through that the leade was eroded forward about an inch or more; the rest of the bore (and muzzle) looked new.

For that matter, is the "Pine Tree" marking strictly related to Civil Guard ordnance work? It seems to be most common (but is not exclusively) on 91/24s; if I've overlooked references from which I could learn, please let me know!
 
#2 · (Edited)
My "Unmarked" M24, that doesnt have any C.G. crest, or serial, just the S number on the top of the receiver, and the side of the receiver, and just has a =S=, has a Christmas tree mark and was set back, No markings on the buttplate to designate bore condition. Even though my barrel has been set back, the barrel still has a shine to it with very strong rifling and shoots very well.
 
#4 ·
CH:
If present, does the 36(S)00 indicate pressure testing, and perhaps necessary when a barrel has been set back a specific amount (with the chamber now extending past the thickest part of the barrel)? Is this stamp specifically Civil Guard usage?
 
#5 ·
Yes, it is pressure test mark SAKO introduced in mid 1930s during m/28-30 production. The earlier ones don't have it and most definitely it shouldn't be present on a regular m/24 unless it has has revisited SAKO for new pressure test. Those with set back barrels seem to have it and I'd like to see if there are any exceptions. The Christmas Tree & set back barrel correlation theory seems to have a lot more flaws although it still remains very popular explanation.
 
#9 ·
Someone with several m/24s could possibly make chamber castings or do handload tests with different cartridge overall lengths to see whether or not the Christmas Tree is related to throat shape.

I've seen an m/28-30 made in 1936 which has the 36(S)00 proof but I'm not sure if some of the later 1935s could have it too. These mid production guns seem to be uncommonly seen somehow. There also appears to be sort of transition in the bolt numbering from "two last digits & S number" to "four last digits and no S number" somewhere in 1934-35 but there doesn't seem too many unrefurbished samples around to study this further.

Arma Fennica 2 says that m/24s with swollen chambers were fixed by SAKO in 1937-38. Quantity of rifles fixed is mentioned to be 5100 pcs.
 
#10 ·
The "Christmas Tree" marking doesn't necessarily mean the barrel was set back. You can usually tell if it's been set back by just looking at it - even in pictures. The barrel threads are about 16/inch. They are probably metric, but I've measured them and it comes out real close. Sooo........in setting the barrel back, it would have to be done in multiples of 1/16 inch to keep the extractor groove timed correctly. That's pretty easy to see. I've had a bunch over the years and can say with certainty that some with the marking weren't set back. Period.

What does it mean? I don't know. I've heard some theories but can't prove any of them.

I think this theory is like the m/39's have heavy barrels. The don't. I suspect the Century started this and it stuck - and still does to some folks.
 
#12 ·
The "Christmas Tree" marking doesn't necessarily mean the barrel was set back. You can usually tell if it's been set back by just looking at it - even in pictures. The barrel threads are about 16/inch. They are probably metric, but I've measured them and it comes out real close. Sooo........in setting the barrel back, it would have to be done in multiples of 1/16 inch to keep the extractor groove timed correctly. That's pretty easy to see. I've had a bunch over the years and can say with certainty that some with the marking weren't set back. Period.

What does it mean? I don't know. I've heard some theories but can't prove any of them.

I think this theory is like the m/39's have heavy barrels. The don't. I suspect the Century started this and it stuck - and still does to some folks.
They are indeed 1/16". There are no metric fasteners used on Mosins: everything but the barrel/receiver interface are 55 degree whitworth of various sizes, but according to 7.62x54r.net, the barrel threads are 60 degree.
 
#13 ·
The "Christmas Tree" has nothing to do with the chamber being reset. The answer has been found in Finland in official documents although I have been asked not to reveal the reason. Let's just say I'd advise you NOT to shoot the guns with surplus for your safety and that is all I can say.
 
#22 · (Edited)
For the record, S.Y. announced in 1932 that Russian 7.62 m/m cartridges with the following headstamps or ANY OTHER cartridges with large (Russian style) berdan primer were NOT ALLOWED to fire in any CG rifle. They were allowed to use in machine guns only but guardsmen were notified to stay tuned for duds.

As to reloading section in the same book, only VPT cases were allowed to use for this.

 
#23 ·
This seems silly/stupid to me.

The whole point of the Finns adopting an M91 pattern rifle was to use up stocks of rifles and ammo, while preserving the ability to use future capture stocks.

Was it a "during peacetime" caveat related to the Russian rounds putting more wear and tear on the guns or something?

These guns had standard .311" diameter bores, I believe, so it's hard to imagine what was wrong.

Unless maybe the chambers were oversized and they wanted to use stretchier brass cases in them?
 
#24 · (Edited)
I understand your point Claven. The CG definitely tried to improve on accuracy and the SA were pulled along. It appears the .3095" groove diameter started with the M24 and remained a standard for Finn army rifles until the early 1940s.

Among the many factors affecting accuracy was throating. I believe CH is on a good track in that may be a clue to the tree markings. Perhaps the throats were cut for a long bullet like the 12 gram 108A, tree marked and later set back and cut with a shorter throat.

There is so much more to the Finn barrel issue than bore and groove diameter.

Long gradual throats like the "D" modification made the tight bore rifles more forgiving for use with captured ammo as well as Standard D166 ammunition.

I had a nice unmodified "F" marked M27. The throat was short, sharp and abrupt when compared to a Russian or Soviet rifle much less a D modified Finn or M39
 
#28 ·
I've seen at least two Remington and one NEW M91 with the tree stamp.

I'll see if I can dig up the pictures.
 
#29 ·
It's purely conjecture on my part, but consider the following possibility. We know that there are rifles that have the mark in question, and that have NOT had the barrel set back. We know that there are rifles marked with the "tree" that do not have the 36(S)00 pressure test proof. If it could be demonstrated that rifles with the shortened barrels always have the pressure test proof marking (as I seem to remember being a possibility stated by others), could the "tree" mark be preparatory to maintenance that was considered critical? That is, a barrel is examined, and it is determined to need the ordnance procedure for whatever condition - it is stamped with the "tree," and set aside. After rework and (pressure) testing/inspection, the now "good to go" barrel is stamped with 36(S)00. Again, just considering the possibilities.
 
#30 ·
This thread had me round up an oddball M28 that has been in hiding here for some time. I snapped some pics and have added them to the mix. No Christmas Tree but the barrel is 36S00 marked and is set back a considerable distance. So far back that only the leading edge of Tikka Triangle can be seen and the number 6 in the serial number left side of barrel shank is completely missing. There is a long void in the wood in font of the barrel step. Rifle has D chamber stamp, M39 trigger w/mousetrap spring and no "M" stamp on the rear sight base and is pretty much a total mismatch. Seems to have made more than a few trips to it's units Gun Doctor!
 
#33 ·
I had a nice unmodified "F" marked M27. The throat was short, sharp and abrupt when compared to a Russian or Soviet rifle much less a D modified Finn or M39[/QUOTE]

Hey you are the first one to post about that and I too have an older Unit Disc rifle that is very picky about ammo it will chamber and shoot. Head space is not an issue and once it gets ammo it likes it is a jewel to shoot. Ken mine is F marked too. Bill
 
#36 ·
I'd bet it was merely matter of brass quality. Both VPT and Sako used VPT brass. Good brass has better chances not to rupture in faulty chamber.

As a side note, at least since 1932 it was also a CG regulation that only VPT brass is allowed for handloading 7.62mm ammunition.
 
#38 ·
This thread reminds me I need to look at the M24 I am considering buying out of a collection. I know its a pine tree, and has 2 S numbers, but I don't recall if it had the 3600 proof.
 
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