Finished a long term Build, but it's a little different

Wapiti1

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Valmet 412S 3 barrel set. 3" 12gauge OU, 30-06 double set and this set that I finally finished. It started life as a .375 Winchester barrel set, was rechambered to .375 JDJ at some point and is now in .375 H&H Flanged Magnum, the rimmed version of the .375 H&H Belted Magnum. I've been looking for this barrel set for about 3 years and finally found one for a fair price. I pulled the whole thing apart to measure the tenon dimensions and make sure it would be safe, then reamed them to the new chambering and reassembled it.

This completes what I consider a hunt anywhere for anything rifle package. A bit different than what is usually shown here, but a really fun and useful package.

The whole package has two quick detach scope mounts, with a Nikon 1-4X20 Monarch in one, and a 3-10X42 Swaro Z3 in the other. The peep on the .375 set shown has been removed and an express sight added to the rib.

In case you are wondering, the weight of the receiver and 30-06 barrel set is just under 8lbs. With the scope it is right at 9. The .375 set weighs 9.5 with scope and the 12 gauge OU weighs 6.75.

For now, it is ready for some paper killing.

Jeremy
 

Brendan

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Very cool. Going to need to see some more pictures of this one. I know nothing about these guns except what I've Googled up in the last 5 minutes. Valmet 412S? Finnish gun that later became a Tikka 512S?
 
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Wapiti1

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I'll snag some more shots of it this evening and post them.

Not a super fancy gun, but they were not intended to be. They were intended to be a platform where you could mix and match for your needs that day. All without being out of reach pricewise. The progression was 412, 412S, Tikka 512, and Marocchi 612. The 512 and 612 were made in Italy, the 412's were all made in Finland. The Finn guns are considered to be the best quality, but the Italian guns had nicer wood. They came in single mechanical trigger, and double. Mine is a single, and I have the parts to convert, but doubt I will.

Marocchi stopped making it a couple of years ago.

Barrel sets come in a wide variety and many combination shotgun over rifle sets.

Jeremy
 
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Wapiti1

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More photos as requested.

A few more details. This is a nickel plated receiver in satin finish, obviously. They also came in gloss blued with gold lettering.

The original design is from Remington made as the model 32. It features an over bolting system that you can see in the second to last photo. The whole top shroud slides back and locks on both sides of the barrel at those small beveled ears. At the bottom of the barrel mono-block is a protrusion that mates to a recess in the receiver. This locks it tight, and makes the system extremely strong. The original Remington didn't have that feature, and early Valmet Lion models the cloned the Remington didn't either. They added it to the 312 which you rarely ever see, and it stuck with the improved 412.

One thing most folks don't know about doubles (OU or SXS) is that the barrels don't lock at 90 degrees to the breech face. They are actually negative by 1-3 degrees, so they over rotate a degree or so. This means that the thrust of the case against the breech actually forces the barrels closed tighter. Well designed doubles can be shot without the locking bolt in place (don't try this at home or anywhere else).

Anyway, as you can see 3 barrel sets. 30-06, .375 H&H Flanged Mag, and 12 gauge 3" with interchangable chokes. The rifle barrels are all 23.75" and the shotgun set is 26". I need to get two cases. One for all of it, and one two barrel case for travel. Say I go to Africa. I would take the 12 gauge set and the .375 set. There is some great wing shooting in Africa, and the .375 set will handle all the other game up to elephant. If I go to Montana, I'd take the 30-06 set and 12 gauge set.

Accuracy is unknown, but I've been told is very good. The regulation (where the barrels shoot relative to each other) is user adjustable, which is not normal, but really nice. I've been told that regulating both for good accuracy out to 200 yards is very doable. One barrel alone is as accurate as the load it likes, so shooting farther is a single shot deal.

I have a single trigger on this one, and it is selectable for top or bottom barrel. It is also mechanical, not inertia. That is nice since you know it will go boom. I also have the double trigger set, but am not sure if I'll install it or not.

The velcro on the stock is for a detachable cheek riser. I'm not sure what I'll do there yet. I don't like that setup, but need the riser for scope use. I'll probably add an adjustable comb to the stock.

Jeremy
 

AgentVenom

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Very nice set up! Silly question since it can handle ‘06 why did you go with .375 flanged instead of the standard .375 H&H. My curiosity I know most doubles shoot rimmed cartridges. I was a poor soldier when I came across the Tikka 512 with 4 barrel sets (.308, .222, 12 ga and 9.3x74R) couldn’t float the $2k asking Pity
 
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Wapiti1

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Very nice set up! Silly question since it can handle ‘06 why did you go with .375 flanged instead of the standard .375 H&H. My curiosity I know most doubles shoot rimmed cartridges. I was a poor soldier when I came across the Tikka 512 with 4 barrel sets (.308, .222, 12 ga and 9.3x74R) couldn’t float the $2k asking Pity

Back thrust of the belted .375 H&H is quite a bit higher than the 30-06 even though they operate at similar pressures (62ksi for the .375 and 59ksi for the 30-06). The lower pressure spec for the .375 H&H Flanged, at 47ksi, puts it almost equal to the 30-06. So, well within safe limits where the belted pressure is over a known safe back thrust.

The back thrust is calculated by taking the area of the internal section of the case head and dividing the max pressure by that. Some use the outer rim diameter, but that is for comparison purposes, IMO. You want exact numbers if you are talking safety limits.

I pulled the barrel set apart prior to rechambering so I could check the thickness of the barrel tenon as well. Kind of a PITA, but better than losing some fingers and an eye.

The .375 H&H Flanged Mag scoots a 250gr bullet at about 2600 and a 300gr at 2400, so it isn't missing anything.

Too bad you didn't pick up that set. It's a really interesting platform. Certainly unique. We'll see if I like it over the long haul or not.

Jeremy
 

RgrLW2012

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Great to see someone else using a 412/512! During the pandemic my fascination with Finnish hunting videos turned into a 512 w/ now seven barrel sets (30-06 o/u, 30-06 x 12 ga, UL 12 ga o/u 28 in, 12 ga x 12 ga rifled, 12 ga o/u 24 in, 20 ga o/u, and 9.3 x 74r o/u). Curious how hard it was to disassemble the barrel sets and how much material you had to work with? An idea I was playing with is to find a .223 o/u barrel set and ream to .350 Legend for SW Michigan deer hunting.
 
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Wapiti1

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Great to see someone else using a 412/512! During the pandemic my fascination with Finnish hunting videos turned into a 512 w/ now seven barrel sets (30-06 o/u, 30-06 x 12 ga, UL 12 ga o/u 28 in, 12 ga x 12 ga rifled, 12 ga o/u 24 in, 20 ga o/u, and 9.3 x 74r o/u). Curious how hard it was to disassemble the barrel sets and how much material you had to work with? An idea I was playing with is to find a .223 o/u barrel set and ream to .350 Legend for SW Michigan deer hunting.
The Valmet made barrels are not easy to get apart. They are silver brazed together and a bear to get apart. I will never tear one apart again. If I wanted to do another custom barrel set, I would find a 12ga set, cut the barrels off, ream out the chamber stub, and then thread the mono-block. Then fit the new barrels with a threaded connection instead of brazed and make the other attachment hardwear.

I don't know how the Marrochi barrels are put together since some were carbon fiber clad.

I would love to have the 7X57R barrel set they offered, but rarely see them at all.

Jeremy
 

Macintosh

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This is very, very cool. Thanks for posting! I'm curious about how you'll handle the comb, as with a shorter-barreled shotgun being a key element I wouldnt want to add too much weight back there and affect handling. I'll be curious to follow along on that part if you care to share.
 
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