Finland SAKO Cal. .308 AII 3336** Inspected 16 May 1980

Discussion in 'Sako Medium Actions' started by newsakobrass, May 9, 2009.

  1. newsakobrass

    newsakobrass Guest

    Hi, this is my first post.

    I just wanted to say that I've always loved Sako rifles and would like to share some comments and also ask a question or two.

    My first SAKO was a .222 L461 Vixen. That heavy barrel .222 has been my pride and joy for many years but I had a break from shooting for about 10 years but at that stage of my life I reloaded 52gr HPBT using SAKO unprimed brass, IMR 4895, Federal SRP and relied an an old reloading manual.

    I didn't know about twist rate of the rifling or how important the different shape of bullets were or the implication of their weight. My thoughts back in those days was that a .222 Sako was a good rifle and would kill rabbits and put holes in paper; if I used heavier bullets then I could shoot larger feral animals as long as I worked up the loads and used the reloading manual.

    I liked the .222 so much, that I purchased another SAKO in .308 calibre about October 1980.

    The original Brochure that came with the .308 says that the SAKO rifle was inspected in Finland on the 16 May 1980.

    On the front of the brochure contains "check-boxes" , that I presume were crossed with an X by the inspector to indicate the rifle.

    The brochure was crossed as follows, .308 for Caliber, Type was Forester; it also a blue-stamp that said "Sporter". The "Date of Inspection" says: 80-05-16 (16 May 1980) The inspector then initialled the last box.

    On top of the Barrel where the barrel connects to the action it says:
    SAKO
    Cal..308
    On the left hand side of the rifle it says on the action, AII 3336**, (**indicates two more serial numbers) next to that, is a stamping that looks a bit like a kings crown with 3 points and some sort of animal with a tounge, next to that is an R/ shape.

    If possible could someone advise of the twist-rate for this rifle.

    I have searched the old archives of Beretta, I've googled until my eyes are red and I've asked bullet manufacturers about their bullets and the twist rate.


    I've had opinions of the twist rate ranging from 1:10, 1:11, 1:11&3/4, and 1:12.

    Some have said why don't you just push a "tight patch" down the bore and count the revolutions but I'm not sure if I would get the patch stuck or be able to accurately ascertain the correct twist rate using this method.

    Hence, I humbly ask for your advice.

    Regards
     

  2. hayseed51

    hayseed51 Well-Known Member

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    Hi NSB, and welcome -

    If you're really concerned about the actual twist of your barrel, I don't think there's any substitute for measuring it... I've meant to do it for a while, but this morning put together a 'how to' that might be of some help. It should be a sticky post at the top of " Sakos in General" cat. Also, may be in the recent posts on the right for a while.

    Curious if you need the number to plug into an exterior ballistics program, or were planning on tiptoeing around with the long target bullets, or what?

    Fwiw, I have a couple 308 Forresters that I've measured the twist on. they're only about 2k apart in s/n, but a little less than 20 years older than yours. They both check out at 11.75". I can't confirm it, but have a suspision that as the decades went by, they started twisting them a little faster...

    Dick
     
  3. newsakobrass

    newsakobrass Guest

    Ed51

    Thanks for helping.

    I read your post about how to work out the exact twist rate but I'm still having no luck.

    The rods I have, have rotating heads and the brushes fit ok except that they tend to slip.
    I can't get an accurate result.

    I'll give it another go tomorrow with your method and if that doesn't work I'll try something else.

    Some custom builders for Sako actions told me the early 80's models in .308 had 1:10 twist; I need to know for sure because I'd like to use heavier calibre bullets but I don't want to increase the recommended pressure for the action.

    Not knowing the twist rate accurately could mean I'm spending money on bullets and powder that won't stabilize the round and if that's the case my efforts will be fruitless.

    Having said that, I've never handloaded .308; only ever reloaded for my .222 Sako Vixen (1:14 twist, 52gr Sierra HPBT).

    With the .308 Sako which was manufactured and inspected in May 1980, it hasn't had a lot of rounds down range but shoots 168gr ballistic silvertips quite accurately, it also handles 144gr 7.62mm Australian F4 military ammo very well, so, this adds to the confusion.

    I haven't been out to a hundred metre range but the 168's hold a 3 round, 15mm group @ 50M with not much practice.

    The AII/L579 .308 Sako 24 inch barrel, has been a bit of a ghost in the gun cabinet for many years but now I want to reload and hence my request to you guys for the twist rate so I can work out the maximum length and weight of bullet for the occassional "game" - shot

    Regards Jim
     
  4. oblio13

    oblio13 Member

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    Unless you're determined to shoot 220 grn. bullets for some reason, your rate of twist is fine, no matter what it is._
    I use the same bonded-core 168's for everything from antelope to moose. Bullet technology has come so far in the past few years that there's no need for anything else.
     
  5. wookie316

    wookie316 Well-Known Member

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    I agree on the twist rate. I had a Sako TRG-S in 300 Win Mag with a 1-12 twist that would shoot bug eye groups @ 3000 FPS with 200gr Accubonds. 1-12 is fine for a 308.
     
  6. hayseed51

    hayseed51 Well-Known Member

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    Jim -

    Stay after it - you'll get it. You might need to get a better rod. They all rotate, but better rods have ball bearing mounted handles. Maybe try wraping a patch around a slightly undersized brush, and hit it with a little solvent to hold it in place. Make sure to shove it into the rifleing a few inches before trying to take a measurement.

    I tend to agree with Oblio - whatever it is, it's gonna work, and likely work well. The longest bullets I can think of in 30 cal are the Berger 190 VLDs (bc 570) and 210 VLDs (bc 615). Berger reccomends 12t for the 190s, and 11t for the 210s! Only other long one might be Barnes 200 TSX... I think all these bullets though, are impractical in a 308 repeater because their length is just too long to function out of the mag anyway.

    Don't wory about stressing the action. As long as you take the normal precautions and pay attention to pressure indicators of the brass and bolt lift, the extra bullet weight is accounted for.

    Also think the 165-168 class bullets are an awfully fine compromise in a 308. They provide great trajectory and retained energy out there quite ways. Modern bullets, whether bonded, mono, partition, whatever, have great terminal performance. Think you'd be wise to establish a baseline in that weight, and then, if you have the need, experiment from there.

    I have a friend and shooting buddy that relys heavily on Quickloads for load developement. It's a nice tool, and often he will hit a load easily. However, when it doesn't work well, he tends to get paralysed with indecision... Point is just do it! Find a bullet that you want to try, a couple of powders, and expect to spend some time with load workup. In my mind, it's unreasonable to expect to analyse charts, load books, and maybe ballistic software, and expect to come up with 'the' load, or even a good load.

    Think there's a guy that sells bullets by the each over the i-net. Might be bullets.com or something. Doesn't take many bullets to figure out if they're gonna strike nose-on.

    Luck -Dick
     
  7. stonecreek

    stonecreek SCC Secretary Forum Owner SCC Board Member

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    I haven't measured my pre-Garcia .308 Sako, but like Hayseed's guns, I have a .244 Sako which measures (as close as I can determine) about 11.75" . This would be 29.85 cm, so I suspect that the factory spec is actually 1-30 cm. In a .308, this is adequate for the longest 180 grain bullets -- and I can't feature a situation where I would want heavier than a 180 grain bullet in a .308.

    There has been far too much hype recently about "perfect" theoretical twists for particular bullet diameters and weights. As several have pointed out, the 1-12" twist in a .30 caliber will stabilize virtually any conventional hunting bullet. I've seen various guns shoot marvelous groups with bullets that were both theoretically too heavy or too light for their barrel twists. The only way you'll know is to load it and shoot it, and nine chances in ten, if you find a load lacking in accuracy the fault lies somewhere besides the twist rate.


    In other words, don't worry about your twist until and unless you start seeing holes in the target which aren't round.[​IMG]
     
  8. newsakobrass

    newsakobrass Guest

    Thanks Dick and the forum for some very welcome links and advise.

    I've taken on board what seems to be the most important aspect accuracy, not the twist rate.

    Having said that, today I tried in-vain to measure the twist rate which provided mixed results.

    To keep a long story short, I didn't produce accurate outcomes so my method or tools, or a combination of both are flawed.
    Results were between 1:10 & 3/4 inches to 1:11 & 3/4 inches. To me that's not good enough, something inside me just wants to know the exact twist rate and I'm going to get that information.

    Call me stupid or stubborn but I need to know.

    Maybe Sako collectors, are as passionate about their rifles as they are about other aspects of what goes in and what comes out of a classy piece of Sako workmanship.
    For me, all I can say, is that, as I get older I want to pass on a rifle to my son that he will be able to appreciate not only its asthetic appeal and natural accuracy but the technical data that should go hand in hand.

    The .222 Vixen is what I've used mostly, the reason for that is that it is not only a pleasure to shoot but my pride and joy; it cost a lot of money when I was an apprentice, the scope plus mounts were just as expensive as the rifle.

    Where I live, we didn't have large game available so, the .222 was ok for rabbits to kangaroos.

    But things change.

    Where I live now, our game council has given people like myself who hold a firearm licence plus a "R" licence the opportunity to shoot large game such as our largest species of deer, "Sambar".

    We can now access some of our state forests to hunt. I'm not a person who wants to shoot huge deer for the sake of antlers or to say I shot a big animal, but what I would like to do' is use my AII/L579 .308 Sako to wander the hills, enjoy the bush and perhaps take a deer for food.

    Like many of you, the outcome is for a humane kill, respect for the animals and respect for the rifles that we have worked so hard to obtain.

    So, without raving on too much more, twist rate, the bullet and all the components and skills that we learn or know can be passed on to those young ones who want to learn.
    To me it seems that many things are made poorly these days (Sako's aren't) or there's that saying, "that will do" or "she'll be right mate".

    That's not what I'm about; I should know the twist rate of my Sako and I should pass on as much knowledge as I can to my young bloke; to do that, I like and need facts (It's a personal gut feeling).

    Thanks again for your help, I'll get the results sooner or later.

    Jim
     
  9. hayseed51

    hayseed51 Well-Known Member

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    Ok Jim -

    You need to fill in the blank. I can understand and relate to that. Daily, I find myself getting fixated on some minor point that, even at the time, I recognize as being of little practical value. Among friends and family, I'm known as 'The Keeper of Trivial Information' (sometimes 'Useless' is also used). Just a personality trait - I don't see anything wrong with it.

    There is no practical reason under the sun for you to wait until you know the precise twist rate to start load developement. It seems likely that your rifle t is 10.75-11.75".

    As to filling the twist blank, either refine your methods and equipment, or take it to a gunsmith/shop that you respect. You should be able to measure to about 1/4" .

    Good shooting...
     
  10. newsakobrass

    newsakobrass Guest

    Twist Rate


    With the forums help this is how I found out the approximate twist rate.


    SAKO .308 Forester "Sporter" AII/L579 manufactured May 1980.


    Serial Number: 3336**


    I used some of your ideas and came up with this:


    Components:


    One 5mm diam length of "Balsa wood" (nice and soft) dowel from a craft shop.


    One small piece if copper wire from an electric motor 0.5mm in diam (soft, but not too soft).



    Construction:


    From the end of the Balsa-wood dowel, I inserted the thin copper wire so that it passed through the maximum diam of the dowel.


    The length of copper wire was trimmed to 9mm. This (9mm) is a little longer than you would anticipate but the wire bent nicely to fit in each adjacent groove of the rifling.





    Measuring:


    The end of the dowel was carefully inserted from the muzzle end until the wire engaged the grooves of the rifling.


    I gave a slight twist to ensure the thin wire engaged at the intersection of the groove and the land.


    After pushing the dowel about 50mm down the bore, I marked the dowel with a pen at the end of the muzzle.


    Ensuring the thin copper wire was still engaged; I slowly and constantly rotated the dowel 360 degrees.


    As was suggested on the forum, I used a clothes peg on the dowel to provide guidance for the start and end of the 360-degree rotation (Very handy idea).


    Using the perpendicular or plumb side of a wall in conjunction with the clothes peg helped get reasonable accuracy to determine one complete rotation.


    The dowel was again marked at the end of the muzzle after one rotation.



    Results:


    Several attempts provided the following results.


    1st rotation = 300mm


    2nd rotation = 306mm


    3rd rotation = 314mm


    4th rotation = 311mm


    5th rotation = 312mm



    Alternate Method:


    I tried an alternate method, as I wasn't happy with the longitudinal play or movement in the Balsa wood dowel so I wrapped the same thin wire around the solid brass rod sections of my .222 cleaning rod.


    1st rotation = 305mm


    I went back to the Balsa Dowel with a new thin wire and achieved 294mm and 304mm.



    Total results:


    300mm


    306mm


    314mm


    311mm


    312mm


    305mm


    294mm


    304mm


    Average = 305.75mm or 12 inches.



    Thanks for your help.


    Jim

















































     
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  11. Rogan Kinnear

    Rogan Kinnear Well-Known Member

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    Thanks for recording that I formation Jim. Do you, or anyone else, know if it is normal to have that much variation in the twist. Is it common practice to take an average? I'd assumed that the twist stayed the same throughout the machinery's plunge.
     
  12. icebear

    icebear Sako-addicted

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    Sounds like testing variation to me. We are only looking at half an inch or so of difference, which frankly is trivial. I get that much and more every time I check a barrel. I'd say pick a bullet weight that seems reasonable for the average of the twist measurements and don't worry about it. Try a variety of bullets to see what works. Twist is a significant factor but there are plenty of other things influencing accuracy.
     
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