COL on new Sako Rifles

Discussion in 'Handloads for all Sako models' started by coldsmoke, Apr 8, 2012.

  1. coldsmoke

    coldsmoke New Member

    Forgive me if this item has been mentioned before, yet I have searched for it all over the web and this seems to be the best source of information on these rifles. I own an 85 synthetic & stainless in .270 win caliber, I suspect manufactured in 2011. Do not know how to verify this, yet date is probably within a couple of years. My concern is the fact that I have deciced to now load all of my rounds. After reading every benchrest article on how to load the best ammo for rifles, I was a bit disturbed to learn that to "kiss the lands" on my .270 meant to seat the Sierra 135 grain BTHP to the point that it was not seated to it's correct depth. I have, after some direction from this forum, learned that my rifle wishes to kiss the lands at about 3.469". The SAAMI overall cartidge length is 3.340". I have never shot this rifle anywhere except the range, and don't expect to. Yet when people at the range learn that I am shooting a Sako, they all wish to know all about it's shooting ability. I have read online that the new Sako throats have a forcing cone, which helps center the bullet before entering the lands. This is thought to be a great improvement over the past, yet I still can not believe there are not bullet seating depths which help. I appreciate each who have read this, and more who have considered it. Please help before I reload.
    Last edited: Apr 8, 2012
  2. sakojim

    sakojim Member

    Hello coldsmoke. I am always happy to learn that some one is embarking into the wonderful world of reloading. I would like to respectfully tell you first of all that it is a very enjoyable but serious hobby. 1. There are a number of safety concerns that must be followed. Please study the subject and learn how to recognize excessive pressure signs. There are many good articles available on the web. Most of the bullet and powder manufacturers sell reloading manuals that are a very good place to start. I own about 24 of them and I use them constantly for reference after 40+ years of reloading. 2. "Kiss the lands" is a term for "free bore" distance or clearance. This is one of the most influencial and critical adjustments in reloading other than load selection for fine tuning to get the "sweet load" for a rifle. It is also the last adjustment. Most modern rifles are designed to a specific free bore dimention to allow the bullet to gain movement before engaging the lands to prevent increasing pressure prematurely. I suggest that you follow the COL until you have a reasonably good load worked up and then find some one who is very experienced at reloading to help you with setting the free bore. Most rifle mags are designed to limit the COL for the rifle free bore requirements. 3. Critical measurements: Case cleaning, trimming, inspection, bullet weighing, powder weighing, seating depth are all very important steps to get the best results for your efforts. 4. "Forcing Cone"- I have not heard of this term before. In my opinion the Sako is a top of the line shooting rifle that has near perfect chamber to bore alignment and if the bullet is seated in the correct alignment to the case the bullet will enter the bore in correct alignment before the riflings are contacted. Hope that this helps a little. Good luck and enjoy the process. sakojim.
  3. bloorooster

    bloorooster Moderator

    coldsmoke- First I will say Welcome to the Sako Collectors Club! I have just started handloading myself, so I can't give specific measurements on the .270 yet. What I have been doing with mine is actually measuring the inside length of the rifle's magazine, then dropping off 3/1000's from that and the results have not been bad...some times when a developed round kisses the lands and is then backed off so that it wont stick in the lands and empty your charge down the mag box, it is still too long to fit the magazine....so, to me measuring the magazine box saves a little time! The loads I have played with (from .222 rem up to .308 win have shown groups in the 5's and less...not bad in my book ( my book has mostly pictures) I found also that when you change bullets (type or brand) it changes the seating depth so that part has to be readjusted-Bloo
  4. sakojim

    sakojim Member

    Cold smoke. I neglected to mention one other important factor about reloading. It is a important fact that there is a big variation between the ogives of the various brands of bullets. The newer plastic tipped bullets usually have a more tapered frontal area which moves the point of contact of the ogive to lands rearward if set to the COL and does change the free bore compared to some of the older style blunter bullets. When reloading I have found some slight variation between same brand boxes. I have always checked the free bore of every new box of bullets to set to my specs. There are several ways to measure and set free bore. Check the net for some very good info on that. sakojim.
  5. cmjr

    cmjr Member

    Lot of good advice here but the one thing that I keep getting hung up on is you have a synthetic sporter in 270 and your trying to reach the lands?? I could see it if you were talking about a rifle that you were competing with but your talking about a hunting rifle in a hunting configuration. I would be surprised if you could load the magazine with rounds set up to kiss the lands and I'm assuming you've had to do this for accuracy,it didn't shoot well before? Have you ever chambered a round into the lands to have to take it out and leave the bullet in the barrel and dump the powder charge rendering the rifle useless untill you get it back home to clear the powder. Believe me, anyone that loads into the lands knows exactly what I'm talking about. As mentioned the ojive changes, even on the same bullet. If your an experienced reloader, shoot competitively, messing with COL by setting into the lands can improve a load but not all will improve. The 204 is notorious for shooting with a lot of jump so don't think that by putting it into the lands you'll always improve the performance.
  6. sako-a-series

    sako-a-series Member

    All- what you should be using to determine seating depth is an over all length gauge in conjunction with a modified case. You will also need a good set of calipers which you will find many uses for. Stoney Point makes a simple gauge, and then get the modofied case. So, once you determine the length to the lands, you can back of a few thousands depending on your preferability.

    The instructions are good; I'm sure there are demos on you tube as well.

    Dave
  7. bloorooster

    bloorooster Moderator

    cmjr has touched on a important note in this thread, unless one is shooting serious competition, kissing the lands is really un-needed in a rifle that is gonna be used for hunting or general shooting. I have yet to actually try to set my bullets out far enough to touch the lands, thats why I have been measuring the magazine boxes on each rifle I load for and build the round to fit with minimal clearance. I hunt with all my rifles at one time or another, and with the loads I have been coming up with all my guns shoot sub MOA which is plenty good for any hunting situation...Sure, printing a 5 shot, one hole group is fantastic...but try shooting clays on their sides at 200-300 yrds with any gun you hunt with, when you can bust 'em with one shot no matter where they lay...you got the gun where you need it when it comes to putting meat in the freezer and bone on the wall!-Bloo
  8. coldsmoke

    coldsmoke New Member

    Hello sakojim, I thank you (and all others) for your replies. I will post this paragraph from another site. For openers, your SAKO has a unique throat not found in American made rifles. They use a forcing cone much like a revolver. This helps center the bullet without deforming it no matter if the bullet is seated deeper or not. This is great new technology and will probably start showing up in American made guns. The "forcing cone" technique requires a very hard barrel because it is more prone to throat erosion. Now this was from http://www.go2gbo.com/forums/index.php?topic=92921.0 I certainly do not know of it's validity one way or the other, yet find it interesting. I suspected this sakocollectors site would know more about our rifles than any other.
    Yes, I do realize this is a hunting rifle and not a benchrest gun, but do wish to see it do all it can! As stated in original post, I doubt if I will ever hunt with this rifle so magazine length is not the greatest concern. Of course this would have been, and perhaps will be, the starting point if I can't find someone who has been exactly where I am now. Once again thanks, I appreciate you all. Coldsmoke
  9. stonecreek

    stonecreek Active Member

    I don't know beans about the currently produced Sakos, and can't tell you whether there is any substance to the "forcing cone" hypothesis, but I can tell you that it sounds like either typical Urban Legend or baseless advertising hype.

    Nonetheless, in regard to COL, that SAAMI standard is the maximum length to which a factory cartidge may be loaded and still fit inside the shortest rifle magazine which also meets SAAMI standards. That's all. It has nothing to do with cartridge performance and that length may be much shorter with lighter, shorter bullets. It cannot be longer, except when the cartridge is handloaded and both the magazine and the chamber (leade) allow a longer COL. Which the 3.65" Sako magazines and chambering leades normally do.

    In regard to "kissing the lands": Most loads tend to perform best when the jump between the bullet location and the lands is minimized. TEND TO, that is. My favorite load for my (pre-Garcia) Sako .270 happens to run about 3.29", which happens to be within the SAAMI standard. This is a conventional 130 grain bullet, so it doesn't "need" to be very long. If, on the other hand, I were shooting a 150 grain polycarbonate tipped bullet, it would probably do better with a seating depth of more like 3.45" or so -- and I suspect that at that length it would not engage the lands.
  10. "Kissing the Lands" is not necessarily a technique that always improves accuracy, but it is always a technique that can lead to pressure spikes above the design limits of the case or rifle if done incorrectly. Throw your reloading manual away if you seat on the lands because you have added a variable not considered when the load data was established. Seating on or into the lands is a technique best left to the benchrest crowd & has no real advantage to the sport shooter. Most rifles have a sweet spot of bullet jump that produces good accuracy. It varies from rifle to rifle & load to load. Mine vary from .030" to .120" depending on the gun & load. Some rifles show no difference in accuracy. Seating too long to fit the magazine makes your repeater hunting rifle a single shot, which doesn't make sense in the field. Haven't heard about the "Forcing Cone" thing, but suspect it has more to do with preventing excess pressure spike problems from reloaded ammo done by the inexperienced or unknowledgeable than it does accuracy. Liability concerns are usually the reason behind the so called "improvements", no matter how they are marketed.
  11. cmjr

    cmjr Member

    Coldsmoke, I applaud your efforts to get the ultimate accuracy out of your Sako. You do have some limiting factors though in that the Sporter barrel heats up so quick and your working with a factory barrel and chamber. From a cold bore shot to the 10th round you will have a pretty noticeable drop in velocity, ie a change in POI. Second a factory chamber will not really let you obtain the optimal in accuracy, the loose tolerance that makes it adaptable to various cartridge manufacturer's probably has more to do with the use of a forcing cone. I read the link you posted and frankly PaulS was more on target(sorry/bad pun) than the fellow supporting the forcing cone technology. The concept certainly has merit in a hunting rifle where unknowns and extreme conditions are the norm and a reliable, accurate, and safe firearm is needed, exactly what the 85 was designed to be. As for the accuracy of your rifle they are all different, I would start from a baseline of what it was designed for staying close to spec and go out from there. I would be surprised if you have to go far to reach it's potential.

    Good Shooting
  12. spdrw

    spdrw Member

    Wish you had asked this question months ago. The previous advice would have saved me a lot of frustration. I have a Model 85 Huntere in 260 Remington. Initial accuracy was disappointing, so I bought an O.A.L and proceedd to drive myself nuts trying to follow Barnes advice for seating their bullets. The long leade length makes that impossible.
    Stumbled on the solution when my reloads had to work in two rifles. That meant full case resizing and staying with the max case length. I used one of the canalure like grooves Barnes uses to reduce copper fouling as my crimp location. That dictated the O.A.L.
    It turns out the initial problem was the scope or mounts. Replacing the scope and using the above reloads, the 85 has produced a couple of almost perfect cloverleafs. Certainly more than adequate for hunting purposes and showing off a little at the range.
    Should have "started at the baseline and gone out from there"!
  13. spdrw

    spdrw Member

    Late to the party again. I could have used this thread a year ago.
    I am loading for a Model 85 Hunter in 260 Remington. The purpose is hunting and the enjoyment punching holes in paper between times.
    As most of the hunting is in the lead free Condor range I have used Barnes 120 gr. TTSX and 130 gr. TSX as well as Hornady 120 gr. GMX. Barnes has recommendations about the "jump" that gives best results. From my experiance I would say this is not based on Sako's long leade length. As previously noted, these polymer tipped bullets have their contact point on the ogive more to the rear making it almost impossible to follow Barnes advice, never mind "kiss the lands".
    I find my best solution was to crimp into the appropriate anti-fouling groove which gave more consistant results than all the tweaking I had been doing with OAL. Recently I had to switch from 120 gr. TTSX with H4350 to GMX with RL19. Results were disappointing and just before my hunt on the 21st I found some TTSX. I reloaded for a little more velocity based on working with the GMX. Fired a cold barrel, fouling round and the next three overlapped which I measured as less than .500". That's the best group the rifle and I have ever done.
    Previously I had been very satisfied with a sub .750" made with a 120 gr, Nosler BT. These are for paper punching or the chance that I get a deer tag out of the lead free zone. Should be easier cleaning, too.
    For my needs, keep it simple would have been good advice.
    Good luck with the .270 and avoid "touching the lands".
  14. Paratroop

    Paratroop New Member

    That "forcing cone" sounds a lot like the "free bored" throat used in particular by Weatherby in the past. The idea is to allow the bullet a place to go easily so the space the heavy charge of powder operating in is increased - preventing what would be a dangerous pressure spike. If you try to abridge the free bore you also need to drop your load way back for starting point as the data for free bored rifles does not equate to the standard reloading data unless otherwise noted in the data being used. I agree with the others suggesting you leave the touching of the lands to those pursuing bench rest records. COLper the manual is usually the correct place to start. You might want to get a COL comparator - a device which lets you compare the overall length based on ogive shoulders which varies quite a bit with bullet type and brand. Again, measure your magazine's length first as it is often the determining factor.
  15. pk1

    pk1 Member

    Just reading this thread this morning and find it very interesting.

    I have a Vixen 222 Rem mag and tried loading it to an old standard that I had worked up back in the 60's with a Remington model 722 which gave me phenomenal accuracy. I tried seating the bullets near the lands but the throat was so long I couldn't do it. Even seating the bullet to a safe minimum depth made the cartridge too long for the magazine. I wouldn't have minded so much if the accuracy was there but it wasn't. I have an old time friend who along with a number of other talents is a gunsmith. He purchased a Vixen like mine and was having the same problem so what he did was reseat and rechamber the barrel to shorten the bullet jump. Accuracy improved dramatically. What I did was to convert the rifle to 223 Ackley Improved with a Krieger barrel.

    I really don't know what to make of the forcing cone comments in regards to rifles. Forcing cones were put in shotgun barrels and was a new technology back in the 70's or 80's. Back near the chamber of the shotgun the barrel had a point where the shotshell could open up and lay flat while the wad and shot continued down the barrel. The transition was abrupt. Someone figured out that this caused higher pressure which translated into higher recoil and more pattern destroying deformed shot leaving the barrel. In a game like tournament trap where one missed target could cost you thousands of dollars gun makers were making adjustments like forcing cones in order to deliver a near perfect pattern and ease the recoil some. I take it that the throat in a rifle with a forcing cone is tapered to help straighten out the bullet when it's fired. Face it, there is a thing called bullet tip when the throat of a barrel is too long. It's caused by an miniscule difference in the pressures from the ignition of the powder and an improperly trimmed cartridge case. Seating the bullet out to the lands helps to minimize this but it is certainly no cure all. As mentioned above a man could feel a fool to seat to the lands on a nice cold winter day and then drive a few hundred miles to hunt on a nice warm day. You chamber a round in the morning then don't see anything to shoot at and then take the cartridge out of the gun only to have the projectile stick in the lands and dump all of the powder into the magazine. You then frantically try to find a way to remove the bullet from the barrel so you can continue to hunt. I've been there. It makes you feel really stupid.

    There is another problem as well. A lot of years ago I had a Forester in 243. A guy at our club told me about seating out the bullet to gain some accuracy so I tried it. A friend and I went out calling coyotes and on a daytime stand I called one in that came at me so fast I didn't have the time to take a shot. The coyote jumped on me and tried to bite my face. I was using my rifle to block the coyote and push him back. He kept coming at me until I pushed him hard to the ground. He jumped on me again but I had the end of the barrel touching his chest and pulled the trigger. The gun went off and he fell to the ground only he wasn't even wounded. The barrel was laying across his chest and the bullet missed him. I stood and jacked another round into the chamber only I'd seated the bullets out too far and being in the hurry that I was the cartridge went into the chamber slightly crooked causing the bullet to turn 90 degrees and jam the rifle. The coyote got up and trotted off while I stood helplessly and watched him go. A lesson learned for sure.

    I sincerely believe that a hunting rifle that shoots well is all a guy needs in the field. I tune up my hunting rifles to shoot the best they are capable of but unless I'm getting groups that look like a shotgun pattern at 100 yards I'm happy. I have a friend who takes his rifle to the range to site in for deer and such and is happy if he's in the black at 100 yards. He teases me for being meticulous and he may be right since he is every bit as successful as I am and has killed deer and caribou on our hunts together.

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