Sako S20 Precision rifle - test & review
PUBLISHED: 09:47 18 September 2020
Consistently accurate straight from the box; great balance; smooth bolt operation! Broadsword is full of praise for the Sako S20 Precision in this review
I can’t remember when there has been such anticipation for the launch of a new rifle and boy does the new Sako S20 exceed one’s expectations. Classed as a true hybrid rifle model, Sako have rewritten the rifle design book and produced a gun that, like a Chimera, has two DNAs running in one body/chassis.
On the one hand, there is an ergonomic thumbhole Hunter design that achieves great stability, looks and features for field use. On the other, with a few quick turns of the Allen key, the Hunter is turned into a Precision shooting machine wearing a completely different stock system, perfect for long-range use.
With a one-piece chassis aluminium system, guaranteed MOA accuracy, new magazine and trigger design as well as tough Cerakote finishes, numerous M-Lok attachment points and integral Picatinny scope mount, the S20 adds up to quite a rifle.
The choice of calibres available from GMK are: .243, .270, .308 and 6.5 Creedmoor (listed on the website), and the S20 is also made in .30-06 Spring, 6.5 PRC, 7mm Rem Mag and .300 Win Mag, all of which proved a perfect array of calibres for GB usage.
The whole S20 is built around an internal aluminium chassis system to which the S20 accessories are attached, thus allowing a high degree of flexibility, while maintaining great overall strength and integrity, with recoil kept parallel to the bore. It is made from aircraft-grade aluminium so it is lightweight with maximum stiffness and longevity, while remaining impervious to the British weather! The polymer stock system means there’s no chance of warping that would affect accuracy and consistency, alongside a black anodised non-reflective finish.
That’s all great but a good bedding system is also needed and Sako have opted for an angled chassis with a full ‘V’ bed system where the union between action and chassis is consistently held along its entire length. Bit like the old Tikka M65A sniper rifle I owned, it’s secured to the chassis by a three-point attachment system, like the Sako TRG rifles.
The action itself has several features of note. Gone is the classic Sako dovetailed scope-mounting system; enter the new universal Picatinny rail that is machined directly into the top of the action, so there’s no chance of anything working loose. The stainless-steel bolt has an interchangeable bolt handle that can be customised to your tastes but the baton-shaped three-grooved standard version was good enough for me. The bolt is long at 7.5” and has the characteristic three locking lug system enabling both a low bolt lift and providing a good surface area from the lugs to evenly spread the pressure. Providing Sako’s familiar ultra-smooth non-binding bolt operation.
This uses a push feed from the magazine system and the extractor claw, which is often copied, and provides reliability and assured extraction of the fired case with a sprung plunger set into the face to ping out the empties with the bolt fully retracted. As is the case with longer actions, you do have to lower the cheekpiece to remove the bolt.
The trigger and safety hold a few surprises too, being adjustable for length of pull and pull weight. You can move the trigger blade backwards 3mm or forwards 4mm with an Allen key so a for optimum comfort, which is a handier feature than you think. The weight of pull can also be adjusted from 2-4lb; the rifle on test broke at 3.25lb dead. You can also specify a single-stage or two-stage trigger as your preference.
Safety wise, you have Sako’s typical lever system with forward to fire and back for safe with a blocker stopping the firing pin moving forward so any knocks or drops will not allow the pin to strike the primer. Nice! You also have a small additional push button to allow the bolt to open with the safety on to unload.
The S20 features a glass-reinforced composite magazine in a staggered column five-shot design with a 10-shot option and magnum calibres with three- or seven-shot capacity. I like the release lever, which is sighted at the front of the magazine, but it does make it a tad rattly when unloaded. Another great feature, if you are a reloader like me, is that the magazine’s internal length, which is lengthened so that you can seat bullets out further to seat them closer to the rifling, still maintained perfect feeding, a particularly nice touch for all the reloaders out there. Cartridges are also supported by the shoulder with a space between the tip (meplat) and mag wall, preventing bullet damage under recoil.
I had a .308 Win version with a 20” fluted barrel length, 18mm diameter in stainless steel and then Tungsten Cerakoted for added protection. This is a great set-up for improved handling, ballistics and weight from a .308 Win, without compromising accuracy or down range ballistics. You can choose a blackened steel version as well as unfluted 20mm diameter plus barrel lengths up to 24”.
Sako use the cold hammer forged process to make their match grade barrels, which changes the steel molecules to produce a work-hardened structure so longevity (i.e. round count) is increased, as is straight out of the box accuracy.
Sako also hand check and test fire every barrel to guarantee sub minute of angle (MOA) accuracy. Cold hammer forging and annealing, elevates imperfections and achieves a smooth bore surface and excellent rifling profiles, so barrels foul less and concentricity of the bullet down the barrel is optimised.
This Precision approach resultsin a 20” barrel and 5/8th 24 pitch finer muzzle thread for a moderator and reduced weight courtesy of six-barrel flutes and all finished (as is the action) with a tough Tungsten Cerakote coating.
This is where the magic happens and where the S20 achieves its hybrid status. You have a choice to change between Hunter or Precision stocks. The Hunter is the thumbhole versions for better rifle control and stability while in the woods or field, while the Precision version has a more range-practical profile, created especially for long distance and precision shooting.
Both have the same instant take-down facility with the use of the universal S20 tool. Loosen the top Allen screw at the rear of the action tang, followed by the bottom screw through an aperture in the trigger guard. Now the rear stock can be slid off the chassis assembly, making for ‘short storage’ of the S20, without the need to remove the scope from the rifle and thus any potential loss of zero.
It’s an incredibly simple yet strong system that tightens on a wedge-profile securing lug that does not move, contort or flex at all, yet with a few turns and the S20 is in two pieces and able to exchange stocks etc.
The fore-end on the Precision has numerous M-Lok fitments for bipods and Q/D sling attachments. Removing the rearmost M-Lok attachment point allows the outer fore-end shell to come off and then the fore-end chassis to be removed from the action. It can be then exchanged for the Hunter version if you like or you can mix and match between the two, the choice is yours.
The rear stock has a quick-adjustable cheekpiece with a push of a button (bit of a knack) to raise the 5” long cheek piece up in six defined steps for 1.5 extra inches in total. Length of pull can also be adjusted with spacers and can also be adjusted for angle and pitch to suit even the most discerning shooter.
Other accessories include a barricade stop design that can be attached in front of the magazine, allowing the shooter to support the rifle on barricades or obstacles as the name implies.
A really handy addition is the optional rear-mounted monopod, which provides great stability and can be quickly changed to adjust the height, locking at 45° or 90° angles and then folded away forward when not needed – very handy.
Two thumb rests are optional, allowing your thumb to rest on either the left or right side of the precision stock. I did not try these, although the muzzle brake is a nice option, either used as intended or as an extended muzzle protector.
In the Field
Fitting a scope to the S20 could not be easier. The integrated 7” long Picatinny rail accepts any such mounts but Sako have a new one-piece aluminium and steel mount. It clamps front and rear and the bridge section accepts a variety of different heights and ring sizes, as well as a variety of positions to accommodate long or short scopes.
The rings have six locking screws, providing a solid and even pressure to the scope tube for a secure grip without any risk of distortion.
The only points I would change would be the rattle from the magazine, which is easily cured with fuzzy felt plus a slightly longer cheekpiece for my particular face profile. I fitted several scopes and sound moderators as well as changing the stocks from Hunter to Precision but primary tests were with the Precision set-up. I shot different factory, reloads, steel targets and went stalking too to give the S20 a real work out.
The S20 proved its MOA credentials with the vast majority of factory loads which is impressive considering the different manufacturers and bullet weights shot. Best were the Winchester Ballistic Silver Tip 150gr at 2689 fps and 2409 ft/lb energy achieving groups of 0.75” at 100 yards.
I set up a variety of Tom’s Targets steel targets, static crow and rabbit plus a Roe Buck reactive out to 300 yards. The S20 repeatedly achieved some impressive hits and groups with ease. I did take the stock off and on, exchanging the Hunter stock and then back to the Precision, but because that scope was still attached to the action, I had minimal zero change of less than MOA. Very impressive.
Changing the fore-end is a bit more involved – taking it off the chassis without losing the screws and magazine retaining catch does require close attention! The adjustment in the stock is particular appreciated, not only to achieve a comfortable hold but also to ensure you create the correct angle for a particular discipline/application. Length of pull adjustment and cheekpiece height all helps maintain a consistent hold so crucial for good accuracy as well as helps reduce flinch due to better controlled recoil.
Out in in the field, both the Hunter and Precision configurations were equally good. I loved the one-piece Sako scope mount and rail: it offers total peace of mind and the Tungsten Cerakote finish is subdued, hunter friendly and totally weatherproof.
Armed with some Sako 123gr game heads, Winchester B Silver Tips and a reload of 47.0gr of Swiss RS50 powder under a Hornady SST 150gr bullet, I managed to blood the S20 with two nice younger roe bucks, both coming to a call in the rut plus some troublesome crows and longer-range rabbits.
Incredible, in a word, and that’s a totally independent and honest opinion. It is consistently accurate straight out of the box, it has excellent balance and a very smooth bolt operation. The hybrid modular design provides superb ergonomics and take-down potential, exchange and storage features.
Best of all is the price – considering what you get, plus ongoing potential for change and upgrading, the S20 is a total bargain.
FACTORY LOAD PERFORMANCE IN SAKO S20 PRECISION
MAKE - WEIGHT (grains) - VELOCITY (fps) - ENERGY (Ft/lbs) - ACCURACY @ 100 yards
Sako Game Head - 123gr - 2944 - 2368 - 1.00
Winchester Ballistic Silver Tip - 150gr - 2689 - 2409 - 0.75
Hornady Whitetail Interlock - 150gr - 2783 - 2580 - 1.00
Hornady SST - 150gr - 2898 - 2798 - 0.95
Sako Super Hammer Head - 150gr - 2777 - 2569
Geco Express - 165gr - 2584 - 2447 - 1.20
Browning BXC - 168gr - 2524 - 2377 - 1.10
Barnes TSX Vortex - 168gr - 2601 - 2524 - 1.25
Remington MatchKing - 168gr - 2654 - 2628 - 1.15
Norma Tip Strike - 170gr - 2579 - 2511 - 0.95
Winchester Subsonic - 185gr - 1049 - 452 - 0.85
(I would be happy with any of these loads only changing between the weights to suit the differing deer species encountered)
RELOAD PERFORMANCE IN SAKO S20 PRECISION (all used Federal Match primers)
BULLET - WEIGHT (grains) - LOAD - VELOCITY (fps) - ENERGY (ft/lbs) - ACCURACY @ 100 yards
Hornady V-Max - 110gr - 53.0gr of CFE 223 powder - 3116 - 2371 - 0.90
54.0gr - 3184 - 2475 - 1.0
54.5gr - 3218 - 2529 - 0.75
Nosler Ballistic Tip - 125gr - 41.0gr of Reloder RL10x - 2923 - 2371 - 0.75
42.0gr - 2984 - 2471 - 0.45
42.5gr - 3014 - 2522 - 0.85
Hornady SST - 150gr - 47.0gr of Swiss RS50 - 2707 - 2440 - 0.65
48.0gr - 2768 - 2552 - 0.85
Sierra Game King - 150r - 47.0gr of Reloder RL15 - 2728 - 2478 - 0.90
48.0gr - 2786 - 2586 - 0.75
48.5gr - 2816 - 2640 - 0.55
Berger VLD Hunting - 155gr - 44.0gr of Vit N140 - 2648 - 2414 - 0.85
45.0gr - 2704 - 2516 - 0.85
HOT 45.5gr - 2731 - 2567 - 1.0
Hornady ELD-M - 168gr - 45.5gr of Swiss RS52 - 2602 - 2526 - 0.65
46.0gr - 2631 - 2582 - 0.80
46.5gr - 2660 - 2639 - 1.25
SAKO S20 PRECISION - TECH SPECS
Make/model: Sako Ltd S20 Precision
Type: Bolt Action
Overall: Length 39.85 inch
Barrel length: 20 inch, 5/8th 24 UNEF muzzle thread
Length of Pull: 14.25 inch (adjustable)
Weight: 3.26kg(rifle only)
Finish: Tungsten Cerakote
Calibre: .308 Win
Stock: Black synthetic quick detachable take down facility. (thumbhole Hunter version available)
Magazine: detachable, 5 and 10 optional
Scope mounts: Integral Picatinny rail and Sako one-piece scope mount and changeable scope rings available.
Trigger: Single stage, adjustable
Product: Sako S20 Precision
Supplier: GMK Ltd
Tel: 01489 579999
Price: RRT Precision £2,185 (£1,955 Hunter)
Toms Targets: 07989 072693 - Steel targets
Norman Clark: 01788 579651- Reloading Supplies