[2] The TRG-62 A1 was added to the product range as the third and largest iteration, designed to fire the even more powerful and dimensionally larger .375 CheyTac (9.5×77mm) cartridge.

Variable telescopic sights can be used if the operator wants more flexibility to shoot at varying ranges, or when a wide field of view is required.

It was designed as a user configurable multi calibre modular system responding to evolving market demands and does not share its receiver and other technical features with the rest of the (single caliber) TRG line.

[5] Even though the TRG-21 obtained its origins from the successful Sako TR-6 target rifle and 1984–1986 development work for the hardly produced Valmet Sniper M86 rifle by the former Finnish state firearms company Valmet which merged with Sako, the 4.7 kg (10 lb 6 oz) TRG-21 was designed as a result of a thorough study of sniper requirements.

A more hunting oriented variation of the TRG was introduced in 1992 as the TRG-S M995 and TRG-S M995 Magnum, which both use the same scaled up magnum action and bolt (different bolt handle) as the TRG-41 with the exception that the receiver is open at the top with an integral Sako-type wedged dovetail rail rather than possessing a cartridge ejection port on the right side and a parallel 17 mm (0.67 in) integral dovetail rail as found with the TRG-41.

Four different sized detachable box magazines and three different bolt bodies were used to accommodate the dimensionally different rifle cartridges offered.

Sako planned to produce a short action TRG-S M975 designed for a maximum cartridge length of 75 mm (2.95 in), that would have been based on the TRG-21.

Some TRG accessories like the muzzle brake and bipod (that lets the rifle swivel or "hang" near its bore axis offering a more stable shooting position with large and heavy aiming optics mounted) were also improved.

[9] Around 2011 an American Sako vendor commissioned a special limited production run of TRG-22 sniper rifles chambered in .260 Remington cartridge and started offering them as of May 2011.

The upgrades consist of mounting improved recoil pads to reduce felt recoil, a newly constructed bolt release and a new fully adjustable two-stage trigger mechanism that features a new more ergonomic ambidextrous safety lever, and a trigger guard milled from aluminium for more positive magazine attachment.

The TRG A1 models have a Sako TRG M10 Sniper Weapon System alike stock, featuring an aluminium middle chassis frame, side-folding quick adjustable buttstock, and a fore-end with the M-LOK rail interface system that allows for direct accessory attachment onto "negative space" (hollow slot) mounting points.

[12] The chassis frame is offered in Tungsten Gray, Olive Drab Green, Graphite Black and Coyote BrownCerakote finishes.

The bolt handle is the appropriate length and sports a large synthetic bulbous knob that provides a firm, positive grip.

On top of the receiver a 17 mm (0.67 in) integral dovetail rail with shape connection drillings for one or more recoil lugs provides for fixing mounting components to accommodate different types of optical or electro-optical sights.

[22] The receiver's large bedding surface is mated to an aluminium alloy-bedding block by three screws for maximum stability.

[22] The detachable box magazine is based upon centre feeding for maximum reliability as well as precise positioning of the cartridge into the chamber.

For the .338 Lapua Magnum chambering a non-traditional 305 mm (1 in 12 inch) or 36.4 calibres right-hand twist rate was selected to optimise the rifle for firing 16.2 gram (250 grain) .338-calibre very-low-drag bullets.

The polyurethane buttstock with its pistol grip and integrated aluminium skeleton to add strength, is designed for right- and left-handed shooters.

The rear of the buttstock possesses a series of spacer and angle plates to regulate the length of pull and curvature adjustments that can be tailored for the individual shooter.

[22]The stock features two steel sling swivel attachment sockets positioned at the right and left rear sides of the buttstock.

This forward sling attachment point can be (re)positioned along the length of the rail for right- or left-handed use and is fixed with a screw.

Sako TRG folding stock rifles are supplied with a Picatinny rail for mounting aiming optics.

Several versions of TRG-specific bipods were produced that all lock into an attachment point in the aluminium bedding block at the end of the forestock.

It has a narrower leg angle due to complaints that the previous version interfered with some night vision systems mounted forward of the telescopic sight.

Further versions of accessories are the ITRS tri-rail NV attachment point with an optional extended aluminium bedding block.

[36] It was designed as a user configurable modular system and does not share its receiver and other technical features with the preceding models in the Sako TRG line.

The TRG M10 has a side-folding and fully adjustable buttstock, featuring an aluminium middle chassis frame, side-folding buttstock, and a fore-end with the M-LOK rail interface system that allows for direct accessory attachment onto "negative space" (hollow slot) mounting points, ambidextrous controls, a manual safety that is located inside the trigger guard which is in front of the trigger, and uniquely designed tactical indicators which helps identify different modular components for different calibres, where every calibre-depending component is specially marked so users can recognise the calibre of each part visually or by touch.

An additional set of Torx keys are stored inside a small detachable polymer forend, which are necessary for full disassembly of the gun.

[36][42] Sako states that the TRG M10 factory acceptance tests with high quality match ammunition has an accuracy of 1 MOA (0.291 mil) for .338 Lapua Magnum and .300 Winchester Magnum chambered models and ⅔ MOA (0.194 mil) for .308 Winchester chambered models.