According to Steven Zaloga, the IS-2 and Tiger I could knock each other out in normal combat distances below 1000 m. At longer ranges the performance of each respective tank against each other was dependent on the crew and combat situation. The September 1944 issue of the Nachrichtenblatt der Panzertruppen included a report from a Tiger-Kompanie that had knocked out numerous Josef Stalin tanks in a short period:

The Tiger Kompanie was ordered to throw out the enemy who penetrated into a wood, and then continue to advance. About 12:15 hours, together with an Infanterie-Batallion the Tiger Kompanie started to attack. The thick forest caused extremely poor visibility (50 meters), and a narrow trail forced the Tiger-Kompanie to advance in a single row. The Russian infantry fled their positions as soon as the Tigers appeared. The anti-tank guns, which were pulled forward into position by the enemy within three-quarters of an hour after entering the woods, were quickly destroyed in spite of the difficulty of seeing the targets. Some of the anti-tank guns were destroyed by hits and some were rolled over. Numerous undamaged anti-tank guns fell into our hands.

Ausf.E late Tiger with sPz.Abt. 510, 1944 [Via www.tanks-encyclopedia.com]

After the lead Zug of the Tiger Kompanie advanced 2 kilometers through the forest, the Zug leader suddenly noticed knocked-down trees and saw a large muzzle-break (Josef Stalin) directly in front of him. He immediately gave the fire command: "Panzergranate! Cupola sight! Fire!" At the same time he was hit twice by 4.5 cm anti-tank gun shells that robbed him of his sight. In the interim, a second Tiger of the Zug driving through the woods pulled up on line with the Zug leader's Tiger. In spite of poor visibility, the Zug leader started the firefight at a range of 35 meters. In response, the Josef Stalin tank pulled back behind a small hill. In the meantime, the second Tiger had taken the lead and fired three shot at the enemy tank. When the round was fired, the Tiger itself was hit by a 12.2 cm shell on the front below the radio operator's section. Apparently this armor-piercing shell didn't penetrate through because the Tiger was standing at an angle from the target. The enemy tank was knocked out of action by a shot which penetrated the gun. A second Josef Stalin tank attempted to cover the first as it pulled back. During a short firefight, one of these two Tigers hit the second tank under the gun. This round penetrated, immediately setting the enemy tank on fire. The rate of fire of the Josef Stalin tanks was comparatively slow.

The Kompanie commander made the following observations that were derived from their experience in fighting Josef Stalin tanks:

1. When a Tiger appears, most Josef Stalin tanks turn away and attempt to avoid a firefight.
2. In many cases, the Josef Stalin tanks let themselves engage in a firefight only at long range (over 2000 meters) and also only when they themselves are in favorable positions on the edge of a wood, village, or ridgeline.
3. The enemy crews lean toward evacuating their tank immediately after the first shot is fired at them.
4. In all cases the Russian strived to prevent a Josef Stalin tank from falling into our hands and with all means available attempted to tow the tank away or to blow it up.
5. The Josef Stalin can also be knocked out, even if a penetration of the frontal armor can't be achieved at long range. (A different Tiger-Abteilung reported that the front of a Josef Stalin tank can be penetrated by a Tiger only at ranges less than 500 meters.)
6. An attempt should be made to gain the flank or the rear of the Josef Stalin tank and destroy it with concentrated fire.
7. In addition, a firefight with Josef Stalin tanks should not be undertaken in less than Zug strength. Employment of single Tigers means their loss.
8. It has been proven to be useful, after the first hits are registered, to blind the Josef Stalin by firing Sprenggranaten (high explosive shells).

Remarks by the Generalinpekteur der Panzertruppen:

1. These experiences are in accordance with those of other Tiger units and are correct.
2. In regard to point 4 - It would be desirable for the opponent to have observed the same attempt by all of our Tiger crews. "An undestroyed Tiger may never fall into enemy hands!" This principle must be achieved by every crew member by exemplary operational readiness.
3. With regard to points 5 and 6 - At a time when there are 12.2 cm tank guns and 5.7 cm anti-tank guns on the Eastern Front, just like 9.2 anti-tank/anti-aircraft guns on the Western Front and in Italy, the Tiger can no longer disregard the tactical principles that apply to the other types of Panzers. Also, just like other Panzers, a few Tigers can't drive up on a ridgeline to observe the terrain. In just such a situation, three Tigers received direct hits and were destroyed by 12.2 cm shells, resulting in all but two of the crew members being killed. The principles of Panzer tactics - that Panzers should only cross a ridgeline together, rapidly (leaf-frogging by bounds) and under covering fire, or else the Panzers must drive around the height - were definitely not unknown in this Tiger-Abteilung . Statements like "thick fur", "impregnable", and the "security" of the crews of the Tigers, which have become established phrases by other units and also partially within the Panzertruppe , must be wiped out and debunked. Instead, it is especially important for Tiger units to pay direct attention to the general combat principles applicable for tank-versus-tank combat.
4. In regard to Point 7 - This statement is correct; however, three Tigers should not flee from five Josef Stalin tanks only because they can't start the firefight at full Zug strength. Cases will also occur which an entire Zug isn't always available. Many times tank-versus-tank combat will be decided, not by the number of tanks, but much more by superior tactics.
5. In regard to Point 8 - In connection with this it may be stated that the Josef Stalin tanks not only can be penetrated from the flanks and rear by Tigers and Panthers but also by the Pz.Kpfw.IV and the Sturmgeschütze.

A Tiger positioned in a camouflaged position for an ambush, in Russia [Via www.tanks-encyclopedia.com - credits: Bundesarchiv]

From Russian side: Tiger as an Adversary of the JS-2 by Valeri Potapov (The Russian Battlefield)

Compared with the Tiger, the JS-2 was slightly better protected even though it was ten tons lighter.. The 88 mm and 122 mm guns had more or less the same AP ability, but again, German gun had less HE ability. Both tanks could penetrate each other's frontal armor from ~1000 metres. At greater distances success highly depended on experience of the crew and battle conditions.

A partially camouflaged IS-2 model 1944 from an unknown Guards Heavy Tank Regiment, late 1944 [Via www.tanks-encyclopedia.com]

The JS-2 had thicker armor, thus it had a better chance at distances over 1500 metres. On the other hand, the Tiger had better optics and thus had a better chance of hitting the JS-2. The main drawback of the Tiger was the slow angular velocity of the turret. However, the Tiger had an excellent length/width ratio (almost 1:1) which made it extremely maneuverable. And if the Tiger could not traverse its turret fast enough, the whole tank could swivel to bring the gun to bear.

Projectiles and charges of the separate-loading ammunition of the A-19/D-25T 122mm gun. Left to right: cartridge case, high-explosive/fragmentation shell OF-471, armor-piercing tracer shell BR-471, armor-piercing ballistic capped shell BR-471B. All shells are shown from two sides [Via en.wikipedia.org]