The S-300PS/PMU Volhov-M6 (SA-10B) can hit the SCUD in theory, as good as the Patriot was able during the first Gulf War...
(any target with the speed of 1200m/s)

... but the S-300PM/PMU1 Volhov-M6M (SA-20A) is designed from scratch to be able to kill it.
(any target with the speed of 2800m/s)

ATBM Capability
Testing of new capabilities for the S-300P and S-300PM continued even after the S-300PM entered service. The most significant testing occurred in the aftermath of Operation DESERT STORM.
Almaz and Fakel engineers had examined the performance of the American PATRIOT missile system during SCUD missile intercepts and found that the PATRIOT was not nearly as effective as was needed to defend a large populated area. Accuracy was not the issue; PATRIOT missiles consistently found their targets. The problem was one of target destruction.
When the PATRIOT missile warheads detonated, they often simply knocked the SCUD off its flight path without destroying the inbound warhead. When defending an isolated facility, this would be sufficient. However, intercepts attempted by Israeli PATRIOT batteries were of particular interest to the Russian engineers. Often times the inbound warheads still landed in populated areas. To be truly effective in an ATBM capacity, a SAM system would have to destroy the warhead in-flight.
Testing of various S-300P variants at both Sary Shagan and Kapustin Yar proved that the system did have the ability to intercept tactical ballistic missiles at various ranges, depending on the missile system employed and the speed of the incoming target. Fakel MKB engineers, however, developed an even more effective solution in the aftermath of DESERT STORM: a special warhead designed to cause the inbound warhead to detonate in-flight.
The first test firing of the modified warhead occurred in August of 1995 at Kapustin Yar. The missile's warhead successfully caused the warhead of the 8K14 target to detonate in the atmosphere. The missile employed a directional warhead, which is roughly analogous to a shaped charge system insofar as it is able to direct the bulk of the explosive force of the warhead towards the target.