To resolve the challenges of wireline coring drilling in hard, intact, and low-abrasion “slippage” formations, where excessive wear resistance of the bit matrix hinders diamond self-sharpening and reduces penetration efficiency, this paper proposes and validates an in-hole gravel injection method. By analyzing the bit structure and the causes of “slippage,” the study identifies the imbalance between matrix wear rate and diamond consumption as the core issue. The gravel injection method involves introducing high-hardness, angular gravel materials into the bottomhole to artificially accelerate matrix wear, thereby promoting diamond exposure and restoring cutting capability. Results demonstrate that this method significantly enhances bit self-sharpening performance, achieving a single-round-trip penetration of 2–3 m and a cumulative bit life of 45 m. It resolves “slippage” without requiring drill string tripping, reduces labor intensity, fully leverages the advantages of wireline coring technology, and provides an efficient, low-cost technical reference for drilling in similar formations.