Anyone familiar with the H&K 417 16inch recce model. A good all rnd versatile platform albeit with some design faults. The bolt houses two ejector posts which are exposed by two open ports on the bolt unit located between the locking lugs. The rifle is designed around a direct impingement system for gas regulation which typically means less fouling in the receiver group. H&K marketed heavily on this however the inclusion of grooves in the chamber to assist with cartridge extraction allows excessive and rapid build up of carbon fouling onto the forward area of the receiver group to include the open ports to the ejector posts. The result is a malfunction typically known as a 'stovepipe' stoppage in as little as 500rnds due to excessive carbon build up on the ejector post and accompanying springs. Anyone familiar with this happening? It is particularly evident during colder temperature as the carbon fouling is less viscous.