Gas Block / Piston Upper - Interesting TI
Had an upper in the shop this past weekend - piston upper (Osprey Defence) that had run flawlessly for a few thousand rounds. The rifle had started to short stroke and was FTE. Inspection revealed that the gas block had moved forward - it was an aluminum clamp on unit. I decided to remove the FH & the gas block to clean and inspect everything. I appears that the pounding from the piston assembly pushed the block forward to partially restrict the port - the hot gas combined with the port pressure to completely melt / erode the area around the port. There was no damage to the bbl.
The gas block is being replaced by a steel unit that will be either pinned or double set screwed into recesses in the bbl.
Pretty strong evidence that there is some serious pounding in effect when the bolt / carrier go back into battery.
On top of that - it also highlights the need for quality components - the aluminum gas block is clearly a low budget piece and I wonder what type of aluminum it is made from - definitely not a 6000 or 7000 series.
Pic attached below.
Gas Block A.jpg
Last edited by opsoff1; 05-04-15 at 11:04.
opsoff
"I'd rather go down the river with seven studs than with a hundred shitheads"- Colonel Charlie Beckwith
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