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kgj1119
06-13-18, 09:16
I know they are set at .460. I have a slr jig but obviously it’s a .450 not a .460. Opinions on does that .01 make that big of a difference or do I just do the one dimple and call it fine


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thehammer69
06-13-18, 09:20
One dimple is fine

GH41
06-13-18, 09:38
Like he said^^^ but it would be easy enough to drill the screw opposite the gas port, mount the block and use the other hole in the block as a guide to spot the other one using the appropriate tap drill.

lysander
06-13-18, 10:40
In 2014 the Army tested some piston conversion kits on standard M4A1 carbines, some of which used set-screw or clamp-on gas blocks. The barrels were not dimpled, or otherwise modified, nor were any adhesives (i.e., Loctite, Rockset, etc) used on the screws, just torqued to the manufacturer's recommended values. After 6000 rounds, half of which were fired full auto, the one thing that is NOT mentioned is any gas block movement, or loose screws.

This tells me that set screws, torqued properly, on a bare barrel is perfectly adequate, any depth of dimple is more than enough, and there more to ensure proper gas port alignment than anything else.

SPRDon
07-01-18, 14:45
Try adcofirearms.com very reasonable,great quality and quick turnaround