M1A Adjustable Spindle Valve
Last year I wrote an article about my attempts to suppress a Springfield M1A Scout Squad with an 18” barrel. I detailed how I modified the factory gas plug with gas ports and an adjustment screw to set the gas regulation. After a couple of iterations, I had a usable product that ultimately did work for suppressing the rifle, but I didn’t love the results. While the gas was adjustable, the rifle was still extremely gassy even on its lowest setting. Likely bigger gas vents would have solved that issue, but a new (and much better) solution presented itself shortly thereafter.
Enter the folks from Shooting Sight, who make an adjustable spindle valve for M1A/M14 rifles. They were kind enough to send me one to test out on my rifle, and I’ve got to admit their product works great and is much easier for the home user to install than my solution.
This spindle valve is a drop in replacement for the factory part. However, it has a screw for regulating gas as well as two different gas settings. The two gas settings are a huge advantage over my modified gas plug because it allows the shooter to select between suppressed and unsuppressed gas systems by rotating the valve ¼ turn.
While testing out this spindle valve, the first thing I tried was opening the valve to its most closed position. Firing the rifle with the gas effectively “off”, it obviously didn’t eject the case or even move the bolt. This demonstrated the range of adjustment possible with this valve. With the modified gas plug, the rifle would usually still partially eject the spent brass which tells me that it wasn’t venting enough gas.
After that test, I incrementally increased the gas flow through the valve until the rifle cycled reliably with my suppressor installed. This setting will vary based on ammo selection, but is easy to change in the future. A simple lock nut holds the adjustment screw in place. With the gas tuned to my ammunition and suppressor, the rifle cycled great and was significantly less gassy than with the modified gas plug.
As mentioned earlier, this spindle valve has two settings which is a very nice advantage. The first setting is adjustable, which is the one tuned/set for suppressor use. The second setting is close to the factory gas setting and shouldn’t require any adjustments. This allows shooters to swap between suppressed and unsuppressed shooting without losing their spindle valve settings. Swapping between the two settings is only a matter of rotating the gas valve ¼ turn to either horizontal or vertical, depending on the setting desired.
If you’re looking to suppress your M1A rifle, head over to Shooting Sight’s website to find these adjustable spindle valves. Probably one of the easiest ways to regulate your rifle’s gas settings. If you have any experience with these kits or have questions about suppressing your rifle, drop a comment below!
Chris W.
www.John1911.com
“Shooting Guns & Having Fun”
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