Royale 500 Regulated Pressure Gauge Project

I took on a little project and thought I’d share if with you folks. The more I get into PCPs the more I want to know. Knowing your regulated pressure is a key to performance and accuracy. Finding out what that pressure is can be a pain if you don’t own a gun with this secondary gauge. With the Royale’s finding this pressure (my way) involved removing the gun from the stock, bleeding off the receiver, removing the stock bolt stud, screwing in a special adapter, hooking up a gauge, pressurizing the receiver again and reading that pressure…finally.

Well I got tired of this method and decided to add and on board regulated gauge.

How I did it….
First I made sure that where I wanted to add the gauge would get me in behind the regulator without screwing something up in the process.

Next I CAREFULLY and as precisely as possible measured and marked the location with a pointed awl, carefully mounted the receiver with the action in it in a vise, got everything leveled up and centered, said a good long prayer and drilled a small hole through the stock and just touching the receiver.

Next, I pulled the stock off the receiver and was pleasantly surprised to find that my drill bit hit the very center of the receiver.
Almost forgot to explain how I bored the hole through the stock. I used a 1″ Forsterner wood bit and followed up with sandpaper wrapped around a 3/8″ slotted to enlarge the hole large enough to accommodate the gauge.

Next I re-positioned the receiver with all the internal components removed back into the cushioned vise and drilled a 1/8″ pilot hole through the receiver into the plenum space. After drilling the pilot hole I drill that hole out to 11/32″. That’s the recommended bit size the 1/8X28 BSPP tap. I then chucked up a BSPT (tapered) tap into the drill press and started a few threads by rotating the chuck by hand. Keeping the tap in the drill press ensured that the hole would be straight. I then switched over to the BSPP tap and finished tapping the hole by hand to the depth I thought appropriate.

It actually tapped pretty easy with a new tap in use. At this point I machined a small delrin spacer/washer to set down in the bottom of the hole for my gauge to seal against. I ended adding a O-ring in between the gauge and the delrin spacer.

The gauge I added wasn’t the easiest to read for an accurate pressure reading so I’m in the process of ordering another FX gauge that is incremented in 10bar divisions. Once I get it in I’ll try to get the gauges facing the same direction for a cleaner appearance.
Hope ya’ll enjoy.
Jimmy

I took on a little project and thought I'd share if with you folks. The more I get into PCPs the more I want to know. Knowing your regulated pressure is a key to performance and accuracy. Finding out what that pressure is can be a pain if you don't own a gun with this secondary gauge. With the Royale's finding this pressure (my way) involved removing the gun from the stock, bleeding off the receiver, removing the stock bolt stud, screwing in a special adapter, hooking up a gauge, pressurizing the receiver again and reading that pressure...finally. Well I got tired of this method and decided to add and on board regulated gauge. How I did it.... First I made sure that where I wanted to add the gauge would get me in behind the regulator without screwing something up in the process. Next I CAREFULLY and as precisely as possible measured and marked the location with a pointed awl, carefully mounted the receiver with the action in it in a vise, got everything leveled up and centered, said a good long prayer and drilled a small hole through the stock and just touching the receiver. Next, I pulled the stock off the receiver and was pleasantly surprised to find that my drill bit hit the very center of the receiver. Almost forgot to explain how I bored the hole through the stock. I used a 1" Forsterner wood bit and followed up with sandpaper wrapped around a 3/8" slotted to enlarge the hole large enough to accommodate the gauge. Next I re-positioned the receiver with all the internal components removed back into the cushioned vise and drilled a 1/8" pilot hole through the receiver into the plenum space. After drilling the pilot hole I drill that hole out to 11/32". That's the recommended bit size the 1/8X28 BSPP tap. I then chucked up a BSPT (tapered) tap into the drill press and started a few threads by rotating the chuck by hand. Keeping the tap in the drill press ensured that the hole would be straight. I then switched over to the BSPP tap and finished tapping the hole by hand to the depth I thought appropriate. It actually tapped pretty easy with a new tap in use. At this point I machined a small delrin spacer/washer to set down in the bottom of the hole for my gauge to seal against. I ended adding a O-ring in between the gauge and the delrin spacer. The gauge I added wasn't the easiest to read for an accurate pressure reading so I'm in the process of ordering another FX gauge that is incremented in 10bar divisions. Once I get it in I'll try to get the gauges facing the same direction for a cleaner appearance. Hope ya'll enjoy. Jimmy