FX FX DRS - the regulator

Hi guys, can anyone please tell me at what bar the drs comes regulated at. Thinking of tuning it myself, what's your suggestion on setting the regulator pressure and the hammer strength?

Thank you.


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I think it depend on caliber, my Maverick in 600 mm barrel .177 caliber came set to 90 BAR on the regulator.

You can of course guess pressures in relation to where you are set from the factory, and then gauge subsequent shots by the accuracy of them on a target.
But it is a slower approach VS having the ability to see the pressure on a gauge, and not least measure the speed of your shots with a chronograph.

The DRS do not have a indicator for hammer spring preload setting, so you will have to measure this in relation to the end of the rifle with a caliper.

My friend just got a DRS in 4.5 mm with a 700 mm barrel, its pressure is turned up to 120 BAR in order to shoot 13 grain slugs 970 FPS
My similar sized rifle in another brand shoot that speed at 80 BAR, so i am thinking the single little hole transfer port in 4.5 mm DRS rifles is to blame for my friends issues.
I have no idea what it was set to from the factory, it is a second hand rifle.
 
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If you plan on re-tuning your DRS you will need to put a gauge on your plenum.

This is the only way to accurately set your regulator pressure.

As far as hammer spring tension, that will be determined by the regulator pressure, projectile weight and the speed you want that projectile.
I did my drs t without reg gauge, just upping reg and hammer until fully open valve would give me the speed I want plus some and then dialed the hammer back to go 3-4% below vMax. No idea where the reg is sitting right now (but seems like I am falling off at around 100-105b (.22 600mm). Here’s the result (18gr AEA):
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Tuned my 22 as well with out a gauge it ended way higher reg setting than i thought it was shooting 40gr slugs around 930 I was thinking i fell off the reg around 150 bar according to my gauge and accuracy then I put on a plenum gauge I was at 175 bar for reg and it got decent shot count for that like 15 shots basically a mag full and it's like filling a better Marauder tanks are about the same size lol
 
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Thank you guys,
Gun is a 4.5 cal. I have tuned the regulator to 90, and the hammer at full tension. Since I don't have a chrono can't tell at what fps it's shooting. Pretty accurate with 11 grain at 20 meters from 150 bar and downwards. However, the air consumption is not very efficient and count is about 30-40 shots before it reaches the regulated bar.
 
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Thank you guys,
Gun is a 4.5 cal. I have tuned the regulator to 90, and the hammer at full tension. Since I don't have a chrono can't tell at what fps it's shooting. Pretty accurate with 11 grain at 20 meters from 150 bar and downwards. However, the air consumption is not very efficient and count is about 30-40 shots before it reaches the regulated bar.
You’ll need a chrony to tune it properly but one thing I can tell you without: full hammer spring at 90b is waaaaaay too much hammer, you’re waisting air and are over hitting your valve. You have to dial the hammer way back.
 
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Same on my friends 700 mm DRS, it too ( 120 BAR ) need near full hammer to push a 13 gr slug to 970 fps, the second i go back on the hammer speed drop, and if i lover reg pressure to say 100, well no matter the amount of hammer i can not get up to 970fps

i have heard from Huma today and they will be making a dual transfer port for the 4.5 mm DRS, and i think that is very much needed.

But yes it do sound like my friends DRS is wasting air, but i cant seem to adjust around that and get the speeds i want.
A heavier hammer might also be warranted here.

Again in .177 / 4.5 mm i feel these rifles are just a after thought of brands.

150 bar is a lot of pressure for 10 grain pellets or slugs for that matter, that is the pressure i shoot 24 grain slugs in my 700 mm Two and knocking on 1000 FPS

The 4.5 mm DRS for damn sure have some issues.
 
Same on my friends 700 mm DRS, it too ( 120 BAR ) need near full hammer to push a 13 gr slug to 970 fps, the second i go back on the hammer speed drop, and if i lover reg pressure to say 100, well no matter the amount of hammer i can not get up to 970fps

i have heard from Huma today and they will be making a dual transfer port for the 4.5 mm DRS, and i think that is very much needed.

But yes it do sound like my friends DRS is wasting air, but i cant seem to adjust around that and get the speeds i want.
A heavier hammer might also be warranted here.

Again in .177 / 4.5 mm i feel these rifles are just a after thought of brands.

150 bar is a lot of pressure for 10 grain pellets or slugs for that matter, that is the pressure i shoot 24 grain slugs in my 700 mm Two and knocking on 1000 FPS

The 4.5 mm DRS for damn sure have some issues.
I’d be surprised if the stock hammer is valve locked beyond 120b given what some people do to their DRS… I’d up the reg beyond 120b and try with less hammer to hopefully reduce dwell and increase efficiency. Sounds odd but may do the trick and give you a shorter but stronger burst of air.
 
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I have thought of that, and might well try it, just seem silly to me, fortunately we do shoot tethered to big bottles byt my friewnd only have a 12 L 200 BAR one, so just 50 BAR over a 150 BAR reg setting.

But mind you my friends M30 snowpeaks also run at a very high reg pressure, i assume to be able to push enough thru the little 3 mm transfer port.
But those in turn do not sound like they are wasting air, though a bit harder to judge as they are not fitted with a after market moderator so loud VS my two or friends new DRS.

Going shooting again tomorrow + Wednesday, but i will not be home before Thursday, will make a sound recording of my Two and friends DRS.
Probably also dial a bit more on the DRS CUZ it is messing with my head the way it behave.

In my two i shoot 10 grain pellets at their very upper speed levels, with the minimum 56 BAR the Huma regulator on it can do, so mid 900 FPS speeds
Still fairly accurate though well at least out to 55 M

PS: not sure of fit, but i will also be bringing some hammer weights and springs to my friends place / range tomorrow.
 
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Same on my friends 700 mm DRS, it too ( 120 BAR ) need near full hammer to push a 13 gr slug to 970 fps, the second i go back on the hammer speed drop, and if i lover reg pressure to say 100, well no matter the amount of hammer i can not get up to 970fps

i have heard from Huma today and they will be making a dual transfer port for the 4.5 mm DRS, and i think that is very much needed.

But yes it do sound like my friends DRS is wasting air, but i cant seem to adjust around that and get the speeds i want.
A heavier hammer might also be warranted here.

Again in .177 / 4.5 mm i feel these rifles are just a after thought of brands.

150 bar is a lot of pressure for 10 grain pellets or slugs for that matter, that is the pressure i shoot 24 grain slugs in my 700 mm Two and knocking on 1000 FPS

The 4.5 mm DRS for damn sure have some issues.

FX must have changed something on the DRS tactical. It can make 40 fpe in .177 with a 600 mm barrel . That would push a 13gr pellet at 1177 fps .

My Maverick in .22 makes 47 fpe power at 110 bar and gives me an excellent shot count because of the large plenum and design. One of the reasons I'm keeping it .
 
My 600 mm .177 Maverick that also came with a little hole transfer port, where all other calibers came with both options, as i recall with that i was also able to get things up to speed even if it was a SUB12 rifle i got when ordering a FAC ( sub 12 is not a thing,,,,, yet, on the Danish market )
Adding dual port + pin probe + 700 mm barrel and i had no problem getting 13 gr slugs up to a 970 FPS speed even with just 70 BAR on the regulator.
But it did like it better if i hit them with 90 BAR for the same speed.

I did read / hear about some changes made for the DRST

The DRS have a angled valve housing, i am wondering could it be turned in a unfavorable way, CUZ i dont recall seeing anything that " lock " the valve housing in the correct orientation.