I have an nsa pin probe and carrier as well as a huma high flow transfer port added to my M3. My 2nd reg is set at about 80psi. When I'm shooting, the hammer spring adjustment seems to have no or only a tiny difference when set all the way up to 16 and adjusted back down to 1. I have tested this over nearly the entire valve adjstment. The valve adjustment will change speed, but the hammer adjustment doesn't. So every time I adjusted the valve I then ran through hammer settings top to bottom. Valve adjustment makes a change, subsequent hammer adjustments do not. I haven't had that system part yet to see just how it works, so I'm at a bit of a loss. Does anyone have some wisdom to share here? Thanks
Tuning m3 hammer spring adjustment doesn't change speed
- Thread starter scoutscope
- Start date
What type of ammo and at what velocity? With only 80 psi on regulator your hammer MIGHT BE opening the valve completely at the lowest setting and all other settings have no further effect. Try reducing the hammer spring compression by adjusting the micro wheel in front of the hammer adjustment wheel.
Upvote 0
Gonna need some more specifics like caliber, pellet weight, barrel length, actual speeds, etc. I assume you mean 80 bar on the second reg. All the valve adjuster does is increase the resistance to open the valve. It's the last thing you should adjust after getting the speeds you're looking for. Open it to the fourth line or a little more and leave it there for now. Use the hammer spring adjustments and second reg pressure to increase speed.
Upvote 0
.25 cal shooting33.95gr jsb. 650-810 fps depending on valve adjustment. I don't really care what speed at the moment. I'm just trying to get normal tuning results. 700mm barrel.
Upvote 0
scoutscope
Patrick
scoutscope, can you tell us where you gun was before the "NSA pin probe" and "Huma TP" was installed. This is critical information.
Patrick
Upvote 0
I think Frostbite was right. You're getting all 80 bar can give you with the lightest hammer strike and the valve adjust is simply reducing speed from there. You need to increase second reg pressure. Probably to something like 120 bar or more, but take it up in 5-10bar increments. You should see speeds start to increase with the power wheel steps.
Upvote 0
FX says that a .25 cal should have a 2nd reg setting of 90-95 bar, go up to at least that to start with.
Upvote 0
I'll try more pressure on second reg tonight, working my way up. I didn't want to start with the recommended pressure for a stock gun as mine gets way more air behind the projectile now. I figured err on the side of caution.
Upvote 0
I think it's more of a timing thing than an air volume thing. The less restricted port allows plenum pressure to 'transfer' to the barrel faster. Sorta like using faster burning powder in a firearm. The ramp up to full pressure behind the pellet happens quicker producing more acceleration earlier in the shot cycle.
But there's no free lunch. A certain amount of pressure is going to drive a certain amount of weight just so fast in the time available while the pellet is still in the barrel.
But there's no free lunch. A certain amount of pressure is going to drive a certain amount of weight just so fast in the time available while the pellet is still in the barrel.
Upvote 0
Your hammer spring is set way to high for the regulator set point. If want to add the ability to adjust your speed you’ll have to back off the fine adjustments of hammer or add to the regulator set point. I find it better to only use the forward valve for fine tuning after you reach you target speed plus 10-15 fps. As it controls the dwell on the valve.
I’d recommend you start by moving the forward valve to the open 4th line, turn your hammer wheel to 1. The bump your reg 3-4 bar and shoot over the cronie.
Slowly walk the regulator and hammer up. adding hammer spring until it stops building speed. Then, Click down one on the hammer and bump up the regulator 3-4 bar. Always run on the up side of the hammer. Working up hammer to regulator. Until you reach your target speed plus 10-15 fps. Staying on up side of the hammer. You’ll know your on the up side of the hammer. if you click up one on the power wheel and speed increases and you click up two with no increase or speed drop on the second click. Finsh up your tune with fine adjustments on the forward valve knob, making 1/8 turns of adjustments shooting 5-6 shoot at each point of adjustment. Remember: there’s a spring in the forward valve that tightens with each adjustment that needs to settle in with every time you touch the knob. This is why 5-6 shoots. This knob adjusts the dwell. Causing speed change and fine tuning of FPS. There is point of dwell that can cause the speed to rise and fall. So expect anything when adjusting the dwell. Look for target speed with the best standard deviation.
Good luck Mont
I’d recommend you start by moving the forward valve to the open 4th line, turn your hammer wheel to 1. The bump your reg 3-4 bar and shoot over the cronie.
Slowly walk the regulator and hammer up. adding hammer spring until it stops building speed. Then, Click down one on the hammer and bump up the regulator 3-4 bar. Always run on the up side of the hammer. Working up hammer to regulator. Until you reach your target speed plus 10-15 fps. Staying on up side of the hammer. You’ll know your on the up side of the hammer. if you click up one on the power wheel and speed increases and you click up two with no increase or speed drop on the second click. Finsh up your tune with fine adjustments on the forward valve knob, making 1/8 turns of adjustments shooting 5-6 shoot at each point of adjustment. Remember: there’s a spring in the forward valve that tightens with each adjustment that needs to settle in with every time you touch the knob. This is why 5-6 shoots. This knob adjusts the dwell. Causing speed change and fine tuning of FPS. There is point of dwell that can cause the speed to rise and fall. So expect anything when adjusting the dwell. Look for target speed with the best standard deviation.
Good luck Mont
Upvote 0
Yep, that's the way I've found works the best to get a 'conservative' and balanced tune that avoids extreme settings on any of the controls.
The only thing I'd add is to start out with the hammer controls set to the circled factory recommended starting points of macro wheel 8 and micro thumbwheel 3. From there only use the macro wheel and reg pressure to find the speed range you want. The valve control and micro wheel are for fine tuning and getting a consistant spread at the end of the tuning process.
Upvote 0
I'm used to more of a Bob's boat tail approach. I'm looking for my desired speed + 5%. Then I back down off the plateau onto the knee looking for smallest deviations between 3% and5% down from the plateau.
Upvote 0
Now back to the topic of the thread. The M3 did not like the low reg pressure, and did indeed tune as expected once the pressure was increase on the second reg. Thanks for the advice airgunners.
Upvote 0
Thanks for getting back to us with a solution. To many times on forums people seek answers and never tell us what the solution to their problem was. Makes that thread pretty much useless to the next guy with similar problem.
Good Shooting
Upvote 0