RAW Rapid HM1000X Hammer Spring

[MikeAllen]

What range of velocities should I expect from hammer spring adjustment on the R.A.W. HM1000X .25 caliber rifle? On mine, turning the hammer spring 2-3 full rotations in or out has almost no effect on velocity. I know it is supposed to be a fine adjustment, but I'm seeing only 1-2 fps difference.

 

[Stubbers]

What range of velocities should I expect from hammer spring adjustment on the R.A.W. HM1000X .25 caliber rifle? On mine, turning the hammer spring 2-3 full rotations in or out has almost no effect on velocity. I know it is supposed to be a fine adjustment, but I'm seeing only 1-2 fps difference.

Sounds like another over-sprung pcp, what regulator setting are you running?

Best options are to either up the regulator, or, order a new spring with slightly less lb/in rating.

This calculator will allow you to determine the current springs rating, if you're willing to tear down and measuring with calipers.

Spring Rate Calculator

-Matt

 

[MikeAllen]

Sounds like another over-sprung pcp, what regulator setting are you running?

Best options are to either up the regulator, or, order a new spring with slightly less lb/in rating.

This calculator will allow you to determine the current springs rating, if you're willing to tear down and measuring with calipers.

Spring Rate Calculator

-Matt

Thanks Matt - I’ve also engaged Air Worx in troubleshooting.

 

[Stubbers]

Thanks Matt - I’ve also entrapped Air Worx in troubleshooting.

Good deal. If you do go the route of seeking a weaker spring, make sure it has similar dimensions (OD, ID) and equal length, primarily only reducing the lb/in rating.

-Matt

 

[Raydee38]

I swapped out the RAW reg on my .22 with a Huma regulator and to get the desired velocity I wanted I had to turn the Huma reg down quite a bit (110psi). After that my hammer spring barely makes any changes also.

 

[Stubbers]

I swapped out the RAW reg on my .22 with a Huma regulator and to get the desired velocity I wanted I had to turn the Huma reg down quite a bit (110psi). After that my hammer spring barely makes any changes also.

If you're keen on tearing down and measuring the spring dimensions to figure out the rating.

Compression Spring Calculator

compression spring calculator, compression spring design, compression spring calculation, compression spring calculations, calculate spring constant, spring design, calculating spring constant

www.planetspring.com

From there you can source a spring similar in dimensions with a smaller wire od, and check that calculator again to make sure its not TOO weak. Ideally only a 1-2 less lb/in spring.

There are other ways to skin the cat but the above allows you to return to the stock spring if you wish.

-Matt

 

[Raydee38]

If you're keen on tearing down and measuring the spring dimensions to figure out the rating.

Compression Spring Calculator

compression spring calculator, compression spring design, compression spring calculation, compression spring calculations, calculate spring constant, spring design, calculating spring constant

www.planetspring.com

From there you can source a spring similar in dimensions with a smaller wire od, and check that calculator again to make sure its not TOO weak. Ideally only a 1-2 less lb/in spring.

There are other ways to skin the cat but the above allows you to return to the stock spring if you wish.

-Matt

I will def look into that. I wonder if the RAW .25 comes with a heavier spring than the .22 does. I did switch the barrel and probe on my RAW .25 for a .22 but never messed with the hammer spring.

 

[corny]

While it’s difficult to know what going on now.

But when I ordered springs from Martin a couple years ago, they were specificly marked that they were intentionally long and to be clipped during the tune.
And to be honest I never found the hammer adjuster to do much of anything on a raw.my thought was its simply to fine tune for the sweet spot.

In order to tune up or down. I had to adjust the reg, and either make a hammer spring spacer or clip the spring itself.

I guess what I’m trying to say, they really aren’t setup to srsly mess with fps.
Your best bet is recording where you are now, get duplicates of stuff to mess with the tune.

 

[Stubbers]

While it’s difficult to know what going on now.

But when I ordered springs from Martin a couple years ago, they were specificly marked that they were intentionally long and to be clipped during the tune.
And to be honest I never found the hammer adjuster to do much of anything on a raw.my thought was its simply to fine tune for the sweet spot.

In order to tune up or down. I had to adjust the reg, and either make a hammer spring spacer or clip the spring itself.

I guess what I’m trying to say, they really aren’t setup to srsly mess with fps.
Your best bet is recording where you are now, get duplicates of stuff to mess with the tune.

If the HST adjuster makes reasonable changes in preload, it SHOULD make reasonable changes to fps...having the same spring cut down doesn't necessarily help, you need a spring with a lower lb/in rating...that is unless, it is a Cothran style valve that just blows open, then a HST is useless, but I doubt this valve is such a style.

-Matt