****Performing any modifications to your rifle may create an unsafe condition and are not recommended by me****
The ever so slightly longer spring on top is the MCarbo. Adjusted until the screw was a half a thread from falling out the lowest average was 2lbs 10oz.
The Yo Dave spring on the left set as per the instructions for the MCarbo yielded an average of 2lbs 6oz, same setting yielded an average pull of 2lbs 14.8oz with the MCarbo.
So, I thought, I have 2 springs and one gun, let's cut one up and see what happens.
I cut a full round off of the MCarbo, set it as per their instructions, average pull was 2lbs 10oz, backed out until just a half a thread was holding it averaged 2lbs 4oz.
Removed it 2 more times and trimmed a little off the last coil, reinstalled and tested, set per the instructions it yielded 2lbs 5oz with the first trim, second trim was pay dirt, 2lbs 0.1oz average over a ten pull test.
Reassembled and did a vigorous bump/drop test, to the point my buddy thought I was going to bust the stock, 10 bumps and then a pull test, 3 different times and the average pull was 2lbs 0oz, each pull test was exactly the same, which is surprising since they always vary 2-3oz.
So, I don't recommend that you or anyone else cut their spring, but you want as close to a 2 1/2lb trigger pull as possible, the Yo Dave spring is highly recommended.
Just a heads up, they ship Canadian post, you will not receive tracking information, it just shows up about 2 weeks later giver or take, it could have been in the mail box a few days.
If you are confident in your abilities, then you can modify your spring as you see fit, but order 2 of them for safe measure. Start small and trim small each subsequent time, and vigorously bump/drop test your rifle.
A 2lb flush X-Bolt trigger is a thing of beauty, rivaling the Tikka T3x trigger with an Ernie The Gunsmith Varmint spring.
Good luck and be safe!