Reload Change for Heavier Red Dot Sight?

I've been using Terry's Magnus #801 bullets over 4 grains Bullseye for as long as I can remember.  
This is with both steel sight 45's, and with a slide mounted sight (Matchdot II, but now Aimpoint Micro).

I would like to try out an Aimpoint 9000sc which is considerably heavier.
I assume if the gun cycles properly, no changes are required.

If the gun no longer cycles as it should, what change might I need to make in the loading?

If it makes a difference, this is for shooting one handed, at 25 yards.  
The gun feels better (read lighter) with a Micro Aimpoint.
The gun feels like it weighs next to nothing with an Ultradot L/T.
I've never had a 9000 in my hands until yesterday - it makes the gun feel twice as heavy, but also feel twice as "stable".

What weight recoil spring are you using? I run a minimum of a 10 pound spring in my 45's that have 9000sc dots then add powder till they cycle reliably.  I'm at 4.05 WST, 10# variable Wolff spring, .463 crimp and Magnus #801. Your hold can make a difference too.

I can run 3.5 in some of my 45’s with the 9000 on it. Typically you will probably need 3.8-4.0 BE. You will also need a 200 gr bullet or the Summers 180 to make enough pressure to cycle reliably. I use 10# recoil spring.
Jon

Good points, and I don't have an answer.  The gun is a Salyer modified Springfield Armory that I bought one year ago from this forum, but I'm not sure that Dan would remember what spring was in it.  

I can buy this tester when it's back in stock:
https://www.dillonprecision.com/secure-firearms-products-1911-recoil-spring-tester_8_16_25940.html

Or you could just buy a spring for like $10

Yup, buy a new fresh 10# spring from Brownells and you don't have to tinker with a tester that may or may not be accurate.

I like these so I don't have to remember which spring is which if you are experimenting with springs.

https://www.taylor-tactical-supply.com/1911-recoil-springs-p/1911-recoil-spring.htm

I need to re-wire my brain so I think like you guys - my first inclination is always to buy a tool.

Depending on what happens tomorrow, I'll probably place the oder, unless everything works fine, in which case I'd like to know what spring is in the gun now....

I like those color coded springs!  

I still think the idea of a good spring tester kit is a good idea.