G43X Recoil Spring Weight For Milled & Ported Slide

USMCsilver · Nov 14, 2021

Cross-posted in The Armory, but no replies. Figured this part would be better.

I purchased the linked slide for a 43x build: https://zaffiriprecision.com/product/rts-43-43x-zps-p-rmsc/

I will also be using their ported barrel.

I know the OEM spring for the guide rod is 17lbs.

Since the slide is milled, and the weight will be lessened, would it be advised to use a rod with a 15lb. spring, especially since the porting will slightly lessen the gas pressure during recoil? A little weight will be added with a red dot (probably the RMSc).

Probably a silly question, and maybe I'm overthinking it.

Taking into account the fact that I'll be shooting hotter defensive rounds, I'm guessing the 17lb. would probably still be the best way to proceed.

Thanks.

Sent from my SM-G975U using Tapatalk

Sent from my SM-G975U using Tapatalk

cciman · Nov 14, 2021

R&D is now on you.
Until you put the optic on, I would penny guess a heavier weighted spring will be needed for just the lighter slide.

USMCsilver · Nov 14, 2021

But if there is less wight being forced rearwards, and technically less pressure due to the ports, wouldn't a heavier spring, in this scenario, lead to possible short-stroking and FTE/FTF problems?

Sent from my SM-G975U using Tapatalk

sig357fan · Nov 14, 2021

O.K., first question, once assembled, are you sure the weight differs from the stock slide?

USMCsilver · Nov 14, 2021

No clue. Nothing in possession yet.

Sent from my SM-G975U using Tapatalk

Hydra-SHOKz · Nov 14, 2021

I think you'll be fine with the OEM RSA. Best place to start, IMO. It shouldn't be that much lighter than my 43X slide with RMRcc. What RSA were you contemplating over OEM?

USMCsilver · Nov 15, 2021

I can't find the link now...

I think I'll go OEM and go from there.

And thanks, cciman.

Sent from my SM-G975U using Tapatalk

jonathan.harvey786 · 2025-09-26T23:34:10-0400

Built the same setup with a trijicon dual illumination optic….. cycled properly 20% of the time with the prior tungsten rod 17lb spring setup I had prior to barrel porting. The porting is aggressive enough to purge off significant amounts of gas prior typically assisting with blowback force to fully eject the spent casing….seems to come up short on the back slide preventing proper ejection and in turn cycling…. Ordered a heavyweight rod and 15lb spring hoping that fixes inequalities created in the blowback force and ejection reliability…. It is a Glock, if it jams its builder error and/or miscalculation. Hope this helps

G43X Recoil Spring Weight For Milled & Ported Slide

Top Contributors this Month

Recommended Communities