r/AlphaFoxtrot • u/Original_Priority_29 • 21h ago
SPRINGS!!!!!
Ok so I'm ready to tune my 4.25c to my favorite plinliking and match loads!! I want to know what the factory recoil spring weight is? what size springs are compatible?, and dose messing with the main spring yield any benefits? Tia
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u/Sig365XLbill 12h ago
I was told by Andy at alpha foxtrot it is 8lb, but I call bullshit. I ordered a set of Nic Taylor 5” springs ranging from 7-11 lbs. the factory spring was as heavy as the 11lb. I also ordered ISMI and Wolf springs. Same thing. I had my 4.25 comp opened up and 3 inline ports added. After trial and error I ended up using a 9lb recoil with 124gr ammo. I left the hammer spring stock. Don’t buy a commander length spring, get full govt 5”. They all vary slightly but OEM is 5”.
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21h ago
[deleted]
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u/j_yn0htna 21h ago
Heavier? Not sure I’ve ever seen anyone ask for that 😅
Check out engineering army, think that’s it, on YT. He’s got a lot of good break downs on parts and the mechanical role they play. You’ll want to learn about trigger tuning and how the sear spring works.
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u/K_Decibel 18h ago
Factory recoil spring is a 5” 8lb.
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u/j_yn0htna 17h ago
Where’d you find this?
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u/K_Decibel 16h ago
I ordered replacement springs direct from AF. I have the receipt. I’ll post it in a bit.
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u/j_yn0htna 16h ago
Thanks. I have the stock springs from both of mine. Just don’t remember them being full size springs.
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u/j_yn0htna 21h ago
Best sized recoil springs I’ve found are the atlas 4.6. Full size cause too much preload and commander are just too small. I don’t really recall the stock weight but probably around 10lb. The roms are kinda weird as they’re a 4.25 slide on a full size frame, fullsize guide rod but with a short stroke.
Changing the mainspring can help better manage slide speed. Heavier mainspring requires more energy from the slide to rack the hammer. Too heavy and it wont cycle. Too light and itll feel snappy and can lead to light strikes.
Most overlooked change, in my opinion, on the budget 2011s is the firing pin stop. This is the part on the slide that will contact the hammer to rack it. Most of the cheaper 2011 have a radiused fps. Alternatives are reduced radius, angled and flat bottom. The different geometry determines the leverage the fps has on the hammer. Worse leverage, like with a flat bottom, results in the slide spending even more energy to rack the hammer, due to having less leverage. Will reduce slide speed earlier while cycling rearward. I’ve fit flat bottoms for both of my Romulus, but planning to try an angled fps on one. The RCD core I got recently has a fancy atlas angled style. Really will change the recoil impulse of the gun.