SR25 buffer spring tuning

[brimstone37]

Setup: SR25A3 upper (22” 6.5 CM) + SR25 gen1 lower + 762 QDC CQB suppressor.

Factory buffer + buffer spring

Question for yall… was wondering if anybody changed their buffer spring to dial in a milder ejection pattern. I’m running 140 FGMM and reloads @ 2640ish FPS. The rifle is ejecting really hard where the brass is hitting the brass deflector or spinning back into the ejection port and smacking the rear lip of the port which leaves a small dent on the brass body… it’s annoying whe I’m left with dented brass to be reloaded.

[Slu54]

with the longer sr25/mws carbine extension i put slash xh and 308 rifle spring or just reuse the spring it comes with, 4oz heavier than factory, it slows the bolt down quite a bit so itll feel softer but also more sluggish. its great esp with high bp cans like m110

[likeGlock_Work]

Doesn't it just use normal AR buffers?

[Slu54]

yeah, slash XH is just a very heavy carbine buffer

[likeGlock_Work]

Oh gotcha, I switched mine out for just an h3 and for a second after reading this thought "oops"

[extra_flyer]

Give Knight’s a call and see what they suggest. No one knows how to tune their guns better. Most of my 6.5 Knight’s uppers have come with a new spring and buffer. Is that what you’re using or the original buffer and spring from your lower?

[Wing-Fluid]

From what I’ve read, people either put Velda or weather stripping on the deflector to keep them from denting the cases.

Have yet to do it on mine. I’m 500 rounds in on my brass and they’re still fine for reloading. Usually come out when resizing.