M&P CORE optic getting fouled by chamber hole

[mpproshooter]

I'm noticing gas residue and dirt fouling up the optic on my M&P CORE slide and it appears to be coming from the loaded chamber indicator hole at the base of the barrel.

Anyone else seeing this? Any options on plugging that hole?

[royal barnes]

I get a small amount on both my Shield 4” and Sig x compact. I believe it is coming from the open ejection port and not so much from the loaded chamber indicator. I have never found it to be an issue affecting my sight picture but it is easily removed if it worries you. My normal cleaning routine includes using a Leupold lens cleaner for the optic.

[Saudade]

Not had any issue with my RDS. Some residue on the front sight, from the ports remain but are easily cleaned off.

What kind of ammo are you using?

[SoCalDep]

This is a known issue. Sig is actually making a plate for their 320s that will block the loaded chamber indicator hole. I do wish S&W would simply make a barrel without it, but other than going with an aftermarket barrel there isn’t much that can be done about it. I just keep a lens cloth in my pocket and wipe the optic occasionally.

[Ethang]

interesting..