AR: sluggish safety selector

dyl · January 18, 2020, 01:35 PM

What contributes to a sluggish safety selector on an AR?

I assembled an AR pistol. At first the "discount" lower parts kit I used had visibly shallow angles for the safety selector, leading to a mushy feel on activation/deactivation. I replaced the detents and safety switch with leftovers from a CMMG branded kit and while it is a bit crisper when the selector arrives at the actual destinations, it often loses momentum partway and stops in between safe and fire. I have oiled it. My other assembled AR's don't do this, with parts kits from Rock River Arms and PSA.

My guesses are: Weak spring --> weak detent. Rough channel for the detent. Hole in grip drilled too deep --> weak spring pressure. Angles on Safety or detent not steep enough --> weak detent.

Kind of like a pocket knife detent on a frame lock/liner lock.

Am I missing anything? I could try another spring (it looked fine though..), another safety, or fill in the hole in the grip a little bit with something. At first, I was going to ignore this but it's annoying now.

Scorch · January 18, 2020, 03:04 PM

If the safety selector is cast, it could be out of round or not straight. It could be dragging on the tail of the trigger assembly. Weak detent springs make the safety flop around like a loose wing nut.

dyl · January 18, 2020, 05:30 PM

Good thought, hadn’t thought of it. The discount selector definitely was cast, a nice line heading up the center. The other, I’ll have to take some calipers to check for roundness. Thanks!

January 18, 2020, 01:35 PM	#1
dyl Senior Member Join Date: October 31, 2009 Location: Ohio Posts: 1,310	AR: sluggish safety selector What contributes to a sluggish safety selector on an AR? I assembled an AR pistol. At first the "discount" lower parts kit I used had visibly shallow angles for the safety selector, leading to a mushy feel on activation/deactivation. I replaced the detents and safety switch with leftovers from a CMMG branded kit and while it is a bit crisper when the selector arrives at the actual destinations, it often loses momentum partway and stops in between safe and fire. I have oiled it. My other assembled AR's don't do this, with parts kits from Rock River Arms and PSA. My guesses are: Weak spring --> weak detent. Rough channel for the detent. Hole in grip drilled too deep --> weak spring pressure. Angles on Safety or detent not steep enough --> weak detent. Kind of like a pocket knife detent on a frame lock/liner lock. Am I missing anything? I could try another spring (it looked fine though..), another safety, or fill in the hole in the grip a little bit with something. At first, I was going to ignore this but it's annoying now.

January 18, 2020, 03:04 PM	#2
Scorch Senior Member Join Date: February 13, 2006 Location: Washington state Posts: 15,248	If the safety selector is cast, it could be out of round or not straight. It could be dragging on the tail of the trigger assembly. Weak detent springs make the safety flop around like a loose wing nut. __________________ Never try to educate someone who resists knowledge at all costs. But what do I know? Summit Arms Services

January 18, 2020, 05:30 PM	#3
dyl Senior Member Join Date: October 31, 2009 Location: Ohio Posts: 1,310	Good thought, hadn’t thought of it. The discount selector definitely was cast, a nice line heading up the center. The other, I’ll have to take some calipers to check for roundness. Thanks!