KNS Bolt catch retaining pin.

[AAMP84]

Anybody use one of these? I don't mind installing the regular roll pins, but if this holds up I'd be interested in using it on an upcoming build. Not sure how I feel about the whole thing relying on spring pressure and a c-clip to stay in place. Opinions?

[3 AE]

I have no idea if it's worth it. At least they're including three circlips with the pin. You'll either lose or mangle the first one on the first installation attempt. You'll get the second one in just right on the next try, and the third one will be the spare! Anyone who has ever had to deal with the dustcover pin circlip knows what I'm talking about. :D

[Duffy]

If the whole concept evolves around cosmetics, or fear of marring and impacting cosmetics of the firearm, then I am disappointed to see the fashion market has come to this. If it does something better than a roll pin, then I'm all ears. I'd simply improve it by using coil pin (much stronger), but a roll pin isn't known to be a point of failure, it's the bolt catch itself that can snap in two, so I never bothered to use anything but roll pins.

[vicious_cb]

If the whole concept evolves around cosmetics, or fear of marring and impacting cosmetics of the firearm, then I am disappointed to see the fashion market has come to this. If it does something better than a roll pin, then I'm all ears. I'd simply improve it by using coil pin (much stronger), but a roll pin isn't known to be a point of failure, it's the bolt catch itself that can snap in two, so I never bothered to use anything but roll pins.

Yep, its a terrible design philosophy. Not only did they increase complexity by adding an extra part. They also introduced the e-clip to recoil forces by making it parallel to the bore. How often would the e-clip fail? I dont know, but they do fail. I once had an retaining e-clip sheer on my reloading press and hit me in the eye.

Roger, Im curious if improved AR specific pins and fasteners ect could have a market. Ive been looking for stainless steel coil pins/spiral pins in AR diameters for a while and I dont want to have to buy like 2000 of them at a time. The stock roll pins rust easily and can peen out when driving them in but they seem to work pretty well. Going to SS coil or spiral pins seems like a simple way to make the AR more bombproof without any negatives especially in the bolt catch and charging handle rolls pins. Any chance you can offer a kit of some sorts?

[Duffy]

We would, only if the additional cost is justified. Cost and strength may be correspondingly linear, but in terms of what this extra strength buys you, it's not so clear. cut. The bolt catch pin is one good example. A coil pin is stronger, but the extra strength may be wasted in that application. Of course if given a choice, if cost were equal, I'd always go for the stronger candidate. I've seen broken bolt catches, but not broken bolt catch roll pin yet.

And then there's the case of cotter pin vs. solid firing pin retaining pin. A simple cotter pin is easier to make and cost far less, and it does as well a job as a correctly made solid pin that's is far more expensive.

Many of the 1955 original design, and 1970s and 1980s era changes are sound and saw little change throughout the years, and for good reason. Change doesn't imply change for the better, sometimes change does the opposite (2008 to 2016, Hope and Change comes to mind), I wish more manufacturers would recognize this. A good way to generally tell is whether Colt, FN or KAC either invented, or adopted something new. Weapons that go to war don't have time for fashion bits.