Stumped - please help ID this screw

[AlBeight]

While walking barefoot around my gun bench this afternoon I stepped on this rogue screw on the floor under the table. It is a tiny conical screw, with a 3/32” hex head (wrench inserted in pic). It appears to be a set screw of some kind, and for the life of me I cannot figure out where it belongs or came from. Does this look familiar to anyone? I checked every rifle I’ve had out in the last 6 months, all hunting or long range rifles (haven’t had any of my AR’s or handguns on this table in a long while), and there’s nothing resembling it or any open holes for it. The only “gunsmithing” I’ve done in this time frame is I’ve replaced 2 scopes, installed 2 new others, and installed 3 new muzzle brakes, nothing too complicated or that required a screw like this.

The screw looks vaguely familiar but I can’t place it, and I have no memory of losing any parts that I’m aware of. Can anyone recognize what this could be for or what it may have come from? I’m thinking it’s from an AR, but I checked those too and still can’t figure it out. Everything I have seems to be working just fine, for now anyway . I’m hoping the MDS brain trust can clue me in, because it seems I’m drawing a blank.

 

[NateIU10]

Got any ARs with a low profile gas block? Looks like a set screw.

 

[3paul10]

I'd say gas block screw too

 

[AlBeight]

None that I touched for any reason. Oh, wait... I did take the front A2 sight & standard plastic fore end off my AR-9 in favor of a new Hogue round tube front end and red dot. I remember driving out the 2 pins in what would’ve been the sight/gas block but since it is a blowback design there was no gas block and tube or hole in the barrel. Perhaps there still was a set screw? You guys may have nailed it. I’ll check in the AM, that sounds reasonable. If I only knew how long that screw has been rolling around my basement floor I’d be better able to figure it out.

 

[3paul10]

I can't think what else would have a set screw with that set up.....maybe a free float rail in the past?

 

[AlBeight]

I can't think what else would have a set screw with that set up.....maybe a free float rail in the past?

I was leaning towards handgun sight set screw, either front or rear, except I haven’t messed with any of them either. I do remember, albeit vaguely, removing or installing this type of screw at some point that is escaping me at the moment. I’m liking your gas block idea better at the present. If I wasn’t already in bed and exhausted I’d go check now..... Thanks for the suggestion(s), been driving me nuts all night.

 

[K31]

Do you reload?

 

[mopar92]

If you have an Aero Precision lower it may have came as part of the rear takedown pin parts kit. Some of their lowers can retain the detent this way.

 

[AlBeight]

Do you reload?

No I do not.

 

[AlBeight]

If you have an Aero Precision lower it may have came as part of the rear takedown pin parts kit. Some of their lowers can retain the detent this way.

No Aero Precision, but thanks for the idea. I’m gonna run thru all my AR’s and check thru that area on each.

 

[DivingDriver]

Do you have an arm brace that slides. Some of them have a travel stop and that looks like a screw that would be utilized.

 

[AlBeight]

Do you have an arm brace that slides. Some of them have a travel stop and that looks like a screw that would be utilized.

I do not, but thanks for the idea.

 

[ToolAA]

 

[DivingDriver]

Somebody's thinking

 

[AlBeight]

That is awesome.

 

[AlBeight]

A light bulb just went off finally. I have an H&R 12 gauge Ultra Slug shotgun that has a hammer. I had to replace the Uncle Mike’s hammer extension that I originally installed on this with an H&R OEM model. The Uncle Mike’s one kept loosening and falling off because of the loosening......set screw. I did this replacement on my work bench just prior to Opening Day of Firearms season last year. The H&R version has been rock solid ever since, and its screw is an even smaller hex key size. I do remember getting mad at the first piece and chucking it. Wish I’d have kept it for confirmation, but right now I’m about 85% convinced I just figured out my answer.

I’m still going over all the areas you guys suggested, just in case. Thanks for everyone’s help in my “quest”.

 

[dist1646]

I'm going to guess it came from one of the muzzle brakes. May be an extra as sometimes the mfg will put one in the parts bag.

 

[AlBeight]

They were all thread on brakes, no set screws. One Silencerco ASR and two Area 419 Hellfires. I like the suggestion though, and truthfully.....I did just go back & double-check that anyway.

 

[Rick3bears]

Marijuana is a terrible thing.

 

[AlBeight]

Marijuana is a terrible thing.

WTF does this have to do with anything in this thread?