M*CARBO Brotherhood

Front Sight Post Upgrade



The AR style front sight post just screws right in to the S2K front sight.


Uuh,isn’t that backwards? :grin:


Nope … recent production factory peeps are taller than early production factory peeps. The comparison photo posted shows MCarbo v, Kel Tec’s earlier production. The MCarbo notch rear sight is taller than all the peeps.


You could grind the bottom of the sight threads off a little to get lower/further. If you do, perhaps find a nut that fits the threads snugly and thread it on before grinding or cutting. When you thread the nut off, it should help smooth out the cut end.


@Soundave I have since installed the Red Lion front folding sight which is a much nicer unit than the stock S2K front sight.


That is freaking brilliant! So simple and obvious…and I never would have thought of it in a million years. Guess that’s one of the tips the machinist guys keep under their hats. Or I’m just dense - which is a very real possibility. :confused:


We agree on the facts. See my linked post above which is reproduced below. I was just asking whether you inadvertently got your wording reversed since it is the recent post-2018 S2Ks that will see relief with a taller sight and the older pre-2018 ones that have the shorter but better quality piece with no seams or excess flashing.


Umm I think your confused. Pre 2018 S2Ks have the shorter rear sight. Meaning that installing the MCARBO rear sight will give better eye Relief. If you have a newer S2K the MCARBO sight just means better quality and materials.


@aadavis94 I am NOT confused but I respectfully am finished posting words that are not read carefully. The only reference I have made to the MCARBO sight was to point out in my earlier post that the new KT sight was essentially the same height as the MCARBO Peep. I never drew any comparison to the MCARBO sight in my dialogue with @Dred. Read the words and look at the photos in the linked post.
The older KT sight is shorter than the new KT sight. See the post I have now linked twice. @Dred and I were talking (I think) about the two KT sights and not the MCARBO one since the new KT sight is basically the same height as the MCARBO Peep.
I have said nothing about the MCARBO Notch which is taller than any of them.

So you are correct that installing the MCARBO sight will give better eye relief to those having the old KT sight although that was not my point. So will installing the new taller $5.00 replacement sight from Kel Tec which is about the same height as the MCARBO Peep.


i think this is backwards. the ‘newere’ production will see relief, not the pre '18


hmm, thanks for the clarification


agree, i think. the NEWER production will see the relief, not the older production


I ended up using mid sized.


Just screws in be careful though of the detent pin. It can pop out and be difficult to find. So be in an area with wood or tile floors and away from floor vents. :+1:


FYI, I ordered spare spring and detent pin for front sight. The detent pin was $4 and the spring $1.


Fortunately learned that in Junior high shop class a few decades ago. Has helped a ton of times.

Sadly, no more shop class taught in schools, do this tip may become extinct


Does anyone have a link for the tool that will work on the gen 2 front sight post? I recently purchased a 4/5 prong from Amazon and it doesnt fit (too small).I just do not want to purchase another that won’t work.



@S2K Any genuine GI sight tool with 4 prongs should work just fine.


i use the KNS combination tool AR 15/ AK 47 PSA sells em, i paid 12$ and change for mine back at Christmas.KNS%20precision%20front%20sight%20adjustment%20tool%20combination%20AR15%20AK47


@GOBLIN It’s about time someone put a da** (T) handle on them ! :joy: