Duffy
05-27-11, 15:06
This is a subject that comes up now and then, so we'll stick this here to serve as general information, as it applies not only to our own selectors, but all selectors.
There is a gap between the underside of the selector lever and receiver wall. The extent of the gap is a matter of receiver thickness.
We took measurements from couple of dozen receivers before deciding the length of the selector center.
What it comes down to is the thickness of the receiver. The milspec thickness is .880 +.015 -.002, or .878 to .895. We based our selector axis off one of my Colt SP1s, which is 0.898 and on the thick side. Even within the same company, there are variations.
This is a factory selector on an AR10
http://i75.photobucket.com/albums/i314/Duffypoo/Armalitefactoryleverleftprotrusion.jpg
This is the prototype selected for production, after we've reworked the length of the selector center. The difference in amount of gap between the left and right is 0.01, the reference receiver is a Colt SP1.
http://i75.photobucket.com/albums/i314/Duffypoo/Mod0protrusionsonColt1.jpg
CASS-3P, M16 (picture taken before our patent paperwork was filed to mask the patent pending dovetail interface)
http://i75.photobucket.com/albums/i314/Duffypoo/bothleversfromunderthereceiver.jpg
Colt, Bushmaster Armalite, DPMS, LMT and KAC are all pretty well within specs. POF and another billet lowers are notably thicker, at 0.905 and 0.911, while Olympic Arms are notably thinner than specs.
There's NO way to make a safety selector and have it fit flush with all brands of receivers, as mentioned, even within the same manufacturer there's slight changes.
The same ambi selector that fits flush on a Bushmaster, LMT, and KAC will almost be too tight for a POF. With a standard, non-ambi selector, this isn't an issue. If you haven't noticed, the axis usually sticks out a little on the right side, while some don't. This can be a problem for ambi selectors, too much protrusion on either side, it won't be as low profile as can be, and the lever will pinch your finger when you rotate the lever from Safe to Fire while its extended in the "finger outside the trigger guard" position (this is actually somewhat unavoidable, we just try to minimize the pinching).
There is no problem with the lever sticking out and not sitting flush (it will never be flush, the original Stoner design calls for a gap between the lever and the receiver, and for good reasons). In terms of rounds fired, eight M16 with our selectors had 100K rounds through them in less than four months without any failure. Semi auto selectors have far more rounds fired, as there are more semi auto selectors in the hands of users :ph34r:
There is a gap between the underside of the selector lever and receiver wall. The extent of the gap is a matter of receiver thickness.
We took measurements from couple of dozen receivers before deciding the length of the selector center.
What it comes down to is the thickness of the receiver. The milspec thickness is .880 +.015 -.002, or .878 to .895. We based our selector axis off one of my Colt SP1s, which is 0.898 and on the thick side. Even within the same company, there are variations.
This is a factory selector on an AR10
http://i75.photobucket.com/albums/i314/Duffypoo/Armalitefactoryleverleftprotrusion.jpg
This is the prototype selected for production, after we've reworked the length of the selector center. The difference in amount of gap between the left and right is 0.01, the reference receiver is a Colt SP1.
http://i75.photobucket.com/albums/i314/Duffypoo/Mod0protrusionsonColt1.jpg
CASS-3P, M16 (picture taken before our patent paperwork was filed to mask the patent pending dovetail interface)
http://i75.photobucket.com/albums/i314/Duffypoo/bothleversfromunderthereceiver.jpg
Colt, Bushmaster Armalite, DPMS, LMT and KAC are all pretty well within specs. POF and another billet lowers are notably thicker, at 0.905 and 0.911, while Olympic Arms are notably thinner than specs.
There's NO way to make a safety selector and have it fit flush with all brands of receivers, as mentioned, even within the same manufacturer there's slight changes.
The same ambi selector that fits flush on a Bushmaster, LMT, and KAC will almost be too tight for a POF. With a standard, non-ambi selector, this isn't an issue. If you haven't noticed, the axis usually sticks out a little on the right side, while some don't. This can be a problem for ambi selectors, too much protrusion on either side, it won't be as low profile as can be, and the lever will pinch your finger when you rotate the lever from Safe to Fire while its extended in the "finger outside the trigger guard" position (this is actually somewhat unavoidable, we just try to minimize the pinching).
There is no problem with the lever sticking out and not sitting flush (it will never be flush, the original Stoner design calls for a gap between the lever and the receiver, and for good reasons). In terms of rounds fired, eight M16 with our selectors had 100K rounds through them in less than four months without any failure. Semi auto selectors have far more rounds fired, as there are more semi auto selectors in the hands of users :ph34r: