Gemtech Suppressed Bolt Carrier does not fit into the upper receiver

[sorvanetzsorv]

I have a brand new Gemtech Suppressed Bolt Carrier GSBC-5.56 that I purchased a while back but have never had a chance to use before. I am trying to install it into a mil-spec upper receiver and it cannot go in. The valve flange that is used to switch the mode from suppressed to unsuppressed seems to be sticking out a little bit too much (maybe by 1/16") and it hangs on the side of the upper receiver preventing the bolt carrier from going in. The valve is very easy to take out and put back in. So, I have tried reseating the valve several times, and the valve is definitely fully seated and cannot be pushed in any further. I tried several different mil-spec upper receivers - and the result is exactly the same. It seems to me that the valve is a little bit too long. I wonder if anybody has faced this problem and if there is any way of fixing it.

The problem is that Gemtech has been bought by S&W and the current Gemtech support is not in Idaho anymore, but just regular S&W support in Springfield, MA. This suppressed bolt carrier seems to be discontinued - no traces of it on the Gemtech website. If I am correct that the valve is out of spec, then the only remedy seems to be to replace the valve. I called Gemtech tech support and got some S&W people who know nothing about this product and cannot tell me if repair parts are still available. The only option they offered is to send the bolt carrier to them at my own expense, and then they will check it, and if they do not have the parts to repair it, they will return it to me. All my pleas to check if a replacement valve is still available were to no avail. I would appreciate any help.GSBC-5.56-r.jpg

[Defaultmp3]

Pretty sure that the GemTech was really made by Bootleg (AKA, PWS), so I would also reach out to Bootleg if S&W/GemTech ain't being helpful.

[DaBigBR]

I own both BCGs and they do appear to be identical except for the Bootleg one having four positions instead of two.

[georgeib]

This might be a dumb question, but is it possible that you have the valve installed 180° from where it should be?

[SteyrAUG]

Would also be helpful to know which "mil spec" upper manufacturer we are talking about. When it comes to ARs lots of folks actually have "house spec" that they refer to as "mil spec."

[sorvanetzsorv]

The uppers the BCG will not go into include Armalite M153GN18, Savage MSR 15 Recon, and I even tried (for the heck of it) Adams Arms (which has regular dimensional specs even though it's a piston gun). The valve cannot function if it is turned 180, so no - there can be no confusion about the direction of the valve. To have a better idea about this BCG, take a look:

https://www.capitolarmory.com/blog/g...er-review.html

[Dukr]

Could you just file/grind down the top of the adjustment valve flange?

[sorvanetzsorv]

I suppose the flange of the valve can be modified with something like a dremel but it's tricky to take off no more than needed, and then the valve will need to be melonited, and who knows whether taking off this metal from the flange will compromise the valve in any way. I am definitely not comfortable doing this.

[MegademiC]

Whoever made it, or bought the company who made it needs to resolve it.

My limited s&w experience has been positive.

[SteyrAUG]

The uppers the BCG will not go into include Armalite M153GN18, Savage MSR 15 Recon, and I even tried (for the heck of it) Adams Arms (which has regular dimensional specs even though it's a piston gun). The valve cannot function if it is turned 180, so no - there can be no confusion about the direction of the valve. To have a better idea about this BCG, take a look:

https://www.capitolarmory.com/blog/g...er-review.html

One of the things about the "old" Gemtech company is they tended to build shit compatible with Colt / KAC and that's about it. Anything slightly off those specs (which would include Armalite) might have fit problems. Not sure if the people currently working at Gemtech would be able to service their legacy products or not, but I'd drop it into a Colt first.

If it fits and functions in a Colt, just grab a Colt or sell the BCG to a guy with a Colt. It if still doesn't fit in a Colt, then send it to Gemtech because obviously you have a fit problem and hopefully they can correct it.