Have an Armalite Flatop carbine with their Mid. lenth upper, would like to use a RAS type setup on it for a pistol grip and light, any options.
Thought about shortening one of the Olympic arms forends but Im not sure.
Does anyone sell picatany railsthat mount to a floating forearm?
Thanks

Blkbrd,

Can you do me a huge favor?  Please measure the length of your mid-length forend tubes.

Now, depending on what that length is, you may be able to use a FF RAS as MSTN is selling here www.ar15.com/forums/topic.html?id=96965

In order for you to use a different forend you will need to be able to remove your front sight which in turn will require that you do not have a perminant break mounted on your gun.  If the break is permant, then you will need to seriously consider if you really want to do this!

If you do not have a free float (match) forend, then there are rails that will mount to your carbine grips that will allow you to mount accesories.  Please post more details about your upper AND PLEASE POST THE LENGTH OF YOUR FOREND GRIPS!

I too need this info.

The length of the handguards including ring engagement surfaces is 8 5/8 inches.
I currently have an Advanced Armamant rail mounted to the lower handguard with a handle and light, however the handguards are to flimsy for this to work well, they flex like mad when in use.
I refuse to pay the price that Knights Armemant is getting for there Full floating RAS.
Its fine with me if they gouge the military for tooling but i'm an ex machinist and these are not aircraft parts.
I am having Kurts Custom put on a different brake and will be doing work at that time.

Sorry, I missed when you had posted this before!

The measurement you gave at 8 5/8-inches and the advise that I was given at www.ar15.com/forums/topic.html?id=64240&page=1 that the Armailie Mid-Length upper is 11/16-inches too long to correctly mount a bayonet is quite interesting news!

This combines to mean that if someone was able to find a KAC Medium Short FF RAS tube (7 5/8-inches in length) (which I have) and build a 16-inch barreled upper.  Now, as long as I move my front sight base towards the muzzle of the barrel about 5/16-inch then I will have a 16-inch upper that will accept removable flash supressors and CORRECTLY mount a bayonet!

This is the same measurements I got working in the opposite direction as I described on this page www.quarterbore.com/300whisper/my300whsp.html

Thanks for the measurement!

Also, nobody answered your questions.....

To my knowledge there is nobody that is making a system for the mid length carbine.  I did look at using the M5 RAS with my DCM FF tube and I think that it would have worked if I cut out the heat shields.  The M5 RAS was just too expensive for me to try it so if anybody wants to try, be warned that I am not saying it will work!

As for cutting down a FF tube, that is probably the only option and god knows that this is done all the time for pistol and other special shorty tubes.  You may also consider just getting a traditional tube shortened and then attach the MIL-STD-1913 rails yourself.  Then you can get creative and make a better mousetrap that will be unlike anything on the market!

Good Luck!

Quarterbore;
That is quite a project you have going, but with those measurements don't you just end up with a carbine anyway?
I have obtained an Olympic rifle freefloat tube and plan on cutting it to length. If I use this tube that is, It is a bit rough.
This project may be going on the back burner due some new toys in the works though.
Good luck with the .300 whisper project.

YES, but a carbine that has a 16-inch barrel (NON-NFA-LENGTH) so I can have a removable flash supressor.....  PLUS..... use a bayonet!

Show me any other AR-15 carbine upper that has these features!

Armalite and RRA really screwed up with their Mid-Length uppers and I am shocked that KAC got it right and hasn't eaten these guys' lunch!

www.ar15.com/forums/topic.html?id=97453