Has anyone modified their Five Seven conversion bolt for use with a RR M16?  Is there a gunsmith that can get this done?

TAG

I swear, I was just thinking about this the other day and I don't think it'll work.

Just like the bolts on some of the piston or piston hybrid AR's out there, FA FCG's may not interact with the BCG correctly.

Oh it can be done, see link: Link to Youtube vid of full auto Five Seven upper

Post Sample

That means its got the factory sear. I wonder if it'll work in a RDIAS weapon?

I don't see why it wouldnt be possible. The ar57 upper from 57center.com uses a standard ar15 lower. Assuming they come out with a FA carrier and further assuming the trip on an rdias puts the sear edge in the proper place, there's no reason it shouldnt work.

It will work.

I e-mailed them and, once the FA bolt is available and I show them my Form 4's (RDIAS and SBR) they'll sell me an SBR upper w/FA bolt!!!!

Puts them right in the game w/being considered for another upper for my MG's!

I spoke with them today and the bolt alone was supposed to be under $200 complete. I can't wait!

This^.....it'll be sick!

It can be done.

Video of my 5.7 upper on a postie lower

It wasn't hard to do.  However, after some reflection, you will probably want to trim the front trip contact surfact 1/10,000th" shorter than a standard M16 BC, AND, you need/will want an anti-bounce buffer which will be available from 57center.com 'shortly'......

Have fun.  It's cheaper than 5.56 right now and 50 rd mags are a bonus

Front trip contact? On my BCG? 1/10,000 of an inch? Really?

Please wait until you actually have one in your hand before acting like you know what you're talking about.

Yep, straight from 57center (I had a friend weld my bolt for me to M16 specs) and 57 told me to shorten it 1/10,000.  

BTW the 57 upper doesn't have a 'BCG' per se- the whole schebang is one piece 'bolt'.  Don't modify your FA Bolt that you get from 57 center as they will already have made it the 1/10,000 shorter.  They will also probably include an antibounce buffer that you will want/need for a little safety.

The guy I talked to at 57 told me the F/A bolt and buffer will be sold seperately from the semi-upper. Apparently no option of semi or full; to get full, you have to by both.

Full auto bolt and buffer is now shipping from AR57center. Cyclic rate is suppose to be 750 RPM.

Ordered up an SBR upper and F/A bolt. Hopefully will get to the range this weekend.

Did you get to the range yet?

(1/10 000) of (1 inch) = 2.54 microns

You are much more precise with your Dremel than I am with mine...

just my .02¢,
WhyTanFox
"scale is important'

Yeah you're right I meant 10 thousandths....

That's what I was trying to say...1/10,000 would be nearly impossible to 'tell' from one BCG to another w/the gear I have at home (or just about anywhere else I go).

Wasn't trying to make fun...I really couldn't believe you'd expect/ask someone to trim that little off a random BCG.

I have a FA bolt that I modified.

I also bought a FA bolt and buffer from 57 center.  Their full auto buffer weighs 5.7oz and has an anitbounce weight installed.  For the record, their semi buffer weighs 8oz.  Both are the same length.

First off, the trip contact surface is NOT identically spaced to the M16 BC.  This added distance/delayed trip time helps to account for the non-locking/blowback nature of the mechanism.

I took my new/factory setup to the range and had several hammer down on live round malfunctions (no primer ding).  In addition, there was (in some instances) severe deformation of the brass (shoulder visibly displaced forward) resulting from bolt bounce with ignition.  Also, I measured my ROF to be in excess of 900 rpm using my pact chrono-timer.

I called 57 center, talked to their technical guy,  and I'm gonna try changing a few springs but so far I'm skeptical.  They were quick to point out that my M16 is a postie and not factory colt or bushmaster.  Why my postie lower would work with spikes 22 and all other uppers but theirs remains a mystery to me.

If you want my opinion, my welded BC and 8oz buffer worked better than their 'factory' setup, but like I said I'm gonna try changing a few springs and see if that makes any difference.

I received my factory SBR upper and FA bolt a few weeks ago. Works been a bitch and haven't gotten to the range yet. Hope to this weekend and report. I'll probably bring my assortment of buffers.

More anon.