10.5 LWRC upper, Suppressed with an H3.
It will only select fire reliably if in Normal gas mode, S mode I get LPS or fail to fire hammer dropped. S mode is so much nicer recoil impulse though, Is there anything I can do to get it working on S mode reliably without removing the can?
Isnt S mode made for cans and increase reliability?
Whats the firing pin protrusion? Min. 028”-.035” Max. Try an H2 buffer?
What did LWRC say when you called or emailed them?
That’s confusing. Light primer strike or fail to fire hammer dropped would indicate bolt carrier bounce. In S mode the rifle should be getting less gas which should mean that carrier bounce is less likely. I’m interested to see what the solution is.
The fact that something from LWRC will run at all is a miracle. Buy a lottery ticket.
Check for empty mag lock back in semi on setting S.
Possible issue with the auto sear?
If you’re saying that on the suppressed setting it won’t run without a can, that’s the whole point. To Clint’s point, the autosear adds drag on the carrier, which is moving at lower velocity on suppressed setting without the can. A light primer strike occurs on essentially all chambered ammunition in an AR that lacks a firing pin spring. The dead hammer on a live round sounds like bolt bounce, but that doesn’t make a whole lot of sense in this scenario. It’s worth a call to LWRCI.
All shots fired with a can, I will not be using this upper without one. Too much blast.
N mode functions as should on Semi/Select/ bolt lock on last round ect.
S mode does not function reliably with select, but works and locks bolt on semi with last round.
Lower is using a Maxim Defense PDW with a H3 4.85oz
This upper does work on S mode in Select with a standard Milspec buffer tube and Spikes T3 installed. I just prefer the shorter PDW if we can figure out how to remedy this.
The Spikes T3 is shown as being a 5.4oz buffer. I still suspect carrier bounce, but honestly don’t know anything about the Maxim Defense PDW. Just curious why you’re running a brace on a machinegun.
Extremely long day testing it, different buffers & springs & cans. She will not run more than 4-5 round bursts in S mode with any combination of buffers springs or cans. Switch to N and its flawless even mag lock on last round.
Since Maxim only makes an H3 (4.85oz) is there a way to modify it heavier or dare I try the JP silent capture spring?
What gas system does your upper have? I mean, is it what they call a piston system? Or is it direct gas?
really helpful lol
It was a question, to try and help you based off the answer
You already have the solution, though, use a carbine or a5 length buffer system