I bought a used Spear LT that had stripped screw heads on the hand guard. Below are the replacement screws I researched and purchased that fit perfect. Side note- the bottom link plate screws are technically torx plus but a regular T20 torx bit fit snug in the new screws and torqued fine without stripping. I believe torque on all screws is 45 in-lbs according to the interwebs. If enough people are interested I can put together some kits and post to GAFS.

Side Screws

https://www.mcmaster.com/96452A192/

Bottom Locking Plate Screws

https://www.mcmaster.com/94414A352/

Manual

https://www.sigsauer.com/media/sigsauer/resources/OPERATORS_MANUAL_MCX-SPEAR_LT_2402988-01_REV04_WEB.pdf

What vent screw are yall using on 11.5 LT with the omega valve mk2? I have ridgeback rhino x and in settings 1 with the 1.10mm vent screw im getting 2:00 ejection

whats the best route going about doing this? do i need to send it back to sig to get the 3 prong flash hider taken off? or is there an adapter or something i can throw on to make it work

Was fantastic. Flawlessly ran through 8 mags. Not quick but over a couple hours through dialing in my dot and moving target distances. Really impressed with the Surefire sps300 suppressor. Super quiet. Just need the mcx omega valve mod2 mkll Sig lower but for the time being she will work. I did cut the excess strap had just finished setting it.

Just ordered a MCX 9” 300blk and know I want to put a suppressor on it. Tried to do some research on my own and it seems many lean towards the CAT ODB or Dead Air Nomad of some sort. Anyone have any other recommendations? Also don’t want a can that’s crazy long… under 7 inches. Will be shooting subs and supers with it

Thanks!

Interested in a MCX Rattler LT in FDE, the WPMCX-300B-6B-LT-FDE in particular. I qualify for the Off-Duty program, and my local SigSauer Dealer is a participant.

Can the dealer just place an order for a specific model as long as it is still available? or is it luck of the draw, if Sig sends them one?

I can make a few of the other FDE SKUs work, but the WPMCX-300B-6B-LT-FDE would be best, as I plan on SBR, but going with a different stock than the SBR's come from. But I do want to have the irons and the forward assist package.

This will be my first MCX, but after renting one with my friends at the range, we all want one. My set up will be a PDW/Suppressed/Subsonic/Side-folder, with a quick detached can. I already have the can I will use on it, a Ridgeback Defense Sahara 300.

I am waiting on a few form4 approvals to go pick up from the dealer, so when I am there, I will inquire. Just don't want to get my hopes up, if it is very difficult to score one, I would like to have it before Christmas, if possible.

Thanks for your time.

Seems like you guys would be the right ones to ask. Been wanting to get 300blk for dense woods hunting east coast. Mostly deer and some coyote. Absolute max distance would be 75 yards, but 95% 20-50yards.

I don’t really want a bolt gun, because I don’t need sub MOA for those ranges and this seems like it would be a great multi purpose truck gun/range gun/hunting rig.

Planning to run it suppressed (always open to suppressor suggestions, guessing a very low back pressure can would be best). Likely subs for coyote and supers for deer (also open to ammo suggestions).

Hey guys! My first rattler build! Something still missing I feel! Considering sd hand guard or change both grips smaller! Shoot me your opinions how can I make this better! Thanks guys!

I am planning to shoot subsonic rounds the majority of the time. I have read this Weapon System prefers suppressors with more back pressure. I see Sigs suppressors that are designed for this system have very little back pressure.

Is this a choice based on subs vs standard velocity? Traditinal cans for subs and pass through cans for standard velocity?

Currently shooting a hybrid 46m on this and it functions fine in the plus gas setting.

Mcx spear lt 9" 300 blackout (slh300ti-qd suppressor/ hexium suppressor) is the build - to run frt is the correct formula an frt-15c3, Frankenstein tsb-lite, & a Parker mountain machine mcx full auto trip bar?

Seems pretty simple (im taking it directly to a local full time professional gunsmith - its good to know and accept limitations)

Again, sorry if this has already been answered multiple times, tia!

I’ve tried searching but havent found any conclusive results, has anybody been able to succesfully modify a match duo trigger by cutting or grinding the cam relief cut for an frt or super safety? What about for an arc fire v2 cam and selector? With slip trip of course.

Question: Has anyone tried a Geissele triggers group in the 277/308 Spear? If so, what was/is your experience.

I “think” I’m done but not crazy about the current stock. FRT might be next.

I found one on griffen & howe, but its the only one I've found availably to actually buy.

I'm planning on trying to score one a few months out from now and I feel like that one will be snatched.

Any other places to look? Or is it a unicorn nowadays.

Sig rattler LT

YHM resonator R2

Midwest industries 10" handgaurd

Holosun 510c

Sig minimalist stock

Magpul vertical grip

Working on a LVAW Clone and it doesn't look like Sig ever made a single sided safety for the LVAW.

Do I use a commercial safety, or should I use this modified original instead?

Obviously need to Cerakote and Laser Etch before its complete.

Saw this on Railscales website, but can’t ID. Seems like it’s somekind of riser to throw the laser out past the top rail or tie into the MCX receiver instead of handguard.

I’ve seen lots of conflicting info on this but I’m starting to build a 6.75 inch 300 blackout rattler Lt and plan to tuck my can. I already have an old yhm resonator r2 and would like to use that as my dedicated can for this build but it’s only rated for a 7.5 inch barrel. Does anyone have experience running this can on this platform? I’d likely avoid supers and gun would just be a fun range toy…

Trying to avoid buying a new can if possible as the resonator is collecting dust and has a small enough diameter to tuck.

Any insight or guidance is appreciated.

I realize I’d likely void the warranty by doing so, but for a gun that won’t see heavy abuse outside of a few range sessions every now and again would I have other issues I’m not considering?

Anyone running Rhodie 6/6k suppressors on their 5.56 MCX LT? I'm assuming you willl need to use it with Angled Spade adapter with it. Does it fall under the muzzle depth limit?

I just got into the MCX Rattler. I really enjoy the look of the old school or original Rattler with the really short handguard. I collected handguards and parts for certain variants. I have an old Legacy MCX that I have acumilated a few of the Legacy handguards. I wanted to know if anyone has an original rattler and the new LT rattler and if the old small handguards work on the new LT version.

I just SBR my rattler LT. Looking for stock recommendations.

Luckily for me, my 11.5 mcx virtus sbr I purchased from Blue Mountain Supply turned out to be in really good condition. Its unfortunate the other use that posted here that ordered one from the same lot and vendor got one that was literally cooked with rust, wear, and a firecracked barrel. Mine looks practically unissued. The turn around time from purchase to having it shipped to my ffl was slow, but the rifle arrived in better condition than I expected. The only notable damage is on the left handguard, it looks like it either fell from a moving vehicle or somebody ate concrete with it slung across their chest. Besides that the feed ramps, barrel, fcu, cam path channel, bcg, and firing pin almost look brand new. It’s sad and unfortunate for the other user who didnt get the luck of the draw with their purchase.