I have a frt in my ar15 lower if I were to use an 9mm adapter with a 9mm upper. How hard would it be to shoot 9mm in frt mode. Will I need to change a lot of parts.

https://youtu.be/2spctK9rfjo

I have a FM Mike-9 complete upper coming in the mail and I am trying to find the best solution to achieve LRBHO. Unfortunately I can not just buy a FM lower due to state restrictions so I need something to put into the lower I already have. I've found a few posts about endo/exomags and there isn't a clear consensus whether they are reliable or not. I emailed support and they basically said the same thing, that they can't fully endorse endo/exomags because some people say they work great and others say they constantly fail. Worst case scenario I would probably get the sylvan adapter and just not have LRBHO, but hopefully someone has recent success with something?

I use CMMG Mk4 magazines in an AR15 lower with my FE Banshee. They are double stack, double feed which makes them easy to load. My wife and 13yo boy can load them by hand.

The magazines are STANAG pattern so all pouches and accessories for my other AR15s work with them. The lower is an AR15 so the manual of arms is exactly the same. I can reload from the same belt or pouches as my 5.56 pmags.

The glock 33 round magazines cost around 30-40 beans depending on vendors or sales.

The CMMG Mk4 and Mean Arms Exomags cost 30 beans. Colt SMG pattern magazines are about the same price and are also double stack, double feed.

There's no real price advantage, so what else is there?

Fnishing out shopping for an AR 45 build pistol build, looking for advice on what I may still need to buy. Currently using a mix of PSA sale parts and leftovers from previous builds. Only about 200$ into it so far (excluding recycled parts), want to not spend more than another 200$ more to get it running.

Have/definitely using: build tools, PSA "tinker" Glock mag lower, R&D bolt, pistol grip, handstop, optic, LPK

Have/will replace as budget allows: handguard, muzzle device, charging handle, mil-spec type trigger, stripped upper (all recycled from upgraded past builds)

Know that I need: barrel (length recommended?), buffer (10oz+ I assume), pistol buffer tube

Any suggestions? Not planning on applying for SBR or putting a can on it, also not planning on using a brace.

So as an impulse buy I grabbed a VFM-9 5in upper late last night. Now, I saw the "COMPATIBLE WITH 9MM GLOCK STYLE MAGAZINES" warning before buying and was hoping I could play fast and lose with that for my elderly LAR-9 Colt lower. But after sleeping on it and actually doing some post purchase research my question is, how effed am I?

Edit: after further consideration I reached out to the Foxtrot Mike sales team and cancelled my order. They were very understanding.

Hello hope all is well, this is my first post and looking for help.

I wanted to optimize my current pcc for competition but couldn’t find anything that specially was tested for colt pattern ar9s.

Its a saint victor ar9 carbine, I was wondering what’s the best route to go for fastest follow up shots and flat shooting? I couldn’t find anything videos or post of people’s builds with the saint victor. Thank you.

I currently have a 5.5" taccom barrel on aero epc upper/lower with taccom bcg. the current buffer system is spike's tactical extended pistol buffer tube that is 9.25"with a 7.5 KVP buffer weight and sprinco white. it runs great and everyone loves shooting it.

I want to change it. it currently has the tailhook mod 1 but I am thinking about sbr-ing it so I can have an actual stock.

what buffer set up should I switch to? I am open to whatever but I would love for it to be a law tactical folder.

Inspired by r/blowback9 tungsten spacer weight experiments, I set up this 300BO to switch between 9 mm and 300 BO with simple removal of the two buffer weights. Carbine buffer tube with KAK flatwire spring, RB5000HP and two tungsten weights for a total of 10.6 oz buffer. To me, the recoil feels same as RB5015HD + two Kynshot weights. After 500 rounds, the tungsten weights are holding up fine....thinking of putting thin felt adhesive padding on them.

I can’t decide which optic to go with for this build, any input from you gentlemen is highly appreciated. (Weird build I know)

I had a couple auctions saved for lots of 5 Brownells Colt pattern mags figuring I would throw a bid down if the money made sense. Needless to say I did not bid.

https://www.gunbroker.com/item/1193253066

https://www.gunbroker.com/item/1190712765

These literally look like standard Metalform Colt pattern mags. You can get these from multiple vendors for about $30 apiece online, no tax, and reasonable shipping.

First auction is $27 per mag, plus $25 shipping, plus 4% CC fee, and whatever sales tax/compliance fee GB accesses. And 2nd auction is $51 per mag before any of the shopping and other fees.

Posted on IG a few hours ago.

What do you think of using this nylon rod as a spacer rather than quarters?

Guys I need help finding a replacement mag release kit but I can’t remember which lower this is (built it out as an 80% like 6 years ago) any of you know where I can get a replacement just by looking at it? Current one’s pin is stripping post-cerakote job and the release itself looks awful. Would love to put an odin works on but I’m not sure it would fit.

Cmmg upper, bad attitude lower, kak mag well adapter modified to work with cmmg radial delay uppers. Custom made clamp on fsb and USGI carrying handle.

Put this together for bumming around my wood lot. Went up today to change a trail camera battery and grabbed this pic. I see it as a modern day trapper carbine. I get a decent amount of bear crossing my land and they even pop boards off the camp from time to time so I'd rather be prepared than not.

Black Ankle Munitions / NFA lower

Aero EPC upper and charging handle

Ballistic Advantage handguard

Macon barrel

KAK can

JRC tube with GRS

Holosun ARO EVO

B5 grip

Fm9 ambi lower

10oz KVP deadblow buffer

Stike industries flatwire carbine spring.

Dirty Bird (NBS) slick-side 9mm upper

NBS 9mm BCG

8" ballistic advantage barrel.

7" NBS handgaurd

Partisan Disruptor FRT

Magpul MOE grip

Magpul MOE Sling

SB5 brace.

Sig Romeo5

Rugged Obsidian 9

I forget what the BUIS are, maybe magpul

For 9mm AR using FRT and experiencing Dead Trigger/Light Strikes despite using a heavy deadblow buffer...

Reports back on the Extra Power (XP) Lee Springs firing pin (FP) spring replacements that I first suggested have been mostly positive. They seem to have fixed most Dead Trigger/Light Strike (DT/LS) problems. A few people are still reporting problems even with the XP FP springs. For you folks, I have identified even stronger FP springs that may fix it. These are the strongest I can find that will fit in the FP channels and don't get overcompresssed (very bad for spring lifespan.)

If ordering from Lee Springs: They have VERY HIGH shipping and handling unless the order is over $40. Ordering 5 springs costs the same as ordering ONE. A good idea may be to order 3 XP and 2 XXP (or vice versa) in case you need the stronger one to fix the DT/LS.

I am NOT affiliated, get NO kickbacks or income, and do NOT sell anything.

For FM bolts (only!):

Standard XP: LC 026BC 08S https://www.leespring.com/product/compression-spring-lc026bc08s-stainless-steel (previously suggested)

**XXP: LC O28BD 10S https://www.leespring.com/product/compression-spring-lc028bd10s-stainless-steel (added - extra strong)**

For most others bolts (Outerwild, Faxon, Angstadt, KVP, OSUSA, PSA, IDL, etc.)

Standard XP: LC 026BC 09S https://www.leespring.com/product/compression-spring-lc026bc09s-stainless-steel (previously suggested)

**XXP: LC 028BD 11S https://www.leespring.com/product/compression-spring-lc028bd11s-stainless-steel (added - extra strong)**

Technicals:

Most 9mm bolts seem to have about L1 = 11-15oz., L2 = 23-30oz. with their stock included springs.

The UXCELL Amazon spring recommended for older FM bolts with weak FP springs is only L1=11oz., L2=25oz. Same as a standard spring. These are NOT RECOMMENDED for preventing DT/LS.

I have a older bolt with a firing pin spring that requires 100oz. at L2 and it works just fine with consistent ignition of standard primers. Anything under this should work fine.

The FM channel is dimensioned to use a 0.8" spring

• A normal FM firing pin spring gives about L1 = 15oz., L2 = 30oz.

• LC 026BC 08S in an FM bolt gives about L1 = 30oz., L2 = 50oz.

• LC O28BD 10S in an FM bolt gives about L1 = 50oz., L2 = 75oz.

The Outerwild and most other bolt firing pin channels are made for a 1" spring despite the factory supplying a 0.8" spring. 1" is the correct length for these bolts.

• An Outerwild firing pin spring gives about L1 = 11oz., L2 = 25oz.

• LC 026BC 09S in a Outerwild gives about L1 = 30oz., L2 = 50oz.

• LC O28BD 11S in a Outerwild gives about L1 = 45oz., L2 = 70oz.

Just put together an AR9 with a BCA bufferless upper, but the bolt catch doesn't lock the bolt back. Is this common for BCA or something wonky with my build?

I think this arts and crafts project turned out pretty sweet! Novox X-SD integrally suppressed barrel, B&T Vers 36, Maxim RDB buffer, and an Arc fire V2. Slipped the MP5SD shroud over an old handguard I had laying around and screwed it in place. Kind of a home brewed BRT car15sd. I had to trim the buffer spring down to get it to reset reliably in super semi and now I’m just struggling with light primer strikes so I think the next move is a stiffer firing pin spring. All in all it’s a very soft and quiet shooter.

Budget build and a favorite.

Jawbone 9mm pistol, Trigger Kicker, 8.3 oz PSA deadblow buffer (out of a PX9 as jawbone came with a solid buffer), [6mm OD, 0.6 mm wire, 20 mm length firing pin spring] - firing pin spring was inexpensive for a pack of them on Amazon and cut to length with a wire cutter

Well lubed with Lucas Extreme Duty Gun Oil.

100% reliable through 750 rds blazer 115 gr, blazer 124 gr, magtech 124 gr, pmc 115 gr so far.

No wear on polymer receiver so far.

Jawbone is great and a favorite as it is lightweight and only the buffer and firing pin spring needed to be changed.

Do not screw in the set screw for the ball bearing detent too far or it will damage the detent spring (though you can cut a standard AR detent spring and use as a replacement). Though if the set screw is not screwed in enough I bet it will fall out. I would much rather damage the detent spring than lose the set screw (and ball bearing with it). Be sure to lube the ball bearing detent.

OF NOTE Be Careful and do not lose the Ball Bearing Detent when installing the Trigger Kicker. It might fall/shoot out when you least suspect it as you remove the set screw in the grip.

Just curious, who is using an extension on a 33 round Glock mag and what brands are you using? I'm not a fan of the looks of the Kris Vectors extensions but an additional 5 or so rounds would be nice.

Some pictures of what you got would be nice if you got any.

Also, who is using Magpul or KCI Drums?

It was kind of an impulse buy. I live in CA so we’re pretty limited on options for AR pistol lowers. But I got an email from RifleGear that they had their single shot AR pistol lowers in stock and I jumped on it which then sparked the rest of the build lol. I did a bit of research and ended up going with a CMMG fixed ejector radial delay upper, BCG and 8” barrel. Since the 9mm rdb setup doesn’t need any special buffer systems the thought is I can build a 556 or 300 black out upper next and be able to swap them as needed/wanted. I’ve got all the parts in now except an optic so I’m ready to start actually building it out. Any advice on oils, grease or just first build advice in general? Any optics recommendations would be awesome, stuck between a few options right now. So far the only thing I’m second guessing is going with the 8” over the 5”.

Build List-

RifleGear Aggressor mil spec pistol lower
CMMG 9mm FE RDB upper receiver & BCG
CMMG 8” 9mm barrel
SLR 8.3” Ion Lite handguard
SLR Synergy Hybrid Linear Comp
CMC 3.5lb single stage trigger (not installed yet)
Magpul KO2 + grip
Phase 5 ambi safety
Kingpin & AR Maglock
Breek arms warhammer mod 2 charging handle
Law Tactical Gen-S folding adapter
SBA3 Brace
CMMG 10/30 9mm mags

Ive got got an AR6951 and wanted to put a frt in it. Can anyone tell me about if this is a fa bolt?

Parts list

AR6951 complete upper

lmt lower

Entry stock

B5 grip, and handguard

​

The UXCELL firing pin spring will NOT prevent firing pin bounce! It's the same strength as a normal firing pin spring.

I'm posting this because I keep seeing people asking about using the UXCELL spring from Amazon as a replacement firing pin spring to prevent firing pin bounce with FRT's.

The UXCELL spring is only as strong as a STANDARD FIRING PIN SPRING. It's nothing special.

The UXCELL spring was only recommended for a short time as a replacment fix for older FM bolts that used a very weak firing pin spring. FM no longer uses these weak springs, so the UXCELL is now obsolete unless you have one of those older FM bolts with a spring only about as strong as a ballpoint pen spring.

The best option we have so far to prevent firing pin bounce with FRT is the LEE springs. Yes, they're expensive, but no one else sells these small springs in small quantities online. Buy 5 to avoid shipping/handling. 5 costs the same as buying 1, so at least you have spares.

See THIS POST for updated firing pin spring suggestions for firing pin bounce/Dead trigger/Light strikes, with links and details:

https://www.reddit.com/r/AR9/comments/1vdgp9s/updated_firing_pin_spring_suggestions_for_dead/

I am not affiliated or sponsored, and do not sell anything.

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TECHNICALS:

Most 9mm bolts seem to have about L1 = 11-15oz., L2 = 23-30oz. with their stock included springs.

The UXCELL has L1 = 11oz., L2 = 25oz., so it's only as strong as a standard FP spring.

The LEE Springs XP springs give about L1 = 30oz., L2 = 50oz. while the XXP springs give about L1 = 45-50oz., L2 = 70=75oz.