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Five-Seven MRD MkIII Threaded Barrel?

8468 Views 57 Replies 12 Participants Last post by  VariousCheeses
Hi, does anyone know if the threaded barrels currently offered for the MkII will work in the MKIII? Specifically I was looking at the EFK Fire Dragon and Jarvis barrels. I emailed EFK last week and have not heard back. Still waiting to hear back from Jarvis as well. Thanks
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Pointing out repeated errors by a self-claimed “expert” is “hostile”? Maybe I’m wrong, but I don’t believe the purpose of the forum is to be a “safe space.” Nor do I see it is a "hostile" or “toxic” micro-aggression to point out when an “expert” consistently posts objectively incorrect information. If I hurt or challenged your feelings in some way, I do apologize though. Objective facts are tough things to face sometimes, and are often difficult to reconcile with emotions.

Perhaps your concern might be better focused on others who might rely to their determinant on chronically wrong “expert” advice? That would certainly be hostile, hopefully only to the wallet, and not worse…..

No sure what specifically your “not just” comment refers to. Never my intent to wrongly micro-aggress. If you have a specific "not just" example, I will certainly re-review what I had posted, acknowledge any error, and apologize if I was wrong. I do try my imperfect best to take ownership and responsibility.
you’re a bit over the top and I’m not sure what you’re flipping out about. You seem like you’re flipping out about everything. Have you been hurt before?
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you’re a bit over the top and I’m not sure what you’re flipping out about. You seem like you’re flipping out about everything. Have you been hurt before?
Objective facts have been provided to anyone who might be interested. Sorry, but predictable ad hominem from various profiles has not, and will not work to cloud inconvenient facts. Nor will any other line of personal attack.
Okay, folks....trying to get back on topic...or rather, ask a question in line with threaded barrel inquiry....

Jarvis offers a recoil spring with "reduced power" that is reported to help with cycling issues when shooting suppressed.
Their threaded barrel ships with a standard weight spring.
Do y'all think that the "reduced power" spring is needed with a suppressor?
Just throwing it out there....
I would like to get y'all's thoughts on this.
TIA.

Edit: Update
Answering my own question...sorta....

I got a call back by Andrew Jarvis. We discussed consideration for the "reduced power" spring. He relayed that he recommends ordering the tactical barrel with the standard weight spring; trying it out; and if there are issues, then order the "reduced power" spring.

So, I just pulled the trigger on the tactical barrel and the thread adapter.

Additional info that I got from him and I thought might be helpful to folks here:
1. the included thread protector does cover all the threads
2. the thread adapter leaves about 1.5 exposed threads
3. the thread adapter design has been changed/updated so that it has got wrench flats just in case it is overtightened and gets stuck on the barrel or in the suppressor threads.
4. you do not need to apply anything to the barrel threads prior to engaging the thread adapter or other device

Hope that is helpful for at least one of y'all. Thanks.
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Yes since even with EA's 2 pound heavier recoil springs quality sub sonics still cycle just fine. Dropping the rate of the recoil spring runs the risk of frame damage.
Yes since even with EA's 2 pound heavier recoil springs quality sub sonics still cycle just fine. Dropping the rate of the recoil spring runs the risk of frame damage.
Gotcha. Good to know! Thank you for sharing that info.

So, for the time being, I only plan to shoot 27 gr (SS195LF and SS198LF) for now. I am assuming shooting through most suppressors rated for 5.7 ammo (except for the Bowers Bitty) will be hearing safe....of course, I could be assuming wrongly.

I am looking at suppressor options (mostly modular) to run so I can have this gun as my nightstand safe gun (i.e. to fit in my nightstand safe) and be hearing safe. Total length (the gun, adapter, and suppressor) needs to be a bit less than 13.7".
Just received email relaying that my order, which was placed at 1647 EST, has shipped!
Now, I gotta figure out which suppressor to run, order it, and painfully wait for it to be free....
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So, for the time being, I only plan to shoot 27 gr (SS195LF and SS198LF) for now. I am assuming shooting through most suppressors rated for 5.7 ammo (except for the Bowers Bitty) will be hearing safe....of course, I could be assuming wrongly.

I am looking at suppressor options (mostly modular) to run so I can have this gun as my nightstand safe gun (i.e. to fit in my nightstand safe) and be hearing safe. Total length (the gun, adapter, and suppressor) needs to be a bit less than 13.7".
Almost no suppressor for any supersonic pistol cartridge will be hearing "safe". The db or report of the fired round will be considerably more diminished and tolerable but will not be true hearing safe. I know it is also more recommended to use the 5.7 suppressed with the 40gr loads like SS197 as SS195 and SS198 are a bit hot through a can. I've shot both and done them outdoors with a suppressor, you'll live without hearing protection but I wouldn't sit there shooting mags just for fun.

FYI, I've only used my Spectre II's and Octane 45's on the FiveSeveN. The Octane was hands down more pleasant to shoot for both noise reduction and backpressure reduction. I also used a 22 endcap on the Octane, sourced from Griffin....made a little bit of difference in the noise reduction too. The Spectre II looks great size wise but just isn't close to performing as well. Now I have a Thunderbeast Fly 9 in jail, looking forward to the weight/size/performance of it on the pistol. Should be pretty awesome.
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Almost no suppressor for any supersonic pistol cartridge will be hearing "safe". The db or report of the fired round will be considerably more diminished and tolerable but will not be true hearing safe. I know it is also more recommended to use the 5.7 suppressed with the 40gr loads like SS197 as SS195 and SS198 are a bit hot through a can. I've shot both and done them outdoors with a suppressor, you'll live without hearing protection but I wouldn't sit there shooting mags just for fun.

FYI, I've only used my Spectre II's and Octane 45's on the FiveSeveN. The Octane was hands down more pleasant to shoot for both noise reduction and backpressure reduction. I also used a 22 endcap on the Octane, sourced from Griffin....made a little bit of difference in the noise reduction too. The Spectre II looks great size wise but just isn't close to performing as well. Now I have a Thunderbeast Fly 9 in jail, looking forward to the weight/size/performance of it on the pistol. Should be pretty awesome.
jaflowers, thank you for your detailed post. That is super helpful.
I do not plan to shoot 40 gr....at the same time, I think having a suppressor for my purpose makes sense even if what I am doing will not allow for true hearing safe shooting. I figure decibel reduction, though not below the hearing safe threshold, is better than none. Additionally, the efforts, time, and cost are still worth it....

I do not see many folks shooting mags just for fun given ammo cost. LOL. j/k.

I guess I was thinking that a "darn good enough" can could bring the decibel level of 27gr into the hearing safe range....and I had no good reason other than seeing this with 300 blackout. BUT that is not a good/fair comparison by any means....(sigh)

I will certainly look into those cans. I will also need to look into endcaps.

Thanks again!
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Hearing safe is subjective. Any noise over time will damage your hearing. OSHA considers the gun shots under 140db "hearing safe", but that can be very dependent on users. Super sonic 197/AE TMJ/ with a decent 22 can rated for 5.7 will get you 134-136 db. Subs will get you under 120DB in the pistol.
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Hearing safe is subjective. Any noise over time will damage your hearing. OSHA considers the gun shots under 140db "hearing safe", but that can be very dependent on users. Super sonic 197/AE TMJ/ with a decent 22 can rated for 5.7 will get you 134-136 db. Subs will get you under 120DB in the pistol.
this is very accurate regarding hearing safe. The tone also effects everyone differently. Exposing my ears to in laws constantly asking ****ing questions they’ve already settled on in their heads over and over again because they’re hoping for an answer from me to justify their idiocy has wreaked havoc to my ear drums!

Dead serious…my tinnitus is normally aggravating but when the in laws are here my ear dreams are screaming at the top of their lungs. The acute high pitched ringing from my tympanic membrane develops a deeper but louder noise that sounds like “SHUT THE **** UP!!!!” Over and over again.

my in laws are visiting this weekend for a few days. Super excited.

and also look into the dead air mask
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Yes since even with EA's 2 pound heavier recoil springs quality sub sonics still cycle just fine. Dropping the rate of the recoil spring runs the risk of frame damage.
OP asked about either standard or decreased tension recoil springs to max reliability when shooting suppressed --not whether he should buy a spring with increased spring tension.

If you "agree" with what Jarvis recommended, why are you dropping a reference to a product you sell with an increased spring tension? Seems a really strained gratuitous product placement.

Assuming OP uses ammo within CIP specs, wouldn't it be best if he does NOT buy your spring and to consider using 197 or subs instead of 198/195--- if his goal is to run suppressed-- like others have noted?

Would welcome seeing your "engineering proof" that a 2lb increase in spring tension does not have an effect on cycling subs. As you claim to be an engineer with multiple degrees, I am sure you are aware of Hooke's Law? You must have run those calculations, no? Spring tension is further dependent on pressure of a load correct? What pressures for subs are you assuming in your engineering calculations? I know these would be simple questions for an engineer to answer, so thanks in advance for the info.
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OP asked about either standard or decreased tension recoil springs to max reliability when shooting suppressed --not whether he should buy a spring with increased spring tension.

If you "agree" with what Jarvis recommended, why are you dropping a reference to a product you sell with an increased spring tension? Seems a really strained gratuitous product placement.

Assuming OP uses ammo within CIP specs, wouldn't it be best if he does NOT buy your spring and to consider using 197 or subs instead of 198/195--- if his goal is to run suppressed-- like others have noted?

Would welcome seeing your "engineering proof" that a 2lb increase in spring tension does not have an effect on cycling subs. As you claim to be an engineer with multiple degrees, I am sure you are aware of Hooke's Law? You must have run those calculations, no? Spring tension is further dependent on pressure of a load correct? What pressures for subs are you assuming in your engineering calculations? I know these would be simple questions for an engineer to answer, so thanks in advance for the info.
You sound like a disgruntled ex-gf. Douche it out at home and let’s move on. You bring quite a large bag of **** when you start posting. I’m not saying your full of ****, but you are literally ****ting in all the fiveseven threads.
Sorry if the following will disappoint, but I don't engage in ad hominen or name calling.

Claims of engineering expertise (including, but not limited to, multiple degrees) have been made. Let's see if they are ever supported by the person making them.

Constant attempted deflection involving name calling by various profiles is curious. If I were a fan of a multi-degreed engineer vendor, I would welcome and encourage him to share his credential and to provide details to support his claims to expertise. I would also welcome answers supporting the scientific basis for any claim such an engineer might make. I would not engage in name calling to deflect away from, and derail, routine things like those which are very easy things for an expert to provide. After all, why would any expert want to avoid being specific about the basis of his expertise, or refuse to provide the scientific basis for one of his engineering conclusion?

But that's just me....
Trying to act like the bigger person because you don’t stoop to the levels of immaturity similar to name callers, like myself, while lacking the presence of mind to realize that implying that I may be a “fan” is a bit hypocritical. The text in your posts seem to come from a person of maturity and rationale but continuing to spew out that same rhetoric over and over shows a lack of emotional maturity.

Create a thread. Say your piece. Get closure.
You sound like a disgruntled ex-gf. Douche it out at home and let’s move on. You bring quite a large bag of ** when you start posting. I’m not saying your full of **, but you are literally ****ting in all the fiveseven threads.
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JChura
Final warning Your! Trolling behavior is not allowed on fnforum.net
this is very accurate regarding hearing safe. The tone also effects everyone differently. Exposing my ears to in laws constantly asking ****ing questions they’ve already settled on in their heads over and over again because they’re hoping for an answer from me to justify their idiocy has wreaked havoc to my ear drums!

Dead serious…my tinnitus is normally aggravating but when the in laws are here my ear dreams are screaming at the top of their lungs. The acute high pitched ringing from my tympanic membrane develops a deeper but louder noise that sounds like “SHUT THE **** UP!!!!” Over and over again.

my in laws are visiting this weekend for a few days. Super excited.

and also look into the dead air mask

Agreed, with only 10% hearing in my right ear I have re defined hearing safe. I have very nice electronic muffs but I still wear foam plugs under it. Hearing damage is progressive and add to it aging. It all adds up over time so something that is hearing safe for a twenty something vs someone like me who was in Tanks can take out more of what little hearing I have left.

Inlaws. Well My only living one lives with us but she is cool. Blood pressure increasing though can make your tinnitus get worse. Mine's really bad in my right ear. Supposedly there are new hi tech hearing aids, I just had mine tested again as a precursor to attempt to get into a clinical trial that injects a type of stem cell into your ear causing the hairs to grow back, that will after about 3 months of use make it go away since it's a phantom noise. They cost thousands of dollars and I just don't have the scratch sitting around with all the BBB going on.


Here is the info, VA won't do ****e since they classify hearing loss as a Tanker normal .
https://www.clarahealth.com/studies/NCT05086276?query=FX 322&filters=e30=

More info Progenitor Cells | Degnerative Diseases | Frequency Therapeutics





On a side note I blocked JChura so I don't see his posts. It's seems he is still at it.
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Oh the joys of aging…by chance would you be able to throw low pro irons on an mrd?
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Thanks for the replies, y'all. I will reply in detail asap. Real quick: got the Jarvis barrel today!! Didn't expect 'til 'morrow....I will post some pics later as well. Thanks!
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Oh the joys of aging…by chance would you be able to throw low pro irons on an mrd?
I only have them made in Fiber Optic or NS. Once you go Fiber Optic you never go back LOL. That said ALL of our sights work on the MRD.
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