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5/29/2025 10:28:14 AM EDT
[#1]
Quote History
Originally Posted By Roadblock:
Only reason I bought the SPEAR was because I thought we were getting 6.5CM barrels soon-ish.

I gave up, started a LMT 6.5CM build.

View Quote


I've officially timed out waiting for a 6.5 Creedmoor SPEAR release.
5/29/2025 11:38:32 AM EDT
[Last Edit: thehun06][Edited] [#2]
They do need to release ... even though I do not care for 6.5CM ... there are many that do and it would be a great platform to do it on ...

5/29/2025 2:50:06 PM EDT
[#3]
It makes no sense, they already have the tooling for the barrels too. They've already made 6.5CM spears and just decided to not produce them for the mass market for whatever reason. They made like 400 of them and sold them to employees with certificates like some sort of special edition release.
5/29/2025 3:28:29 PM EDT
[#4]
Quote History
Originally Posted By Iccirrus:
It makes no sense, they already have the tooling for the barrels too. They've already made 6.5CM spears and just decided to not produce them for the mass market for whatever reason. They made like 400 of them and sold them to employees with certificates like some sort of special edition release.
View Quote


That’s lame …
5/29/2025 5:53:41 PM EDT
[#5]
Quote History
Originally Posted By thehun06:


That’s lame …
View Quote


No kidding. The weird thing is that the 6.5 is what they had us shooting at freedom days a few years ago, not even the 308
5/30/2025 9:55:34 PM EDT
[Last Edit: Roadblock][Edited] [#6]
I'm salty, I really wanted to get a 16" 6.5CM and chop it to 14.5" p/w. It's OK, LMT build is fun. I really do hope SIG at least releases the update rails soon.

PICTURE REQUEST!

Does anyone have a Samson SAS stock on a SPEAR? I'd love to see a few different picture of one open, folded, extended, collapsed etc.


6/3/2025 6:02:11 PM EDT
[#7]
I really do want someone to release an adjustable gas plug ...
6/4/2025 1:48:08 PM EDT
[Last Edit: thehun06][Edited] [#8]
Well. Talked to my gunsmith. We may go down the road of threading the gas block and using SCAR jets to control gas with traditional cans … or to thread the gas valve to use the jets to have a controlled vent …
6/4/2025 8:16:28 PM EDT
[Last Edit: Roadblock][Edited] [#9]
Quote History
Originally Posted By thehun06:
Well. Talked to my gunsmith. We may go down the road of threading the gas block and using SCAR jets to control gas with traditional cans   or to thread the gas valve to use the jets to have a controlled vent  
View Quote

The guy who makes the Omega valve for the 556 said he has the 308 on his list over on Spear LT thread, just no ETA.
6/4/2025 10:46:06 PM EDT
[#10]
Quote History
Originally Posted By Roadblock:

The guy who makes the Omega valve for the 556 said he has the 308 on his list over on Spear LT thread, just no ETA.
View Quote View All Quotes
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Quote History
Originally Posted By Roadblock:
Originally Posted By thehun06:
Well. Talked to my gunsmith. We may go down the road of threading the gas block and using SCAR jets to control gas with traditional cans   or to thread the gas valve to use the jets to have a controlled vent  

The guy who makes the Omega valve for the 556 said he has the 308 on his list over on Spear LT thread, just no ETA.


Yeah. Talked to him briefly. I hope he does come out with one but I want an ETA … I did offer to be a beta tester …
6/8/2025 12:15:17 AM EDT
[#11]
(I'm not sure if it's okay to talk about the 6.8 Spear here...)

Question about MCX-SPEAR(6.8) parts

I discovered that the appearance of the magazine release is different between the 7.62 SPEAR and the 6.8 SPEAR.

Has the shape of the internal protrusion also been changed?

I also heard that the "bumper" has been changed, but what kind of changes have been made?

If you have a 6.8/fury version SPEAR, please show me pictures of these parts.
6/8/2025 8:24:16 AM EDT
[#12]
Quote History
Originally Posted By kyaroto7:
(I'm not sure if it's okay to talk about the 6.8 Spear here...)

Question about MCX-SPEAR(6.8) parts

I discovered that the appearance of the magazine release is different between the 7.62 SPEAR and the 6.8 SPEAR.

Has the shape of the internal protrusion also been changed?

I also heard that the "bumper" has been changed, but what kind of changes have been made?

If you have a 6.8/fury version SPEAR, please show me pictures of these parts.
View Quote


I haven't seen the magazine release being changed ... but the bumper has been changed to a more conical design similar to MCX 5.56/300 (not an exact copy) and the rear profile of the bolt carrier has been changed to match the buffer vs the flat design of the .308 variant ...

IMHO Sig should have incorproated a hydraulic or spring type buffer ...
6/8/2025 9:51:30 AM EDT
[#13]
There is a guy who makes one for the MCX. Maybe he will make one for the Spear.
link
6/8/2025 2:04:44 PM EDT
[#14]
Quote History
Originally Posted By swar15:
There is a guy who makes one for the MCX. Maybe he will make one for the Spear.
link
View Quote


Yeah. I’ve talked to him. He said more things on the horizon but no ETA or real confirmation.
6/8/2025 8:33:35 PM EDT
[Last Edit: kyaroto7][Edited] [#15]
Quote History
Originally Posted By thehun06:


I haven't seen the magazine release being changed ... but the bumper has been changed to a more conical design similar to MCX 5.56/300 (not an exact copy) and the rear profile of the bolt carrier has been changed to match the buffer vs the flat design of the .308 variant ...

IMHO Sig should have incorproated a hydraulic or spring type buffer ...
View Quote



Thank you for your reply.
When I look at the 6.8 Spear's magazine catch (also for the XM7), there is a slit in the center, so I think that the internal protrusion may have been changed to prevent over-insertion of the magazine, or to accommodate SIG steel magazines.

I've seen the 7.62 Spear's bumper (black, similar to the standard MCX), but the structure itself doesn't seem to have changed much for the 6.8... (I was also hoping for a hydraulic or spring...)
6/8/2025 8:36:51 PM EDT
[#16]
Quote History
Originally Posted By kyaroto7:



Thank you for your reply.
When I look at the 6.8 Spear's magazine catch (also for the XM7), there is a slit in the center, so I think that the internal protrusion may have been changed to prevent over-insertion of the magazine, or to accommodate SIG steel magazines.

I've seen the 7.62 Spear's bumper (black, similar to the standard MCX), but the structure itself doesn't seem to have changed much for the 6.8... (I was also hoping for a hydraulic or spring...)
View Quote


The 6.8 gun I looked at def had a different buffer design …
6/8/2025 8:54:59 PM EDT
[#17]
Quote History
Originally Posted By thehun06:


The 6.8 gun I looked at def had a different buffer design …
View Quote



Oh, is that really true?!
I would love to know more about the 6.8 Spear's magazine release and the new bumper, but SIG won't start selling the parts separately yet...
6/10/2025 11:17:35 AM EDT
[#18]
My gas plug is at the gunsmith to get vented … it will get drilled at the front to accept SCAR jets … I’ll be testing with a 1.2mm and 1.35mm initially for my .308 Spear.

Will report back once tested. This gun is just too overgassed with traditional baffle cans from the factory by a good factor.  

May offer this service to other Spear owners down the road …
6/19/2025 9:55:45 PM EDT
[#19]
Quote History
Originally Posted By thehun06:
My gas plug is at the gunsmith to get vented   it will get drilled at the front to accept SCAR jets   I'll be testing with a 1.2mm and 1.35mm initially for my .308 Spear.

Will report back once tested. This gun is just too overgassed with traditional baffle cans from the factory by a good factor.  

May offer this service to other Spear owners down the road  
View Quote

Curious to hear how it works out.
6/19/2025 10:20:17 PM EDT
[#20]
Will keep you all posted!

Got a new optic setup that needs to be sighted as well.

Poor Man’s DAGR: 2-12 MSR with a piggy back Romeo 5 Gen 2

6/30/2025 6:17:15 AM EDT
[#21]
The gun has been ordered, the model has been drawn, and the prototypes are enroute. Four positions, patent pending threaded vent orifice to accept the PMM screws as well as my own screws that will be available like, this week, with sizes all the way down to 0.50mm. It may be done already, just need to try it out and make sure it works as desired and is, of course, safe to use :)

ETA, as soon as August, no later than Christmas.
6/30/2025 6:19:32 AM EDT
[#22]
Quote History
Originally Posted By Roadblock:

The guy who makes the Omega valve for the 556 said he has the 308 on his list over on Spear LT thread, just no ETA.
View Quote


See my above response :)
6/30/2025 6:22:36 AM EDT
[#23]
Quote History
Originally Posted By swar15:
There is a guy who makes one for the MCX. Maybe he will make one for the Spear.
link
View Quote



Not maybe, it's happening. Very soon. Might even be done already.
6/30/2025 6:39:09 AM EDT
[Last Edit: jbdDesigns][Edited] [#24]
Quote History
Originally Posted By thehun06:


Yeah. I’ve talked to him. He said more things on the horizon but no ETA or real confirmation.
View Quote


Also, I do want to say that I do appreciate everyone's patience. This is almost entirely a solo effort that is pretty much built upon a foundation of pinching pennies to build an MCX from parts and buying a bunch of silencers on Form 4's to test with... which graduated to pinching pennies to buy a factory LT, and now, thanks to everyone's support in the smaller frame world, being able to buy the thicc 308 and two additional silencers to test with. It's thanks to one customer in particular that let me borrow his 308 barrel a few weeks ago to take measurements and test fit plastic models that I'm able to bring the OMEGA Valve Mod. 3 to market as soon as I will be. It's thanks to him that it may be done already, pending a function and safety evaluation.

This thing will completely change the game for the large frame MCX platform, and frankly, the SCAR bros are gonna be jealous. Four positions, patent pending slotted port geometry and threaded vent orifice technology. Between PMM's 17 screws and the 7 that I will be offering (for now), there will be over 100 repeatable ways to dial in your system.

I also appreciate the willingness and desire of you and the several others that have offered to beta test my designs. The thing is, there is no beta testing needed, the concept is proven. It's now a matter of desirable functionality (which I have the means to determine on my own), and a matter of safety, which for obvious reasons I will test myself.
7/1/2025 11:13:30 AM EDT
[Last Edit: thehun06][Edited] [#25]
Quote History
Originally Posted By jbdDesigns:


Also, I do want to say that I do appreciate everyone's patience. This is almost entirely a solo effort that is pretty much built upon a foundation of pinching pennies to build an MCX from parts and buying a bunch of silencers on Form 4's to test with... which graduated to pinching pennies to buy a factory LT, and now, thanks to everyone's support in the smaller frame world, being able to buy the thicc 308 and two additional silencers to test with. It's thanks to one customer in particular that let me borrow his 308 barrel a few weeks ago to take measurements and test fit plastic models that I'm able to bring the OMEGA Valve Mod. 3 to market as soon as I will be. It's thanks to him that it may be done already, pending a function and safety evaluation.

This thing will completely change the game for the large frame MCX platform, and frankly, the SCAR bros are gonna be jealous. Four positions, patent pending slotted port geometry and threaded vent orifice technology. Between PMM's 17 screws and the 7 that I will be offering (for now), there will be over 100 repeatable ways to dial in your system.

I also appreciate the willingness and desire of you and the several others that have offered to beta test my designs. The thing is, there is no beta testing needed, the concept is proven. It's now a matter of desirable functionality (which I have the means to determine on my own), and a matter of safety, which for obvious reasons I will test myself.
View Quote View All Quotes
View All Quotes
Quote History
Originally Posted By jbdDesigns:
Originally Posted By thehun06:


Yeah. I’ve talked to him. He said more things on the horizon but no ETA or real confirmation.


Also, I do want to say that I do appreciate everyone's patience. This is almost entirely a solo effort that is pretty much built upon a foundation of pinching pennies to build an MCX from parts and buying a bunch of silencers on Form 4's to test with... which graduated to pinching pennies to buy a factory LT, and now, thanks to everyone's support in the smaller frame world, being able to buy the thicc 308 and two additional silencers to test with. It's thanks to one customer in particular that let me borrow his 308 barrel a few weeks ago to take measurements and test fit plastic models that I'm able to bring the OMEGA Valve Mod. 3 to market as soon as I will be. It's thanks to him that it may be done already, pending a function and safety evaluation.

This thing will completely change the game for the large frame MCX platform, and frankly, the SCAR bros are gonna be jealous. Four positions, patent pending slotted port geometry and threaded vent orifice technology. Between PMM's 17 screws and the 7 that I will be offering (for now), there will be over 100 repeatable ways to dial in your system.

I also appreciate the willingness and desire of you and the several others that have offered to beta test my designs. The thing is, there is no beta testing needed, the concept is proven. It's now a matter of desirable functionality (which I have the means to determine on my own), and a matter of safety, which for obvious reasons I will test myself.


I simply cannot wait ... it needs it so bad ... that said I do have my OEM plug getting worked on for venting but I will still more than likely pick up your plug
7/1/2025 12:53:17 PM EDT
[#26]
Quote History
Originally Posted By thehun06:


I simply cannot wait ... it needs it so bad ... that said I do have my OEM plug getting worked on for venting but I will still more than likely pick up your plug
View Quote

I appreciate the support, and hey, I get it. The 5.56 gun had a lot of room for improvement, I can only imagine what y'all are dealing with with the big guns. I aim to make the thing one of the most enjoyable, softest shooting 308s on the market. Out of curiosity, what barrel lengths are we running? I ordered a 13" pistol so I can freely convert it back and forth all willy nilly without dealing with any NFA shenanigans. Also short guns are the coolest.
7/1/2025 1:45:55 PM EDT
[#27]
Quote History
Originally Posted By jbdDesigns:

I appreciate the support, and hey, I get it. The 5.56 gun had a lot of room for improvement, I can only imagine what y'all are dealing with with the big guns. I aim to make the thing one of the most enjoyable, softest shooting 308s on the market. Out of curiosity, what barrel lengths are we running? I ordered a 13" pistol so I can freely convert it back and forth all willy nilly without dealing with any NFA shenanigans. Also short guns are the coolest.
View Quote View All Quotes
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Quote History
Originally Posted By jbdDesigns:
Originally Posted By thehun06:


I simply cannot wait ... it needs it so bad ... that said I do have my OEM plug getting worked on for venting but I will still more than likely pick up your plug

I appreciate the support, and hey, I get it. The 5.56 gun had a lot of room for improvement, I can only imagine what y'all are dealing with with the big guns. I aim to make the thing one of the most enjoyable, softest shooting 308s on the market. Out of curiosity, what barrel lengths are we running? I ordered a 13" pistol so I can freely convert it back and forth all willy nilly without dealing with any NFA shenanigans. Also short guns are the coolest.


I will say 50/50 from what I’ve seen.

13” guns seem to be gassed better than 16” …
7/1/2025 3:01:30 PM EDT
[#28]
Quote History
Originally Posted By thehun06:


I will say 50/50 from what I’ve seen.

13” guns seem to be gassed better than 16” …
View Quote

Shorter dwell time, the longer barrel should be technically more reliable, but also more hateful on the gas operation. Sweet. Both shall be tested.

Also, I saw a bunch of you guys asking about the 6.5, I swear I saw one on GB for like, an absurd amount of money, like $6K or so. Idk, I guess they exist?
7/1/2025 3:25:13 PM EDT
[#29]
Quote History
Originally Posted By jbdDesigns:

Shorter dwell time, the longer barrel should be technically more reliable, but also more hateful on the gas operation. Sweet. Both shall be tested.

Also, I saw a bunch of you guys asking about the 6.5, I swear I saw one on GB for like, an absurd amount of money, like $6K or so. Idk, I guess they exist?
View Quote View All Quotes
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Quote History
Originally Posted By jbdDesigns:
Originally Posted By thehun06:


I will say 50/50 from what I’ve seen.

13” guns seem to be gassed better than 16” …

Shorter dwell time, the longer barrel should be technically more reliable, but also more hateful on the gas operation. Sweet. Both shall be tested.

Also, I saw a bunch of you guys asking about the 6.5, I swear I saw one on GB for like, an absurd amount of money, like $6K or so. Idk, I guess they exist?


Prototype 6.5 I believe …

Yeah the 16” guns are veeeeeery over gassed with a traditional can.
7/1/2025 11:48:13 PM EDT
[Last Edit: Roadblock][Edited] [#30]
Quote History
Originally Posted By thehun06:


Prototype 6.5 I believe  

Yeah the 16" guns are veeeeeery over gassed with a traditional can.
View Quote View All Quotes
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Quote History
Originally Posted By thehun06:
Originally Posted By jbdDesigns:
Originally Posted By thehun06:


I will say 50/50 from what I've seen.

13" guns seem to be gassed better than 16"  

Shorter dwell time, the longer barrel should be technically more reliable, but also more hateful on the gas operation. Sweet. Both shall be tested.

Also, I saw a bunch of you guys asking about the 6.5, I swear I saw one on GB for like, an absurd amount of money, like $6K or so. Idk, I guess they exist?


Prototype 6.5 I believe  

Yeah the 16" guns are veeeeeery over gassed with a traditional can.

I'm running the 16" 308. I feel like SIG has probably sold more 16" 308's than 13".

Aesthetically speaking I think the 13" SBR is damn sexy but it just didn't make sense for me. If I'm going 308/6.5CM I want 16" or bigger. If I need something small I have an 11.5" LT, 11.5" URGI and case of M855A1.

I have shot the 13" 308 though, it's much less gassy than my 16".

SIG made about 140 or so 16" 6.5CM rifles. They were sold off in a private sale to employees and to friends of the company.

Supposedly they are going to release a 6.5CM barrel, someday, if enough people bitch. The .277/6.8x51 just seems like such a flop other than Big Army and you two or three cloners but I would have loved a 6.5CM barrel.
7/2/2025 1:14:13 PM EDT
[#31]
Quote History
Originally Posted By Roadblock:

I'm running the 16" 308. I feel like SIG has probably sold more 16" 308's than 13".

Aesthetically speaking I think the 13" SBR is damn sexy but it just didn't make sense for me. If I'm going 308/6.5CM I want 16" or bigger. If I need something small I have an 11.5" LT, 11.5" URGI and case of M855A1.

I have shot the 13" 308 though, it's much less gassy than my 16".

SIG made about 140 or so 16" 6.5CM rifles. They were sold off in a private sale to employees and to friends of the company.

Supposedly they are going to release a 6.5CM barrel, someday, if enough people bitch. The .277/6.8x51 just seems like such a flop other than Big Army and you two or three cloners but I would have loved a 6.5CM barrel.
View Quote

That would explain the high price tag I saw.

Regarding the 16" vs 13", one of the reasons I liked focusing on the shorter of the 5.56 barrels was because if they didn't have separate valves for each length, that shorter dwell time would tend to -at least to some degree- lend itself to a less reliable system. The basic thought process is if I can get the shorter barrel to do everything that I want it to do reliably, there shouldn't be any reason that the same OMEGA Valve can't be adjusted to work with the longer dwell time of the longer barrel. Naturally, I will confirm this :)

I can't even tell you guys how stoked I am. Everyone's all hyped up for my 300BLK valve, but it's the 5.56 and 308 that need the most help.
7/2/2025 1:17:49 PM EDT
[#32]
Quote History
Originally Posted By thehun06:


Prototype 6.5 I believe …

Yeah the 16” guns are veeeeeery over gassed with a traditional can.
View Quote

You know, it's interesting. I had already finished my Mod. 2-S valve (300BLK, shorter barrels), and I decided to use a recessed, tapered gas port to enhance the reliability of the system with subsonic ammo and short dwell time in the barrel.

When a customer sent me his 16" 308 barrel to take some preliminary measurements and such, I was kinda shocked to find that the valve that comes with these guns has recessed tapered gas ports. Like, no wonder you guys are suffering.
7/2/2025 5:33:33 PM EDT
[#33]
Quote History
Originally Posted By jbdDesigns:

You know, it's interesting. I had already finished my Mod. 2-S valve (300BLK, shorter barrels), and I decided to use a recessed, tapered gas port to enhance the reliability of the system with subsonic ammo and short dwell time in the barrel.

When a customer sent me his 16" 308 barrel to take some preliminary measurements and such, I was kinda shocked to find that the valve that comes with these guns has recessed tapered gas ports. Like, no wonder you guys are suffering.
View Quote


Yeah man. It sucks with a traditional can …
7/3/2025 2:50:12 AM EDT
[#34]
Remember that Raptor from 3 years ago? Anything new on that since then? I haven't paid much attention. Fury version would be pretty cool imo
7/3/2025 8:42:23 AM EDT
[#35]
Quote History
Originally Posted By GrAvril:
Remember that Raptor from 3 years ago? Anything new on that since then? I haven't paid much attention. Fury version would be pretty cool imo
View Quote


No ...
7/3/2025 9:58:22 AM EDT
[#36]
Quote History
Originally Posted By thehun06:


No ...
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Quote History
Originally Posted By thehun06:
Originally Posted By GrAvril:
Remember that Raptor from 3 years ago? Anything new on that since then? I haven't paid much attention. Fury version would be pretty cool imo


No ...


Betting SIG is a bit busy on the military contract and fixing production issues that crop up, to work on other configurations of the Spear.

Hell they still haven't offered the updated handguard separately yet.
7/3/2025 11:39:53 AM EDT
[#37]
And the .277 conversion…
7/18/2025 9:12:49 PM EDT
[#38]
Upgraded my optics from a lowly T1.

Attached File
What a long strange trip it's been...
7/19/2025 9:12:12 AM EDT
[#39]
Well. Trying this out as a DMR … no range time yet but new 2-12x44 Sig optic is punching well above its price point.

My example is very accurate and fits this role quite well, scale comes in at 12lbs 1 oz.

Attached File
7/22/2025 9:43:45 PM EDT
[Last Edit: SuperMoose][Edited] [#40]
Alright...having issues with my SPEAR (Factory SBR).

Zeroed it yesterday and had a few of these malfunctions. More tonight.

Shooting PPU 145gr FMJ. Dead Air Sandman-K on the end and the gas was switched to the suppressed mode. Gen3 PMAGs are being used.

The gun isn't reliably extracting spent rounds and is feeding another round into the back of the unextracted round. To make matters worse, the problem is intermittent. Sometimes it's every two rounds, sometimes I can get a few more off before it happens again.

This evening I had several cases that the rim on the side was sheared clean off and I had to use a rod to tap out the brass. Last round of the night (took the silencer off and switched the gas to normal) resulted in a round stuck in the chamber and ultimately a bullet lodged in the barrel (I tapped it out when I got home).

I don't really have any other 308 other than some expensive Black Hills stuff. I presume the answer is to try some other ammo? Anything else I should look at?

I'm going to be a little annoyed if it's the ammo, only because I have a bunch of this PPU sitting around...and I sold my SCAR which shot it just fine...


ETA: cleaned it this morning to take it back out and see if that solved anything.

What are the barrel screws supposed to be torqued to? 60 in-lbs? 40 in-lbs? I want to check those too.

ETA: Pictures from this morning

Had several failure to feeds (all looked like this).

Failure to feed





Damage to the round



Gas Setting



Failure to extract



Also had a failure to lock the bolt open on last round of the mag (fired and ejected)
What a long strange trip it's been...
7/23/2025 9:05:27 AM EDT
[Last Edit: thehun06][Edited] [#41]
Quote History
Originally Posted By SuperMoose:
Alright...having issues with my SPEAR (Factory SBR).

Zeroed it yesterday and had a few of these malfunctions. More tonight.

Shooting PPU 145gr FMJ. Dead Air Sandman-K on the end and the gas was switched to the suppressed mode. Gen3 PMAGs are being used.

The gun isn't reliably extracting spent rounds and is feeding another round into the back of the unextracted round. To make matters worse, the problem is intermittent. Sometimes it's every two rounds, sometimes I can get a few more off before it happens again.

This evening I had several cases that the rim on the side was sheared clean off and I had to use a rod to tap out the brass. Last round of the night (took the silencer off and switched the gas to normal) resulted in a round stuck in the chamber and ultimately a bullet lodged in the barrel (I tapped it out when I got home).

I don't really have any other 308 other than some expensive Black Hills stuff. I presume the answer is to try some other ammo? Anything else I should look at?

I'm going to be a little annoyed if it's the ammo, only because I have a bunch of this PPU sitting around...and I sold my SCAR which shot it just fine...


ETA: cleaned it this morning to take it back out and see if that solved anything.

What are the barrel screws supposed to be torqued to? 60 in-lbs? 40 in-lbs? I want to check those too.
View Quote


I had the same issue with some Igman ammo ... for one they were loaded hot compared to Federal 7.62x51 creating severe overgassing and two it has soft brass ... I had to tap out some rounds ...

Switched back to Federal and Aguila ball ... no issues ...

I believe you are experiencing what I experienced ...

I run 55 in/lbs on barrel screws or MCX platforms and 35 in/lbs for MPX ... OEM recommendation is 60. MAKE sure that your barrel is full seated rearward prior to torqueing down the clamps ...
7/23/2025 10:24:46 AM EDT
[#42]
Quote History
Originally Posted By thehun06:


I had the same issue with some Igman ammo ... for one they were loaded hot compared to Federal 7.62x51 creating severe overgassing and two it has soft brass ... I had to tap out some rounds ...

Switched back to Federal and Aguila ball ... no issues ...

I believe you are experiencing what I experienced ...

I run 55 in/lbs on barrel screws or MCX platforms and 35 in/lbs for MPX ... OEM recommendation is 60. MAKE sure that your barrel is full seated rearward prior to torqueing down the clamps ...
View Quote


That's not what I want to hear re: ammo... I have a bunch of this in the basement.

I presume, if someone made a smaller sized gas port, if it is overgassed, that would solve the issue?
What a long strange trip it's been...
7/23/2025 10:46:10 AM EDT
[Last Edit: thehun06][Edited] [#43]
Quote History
Originally Posted By SuperMoose:


That's not what I want to hear re: ammo... I have a bunch of this in the basement.

I presume, if someone made a smaller sized gas port, if it is overgassed, that would solve the issue?
View Quote View All Quotes
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Quote History
Originally Posted By SuperMoose:
Originally Posted By thehun06:


I had the same issue with some Igman ammo ... for one they were loaded hot compared to Federal 7.62x51 creating severe overgassing and two it has soft brass ... I had to tap out some rounds ...

Switched back to Federal and Aguila ball ... no issues ...

I believe you are experiencing what I experienced ...

I run 55 in/lbs on barrel screws or MCX platforms and 35 in/lbs for MPX ... OEM recommendation is 60. MAKE sure that your barrel is full seated rearward prior to torqueing down the clamps ...


That's not what I want to hear re: ammo... I have a bunch of this in the basement.

I presume, if someone made a smaller sized gas port, if it is overgassed, that would solve the issue?


Yeah ... Bennett Designs is making one ... I have my gas plug at my gunsmith to thread it for scar jets so I can vent excess gas ... you have to remember that the OEM supppresor gas tuning is based on Sig's suppressor ... traditional baffled cans will be overgassed ... couple that with ammo that is loaded hotter than normal ... and you get the reliability hit ... I would guess if you take the can off ... your issues would go away to some degree ... but PPU is known for soft brass and you can have ripped cases with it.
7/23/2025 10:08:13 PM EDT
[Last Edit: Roadblock][Edited] [#44]
I would suggest getting a couple factory Spear factory magazines as well as a couple Lancers.

I have had a lot of issues with PMAG's, especially the 10 round magazines but have also had it with several 20's.

Exact same thing you are seeing but switching to Lancers pretty much fixed it. Bought a couple factory Spear magazines also and they seem to run flawlessly with all the ammo I've tried too.


7/23/2025 10:19:08 PM EDT
[#45]
Quote History
Originally Posted By Roadblock:
I would suggest getting a couple factory Spear factory magazines as well as a couple Lancers.

I have had a lot of issues with PMAG's, especially the 10 round magazines but have also had it with several 20's.

Exact same thing you are seeing but switching to Lancers pretty much fixed it. Bought a couple factory Spear magazines also and they seem to run flawlessly with all the ammo I've tried too.


View Quote


There is no factory .308 magazine from Sig. They do offer one for the 6.8 …

But his issue isn’t mag related …
7/24/2025 6:41:10 AM EDT
[#46]
Quote History
Originally Posted By thehun06:


There is no factory .308 magazine from Sig. They do offer one for the 6.8 …

But his issue isn’t mag related …
View Quote


I was going to say...SIG shipped it with PMAGs.

I was digging through my ammo and found some other 308 that I'll try but unfortunately I only have two boxes of it.
What a long strange trip it's been...
7/24/2025 12:28:37 PM EDT
[#47]
Quote History
Originally Posted By SuperMoose:


I was going to say...SIG shipped it with PMAGs.

I was digging through my ammo and found some other 308 that I'll try but unfortunately I only have two boxes of it.
View Quote View All Quotes
View All Quotes
Quote History
Originally Posted By SuperMoose:
Originally Posted By thehun06:


There is no factory .308 magazine from Sig. They do offer one for the 6.8 …

But his issue isn’t mag related …


I was going to say...SIG shipped it with PMAGs.

I was digging through my ammo and found some other 308 that I'll try but unfortunately I only have two boxes of it.


Fire some without the can on ... in unsuppressed setting ... see what it does ... even with PPU
7/29/2025 11:29:41 AM EDT
[#48]
Got my plug back and installed a 1.15mm SCAR jet.

I am hoping to test this weekend.

Attached File
7/30/2025 12:17:18 PM EDT
[#49]
Got a couple of prototypes in :) No shots yet and I need to adjust the indexing lug to make it easier to turn by hand, but damn does it look good. Shooting as soon as possible, hopefully tomorrow morning if I can swing it.
7/30/2025 6:55:24 PM EDT
[#50]
I'll be excited to hear your results as well ... one way or another I will tame this beast down with a traditional can

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