Mbx lightweight barrel

[CalTeacher]

I’ve shot 2” groups with 124gr jhp from my 14.5”  barrel and holosun 510c at 70yds.  It doesn’t take bullets with a long bearing surface to shoot good groups from these guns.  Jacketed round nose bullets don’t shoot as well as jhp because of the base, but they should still group within an inch at 25yds.

 

The barrel here isn’t the problem.  It’s either the load, shooter, or optic.

[Mac-pcc]

52 minutes ago, CalTeacher said:

 

The barrel here isn’t the problem.  It’s either the load, shooter, or optic.

 If that were the case how would three different people with the same barrel have the same issue? It would seem like the common denominator is the barrels. 

[CalTeacher]

The barrel didn’t experience the same issue when tested at MBX.

 

[Mac-pcc]

 From the pics that is correct but what we don't know is if any work was done on the barrels before those groups were shot.

[Mac-pcc]

 All I'm saying is we don't know and it's all speculation at this point.  I'm sure its probably a limited number that have the issue and that they will resolve the problem.  From what I understand MBX is a stand up company.  I've never had any issues with any of the products that I have of theirs.

[MemphisMechanic]

4 minutes ago, CalTeacher said:

The barrel didn’t experience the same issue when tested at MBX.

 

 

I’ve watched one of the guys in question shoot damn near a 1-hole group with a 5.56 at 100yd.

 

The same 9mm ammo shot about 1.5” through a JP barrel, and won’t break 5” through the MBX.

[MemphisMechanic]

8 minutes ago, Mac-pcc said:

 All I'm saying is we don't know and it's all speculation at this point.  I'm sure its probably a limited number that have the issue and that they will resolve the problem.  From what I understand MBX is a stand up company.  I've never had any issues with any of the products that I have of theirs.

 

It’s kinda hard to paint you as an MBX hater with a mediumweight barrel in your gun and their extensions on all your mags.

 

Edited December 22, 2018 by MemphisMechanic

[Mac-pcc]

1 minute ago, MemphisMechanic said:

 

It’s kinda hard to paint you as an MBX hater with a mediumweight barrel in your gun and their extensions on all your mags.

 

I'm definitely not. As a matter of fact the reason that all the guys in question bought the barrels is because of me and the good experience I have had with my MBX stuff. 

[blckout]

19 minutes ago, Mac-pcc said:

I'm definitely not. As a matter of fact the reason that all the guys in question bought the barrels is because of me and the good experience I have had with my MBX stuff. 

Truth.

I do not know what voodoo they are doing to get the drastic different results that we are all getting.

My build Is a QC10 upper and lower, JP enhanced bolt, JP short stroke SCS.

[CalTeacher]

35 minutes ago, MemphisMechanic said:

 

I’ve watched one of the guys in question shoot damn near a 1-hole group with a 5.56 at 100yd.

 

The same 9mm ammo shot about 1.5” through a JP barrel, and won’t break 5” through the MBX.

Then maybe that load sucks through the MBX.  

[blckout]

2 minutes ago, CalTeacher said:

Then maybe that load sucks through the MBX.  

I shot 4 different factory rounds.

 

Optic is a Holosun 510c.  

[CalTeacher]

9 minutes ago, blckout said:

I shot 4 different factory rounds.

 

Optic is a Holosun 510c.  

Well then maybe it’s voodoo.  I can’t say what caused this, but why isn’t it happening with the testing done by MBX?

 

Do you think MBX could have fudged the results of their test?

[blckout]

2 minutes ago, CalTeacher said:

Well then maybe it’s voodoo.  I can’t say what caused this, but why isn’t it happening with the testing done by MBX?

 

Do you think MBX could have fudged the results of their test?

I really don't think the would have fudged them.  I don't know them very well but many many have done a lot of business with them and they seems to be very reputable.  

I just would really like to know what they are doing different.  It is not a difficult process.  If it was some gun tuning issue, where there was a variable that we 3 are getting wrong then cool.  But its 3 pieces.  Barrel, Rail, and Upper.

[MoRivera]

Could it have something to do with the BCG?

[MemphisMechanic]

2 hours ago, MoRivera said:

Could it have something to do with the BCG?

 

Explain a barrel change in all three of these guns causing a quadruling in group size... with multiple brands of 115, 124, and 147gr factory ammo, and the same shooter.

[MemphisMechanic]

6 hours ago, CalTeacher said:

Well then maybe it’s voodoo.  I can’t say what caused this, but why isn’t it happening with the testing done by MBX?

 

Do you think MBX could have fudged the results of their test?

 

Again: Explain a barrel change in all three of these guns causing a quadruling in group size... with multiple brands of 115, 124, and 147gr factory ammo, and the same shooter.

 

It is not impossible that MBX is being less than straightforward with the test results. It’s not something I think is likely, but they do have a lot of reputation and money at stake here.

 

I do have to say that their customer contact attitude with my friends has certainly left me disinclined to buy anything they make at this point.

 

Emailing your customers back after half a week of sending repeared emails... and then coming back with phrases like “the supposed accuracy issues with your barrel” leaves a very great deal to be desired.

 

Edited December 22, 2018 by MemphisMechanic

[Stymie12000]

3 hours ago, MemphisMechanic said:

 

Again: Explain a barrel change in all three of these guns causing a quadruling in group size... with multiple brands of 115, 124, and 147gr factory ammo, and the same shooter.

 

It is not impossible that MBX is being less than straightforward with the test results. It’s not something I think is likely, but they do have a lot of reputation and money at stake here.

 

I do have to say that their customer contact attitude with my friends has certainly left me disinclined to buy anything they make at this point.

 

Emailing your customers back after half a week of sending repeared emails... and then coming back with phrases like “the supposed accuracy issues with your barrel” leaves a very great deal to be desired.

 

I had a similar experience with MBX on a brand new mag issue.

 

No phone # only email.  After multiple emails sent, I never got a response. Needless to say I won't buy anything other than mag bases from them after this experience. 

[CalTeacher]

Something else to consider is whether taking that much material off the barrel makes it so much less rigid that the barrel can actually vibrate so much to affect accuracy.

 

it would be an interesting test to start with the same barrel blank and accuracy test it in its original, heavy state.  Then, begin turning it on a lathe and reducing weight in increments, testing for accuracy along the way to see if any thing changes, and at what point the changes occur.

[Mac-pcc]

3 minutes ago, CalTeacher said:

Something else to consider is whether taking that much material off the barrel makes it so much less rigid that the barrel can actually vibrate so much to affect accuracy.

 

it would be an interesting test to start with the same barrel blank and accuracy test it in its original, heavy state.  Then, begin turning it on a lathe and reducing weight in increments, testing for accuracy along the way to see if any thing changes, and at what point the changes occur.

 That would be pretty interesting. Could have something to do with it.

[Startingover]

38 minutes ago, CalTeacher said:

Something else to consider is whether taking that much material off the barrel makes it so much less rigid that the barrel can actually vibrate so much to affect accuracy.

 

it would be an interesting test to start with the same barrel blank and accuracy test it in its original, heavy state.  Then, begin turning it on a lathe and reducing weight in increments, testing for accuracy along the way to see if any thing changes, and at what point the changes occur.

I was wondering about these barrels when I found out they are not much heavier than my tension barrel from Taccom.

 

I was asking myself ...

"If Taccom feels like they need a sleeve for support, how can the MBX barrel not act like a wet noodle?"

This might explain that!

 

[MemphisMechanic]

The barrels measure .525 at their thinnest diameter, which is .085” wall thickness.

 

The mediumweight MBX is .625” diameter at its thinnest, which is 37% thicker.

 

I turned my CMMG barrel down to .625” from .750, which took half a pound off of it. It still shoots a tight group.

[blckout]

4 hours ago, Stymie12000 said:

I had a similar experience with MBX on a brand new mag issue.

 

No phone # only email.  After multiple emails sent, I never got a response. Needless to say I won't buy anything other than mag bases from them after this experience. 

 

They sent me an email with the pics from this thread on Wednesday.  I replied that day and am still waiting on a reply.  

 

Their response times are less than stellar. Sitting here with a 300 dollar barrel and waiting days for emai replies.  

 

I went ahead and ordered a JP barrel and comp.  I’ll probably have it before I get an email reply.  

[MoRivera]

9 hours ago, MemphisMechanic said:

 

Explain a barrel change in all three of these guns causing a quadruling in group size... with multiple brands of 115, 124, and 147gr factory ammo, and the same shooter.

I dunno...explain a shooter somehow shooting worse with a barrel change.  Allergic reaction? 

Edited December 22, 2018 by MoRivera

[MoRivera]

4 hours ago, Mac-pcc said:

 That would be pretty interesting. Could have something to do with it.

That's what I mentioned back in my second post.  But if that was the case, could that depend on the stability of the shooter or something?  Whereas if you lock the gun down in a ransom rest or the like, it wouldn't be affected as much?

[Mac-pcc]

6 hours ago, MoRivera said:

That's what I mentioned back in my second post.  But if that was the case, could that depend on the stability of the shooter or something?  Whereas if you lock the gun down in a ransom rest or the like, it wouldn't be affected as much?

That is a interesting thought. But that would stink if it will only shoot well locked down in a rest.