MBX Rock Island Problem

[Steve-O]

So I just got my MBX .40 (P) 140 mm mag in today for my Rock Island Pro Match .40 and alittle disappointed and need help. The gun has been 100% reliable with factory mags and factory ammo, Winchester White Box, Remington UMC ect. The MBX mag over inserts where the feed lip goes up and covers half of the ejector when pushed upwards. When the mag is empty in the gun you can move the mag all around and when shaking the gun it sounds like a kids toy. Also the rounds nose dive 70% of the time. Any help would be appreciated. 

[jcc7x7]

Don't shoot with it and call MBX Monday!

[tomjerry1]

I use only MBX with my Pro 40, but there was a few issues with the MBX mags in the beginning, call them, they will take care of you.

[Steve-O]

Thanks guys I will call them on Monday. 

[Steve-O]

The RI mag catch is not designed to stop the mag same as 99% of  all 2011  guns Dawson made a positive mag catch for STI plastic grip  but not sure if any available for RI that would be your answer if you feel you need a positive catch 
When mag is loaded and slide forward the mag should inset with enough over travel to allow catch to go in and then the bullets with spring pressure keep the mag low enough normally while reloading and seat the mag on the top of the catch .

 

 

This is the email i just got from MBX what do you think? 

Edited May 18, 2019 by Steve-O

[AHI]

Most 2011 style guns have the slide stop deactivated for one reason or another.

Your RI falls in this category. Mags are inserted with the slide closed mostly to prevent 

over insertion .   So when your MBX magazine is inserted with the slide closed does your 

issue go away?

Edited May 18, 2019 by AHI

[Steve-O]

2 hours ago, AHI said:

Most 2011 style guns have the slide stop deactivated for one reason or another.

Your RI falls in this category. Mags are inserted with the slide closed mostly to prevent 

over insertion .   So when your MBX magazine is inserted with the slide closed does your 

issue go away?

With a empty mag it rattles around in the gun, when loaded it doesn’t rattle around but still can be pushed upwards and the rounds nose dive most of the time. 

[jcc7x7]

4 hours ago, Steve-O said:

The RI mag catch is not designed to stop the mag same as 99% of  all 2011  guns Dawson made a positive mag catch for STI plastic grip  but not sure if any available for RI that would be your answer if you feel you need a positive catch 
When mag is loaded and slide forward the mag should inset with enough over travel to allow catch to go in and then the bullets with spring pressure keep the mag low enough normally while reloading and seat the mag on the top of the catch .

 

 

This is the email i just got from MBX what do you think? 

Answers like this is what I got for a Tanfo 170mm mag.

Also the reason I'm not one of their fan boys.

I don't like STI frames or slides for numerous reasons but I do use their mags because If they don't work

I can get them to send me a new one and do minor tuning if needed to have them work perfect.

MBX's whole marketing deal is "competition ready" doesn't sound like they lived up to their own hype!

Ask them to send you a return label and ask them to get their product working correctly. IMO

[Steve-O]

And I don’t think they understand is if Iam doing reload drills the feed lips are going to be banging the ejector everytime. I didn’t have this issue with my STI Edge and STI mags there is definitely something not right here. 

[tomjerry1]

I switched to MBX for this exact reason. If you are using STI, or other mags, I bet you own a Dawson mag tuning kit, or some other tools for tuning you mags, it's not if you will need this, it's when. I have MBX for 40 and 38SC, think I made the switch 4 years ago, to date, haven't put a tool on either. If the mag is hitting the ejector during reloads, that is a disaster waiting to happen. The issue I had with MBX and the Pro 40 was, they sent me the wrong mags? Once I called them, they promptly sent me the correct mags, and I haven't had a problem since. I know it's frustrating, and there are plenty of shoots around the corner, but they will take care of you.

[soulbyte]

I had the same over insertion problem with my Rock Island and STI gen 1 magazines. To correct it I got the dawson posi-lock mag release for STI, which fit in my Rock Island. Also did you get MBX STI or MBX Para magazines? The OEM STI mags fit and work perfect for my frame, same as the Pro Match, which was designed to be able to use the STI magazines.  

Edited June 2, 2019 by soulbyte

[Steve-O]

7 hours ago, soulbyte said:

I had the same over insertion problem with my Rock Island and STI gen 1 magazines. To correct it I got the dawson posi-lock mag release for STI, which fit in my Rock Island. Also did you get MBX STI or MBX Para magazines? The OEM STI mags fit and work perfect for my frame, same as the Pro Match, which was designed to be able to use the STI magazines.  

I have the MBX Para Mag, I will try the posi lock and see what happens. Thanks 

[Steve-O]

Well I installed the Dawson Posi Lock mag release and it fixed the over insertion issue but now the mags won’t drop free and instead of the mag release being flush on the right side now it’s sunken in with the Dawson. Kind of lost on what to do now besides just take it to a gunsmith. 

Edited June 8, 2019 by Steve-O