I looked but cannot find...what 9mm bolts reset a LaRue MBT

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[ARCHIVED THREAD] - I looked but cannot find...what 9mm bolts reset a LaRue MBT

Posted: 1/15/2021 5:30:47 PM EDT

I know KAK and Kaw Valley do not.

I would prefer buying a new bolt as opposed to changing triggers.

Glock mag and Endo mag.

Posted: 1/15/2021 7:22:01 PM EDT

[#1]

Seems like I remember in one discussion about this problem that the 9mm bolt needs to have something welded to build up the ramp and enable the MBT hammer to reset. Might ask Rudy at Macon Armory. I think that he was in on the discussion.

Posted: 1/17/2021 11:48:19 AM EDT

[#2]

I have a MBT-1S that runs flawless on a Spike's Tactical Bolt.

Posted: 1/18/2021 9:39:24 AM EDT

[#3]

I had a Toolcraft bcg that manually reset the LaRue trigger. I never fired it with that setup, but don't see a reason it wouldn't reset.

Posted: 1/18/2021 6:17:18 PM EDT

[#4]

Found a video Rudy made about his fix for using the MBT with 9mm bolts.

https://youtu.be/We2ux7Ip_yY

Posted: 1/18/2021 8:05:08 PM EDT

[#5]

My PSA works fine. It needs to be “ramped” for a standard (not 9mm) hammer.

Posted: 1/18/2021 8:11:32 PM EDT

[#6]

Quote History

Quoted:
Found a video Rudy made about his fix for using the MBT with 9mm bolts.

https://youtu.be/We2ux7Ip_yY

View Quote

Wonder what bolt it is....

Posted: 1/18/2021 8:21:18 PM EDT

[#7]

Quote History

Quoted:
I have a MBT-1S that runs flawless on a Spike's Tactical Bolt.

View Quote

Does look like this one, with the odd ass end?

Attached File

Posted: 1/18/2021 8:45:50 PM EDT

[#8]

@HK_DUDE

I don't remember. I can post a picture tonight when I get home, it'll be kinda late I have a Pool League after work.

Posted: 1/18/2021 8:55:42 PM EDT

[#9]

I appreciate it.

Posted: 1/18/2021 9:00:00 PM EDT

[#10]

min works fine with a faxon bolt.

Posted: 1/18/2021 9:47:19 PM EDT

[#11]

Mbt trigger would not work with spinta bolt

Posted: 1/18/2021 9:52:23 PM EDT

[#12]

Quote History

Quoted:
min works fine with a faxon bolt.

View Quote

I assume your Faxon bolt looks like this one?

Attached File

Posted: 1/18/2021 10:48:00 PM EDT

[#13]

Quote History

Quoted:

I assume your Faxon bolt looks like this one?

https://www.ar15.com/media/mediaFiles/3591/Screenshot_20210118-195057_Chrome_jpg-1785880.JPG

View Quote

yah that looks like it.

just need to make sure the bolt has a good ramp where the hammer would slide along. the earlier versions would have a flat face that would catch the hammer.

Posted: 1/19/2021 12:57:19 AM EDT

[#14]

Quote History

Quoted:

yah that looks like it.

just need to make sure the bolt has a good ramp where the hammer would slide along. the earlier versions would have a flat face that would catch the hammer.

View Quote

To make it work, you need to do a build up just in front of the ramp.....add .040 and then blend into the ramp and front flat and polish with Cratex

Posted: 1/19/2021 12:59:51 AM EDT

[#15]

Thank you all.

Posted: 1/19/2021 6:10:12 PM EDT

[#16]

Attached File

Posted: 1/20/2021 9:10:34 PM EDT

[#17]

@Mad-Machinist

Did you ever figure out if your hybrid bolt will work with a Geissele SSA?

Thanks

Posted: 1/20/2021 9:23:51 PM EDT

[#18]

Foxtrot Mike works.

Posted: 1/20/2021 10:01:09 PM EDT

[#19]

Quote History

Quoted:

I assume your Faxon bolt looks like this one?

https://www.ar15.com/media/mediaFiles/3591/Screenshot_20210118-195057_Chrome_jpg-1785880.JPG

View Quote View All Quotes

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Quote History

Quoted:

Quoted:
min works fine with a faxon bolt.

I assume your Faxon bolt looks like this one?

https://www.ar15.com/media/mediaFiles/3591/Screenshot_20210118-195057_Chrome_jpg-1785880.JPG

just following up as i got the pistol out and took a pic of the bottom of the faxon bolt. its a smooth ramp and should be good to go for any hammer other then the first one i tried

was a parts bin standard GI trigger group that on the hammer had a wide bit that would smash into the carrier part. hence the burr.

Posted: 1/20/2021 10:21:07 PM EDT

[#20]

More detail on mine that do not work.

Attached File

Attached File

So, to be clear....they both work if I pull and release the trigger quickly. If I pull and hold the trigger, then release it only enough to reset.....it doesn't no matter how far I let it go forward.

I know some just say "you need a ramped bolt" but aren't either of these considered "ramped"?

I wish it was that simple with the MBT, (mine is a 2 stage) but I don't think it is that simple.

I hate to order one and have it not work. I may just wait and get a CMMG 8" RDB barrel and bolt again. I have had every length but the 8" at one time....now that is the one I want...OOS everywhere...of course.

Posted: 1/20/2021 10:44:39 PM EDT

[#21]

I found a toolcraft one in stock at a fair price. May try that.

To my eye, my KAW or KAK look so similar to the other ones mentioned...as far as the ramp.

Posted: 1/20/2021 11:02:58 PM EDT

[#22]

Wonder if there is such a small variance in where the hammer pin hole is drilled a smidge high to cause the hammer to drag or something.

Posted: 1/20/2021 11:07:01 PM EDT

[#23]

Very good question.

I have tried these in multiple lowers and with multiple MBTS.

I just ordered a toolcraft bolt. $108 delivered.

Posted: 1/21/2021 11:39:36 AM EDT

[#24]

Quote History

Quoted:
Very good question.

I have tried these in multiple lowers and with multiple METS.

I just ordered a toolcraft bolt. $108 delivered.

View Quote

Please keep us updated. I have been considering a spare bolt.

Posted: 1/21/2021 12:22:57 PM EDT

[#25]

Quote History

Quoted:

Please keep us updated. I have been considering a spare bolt.

View Quote View All Quotes

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Quote History

Quoted:

Quoted:
Very good question.

I have tried these in multiple lowers and with multiple METS.

I just ordered a toolcraft bolt. $108 delivered.

Please keep us updated. I have been considering a spare bolt.

Will do!

Posted: 1/21/2021 1:54:20 PM EDT

[#26]

That’s why I got a trigger that would work with any bolt as opposed to finding a bolt to work with a trigger.
The CMC 9mm drop in does that

Posted: 1/21/2021 2:01:56 PM EDT

[#27]

Quote History

Quoted:
That’s why I got a trigger that would work with any bolt as opposed to finding a bolt to work with a trigger.
The CMC 9mm drop in does that

View Quote

That is exactly what I have done with my dedicated 9mm carbines/pistols.

This particular application is for an SBRd lower that I prefer having the LaRue trigger in.

Posted: 1/25/2021 11:24:55 PM EDT

[#28]

SUCCESS!

The toolcraft 9mm bolt resets the LaRue MBT 2 stage trigger.

Thanks all!

Posted: 1/26/2021 6:04:02 PM EDT

[#29]

Quote History

Quoted:
SUCCESS!

The toolcraft 9mm bolt resets the LaRue MBT single stage trigger.

Thanks all!

View Quote

Where'd you get it from?

Posted: 1/27/2021 2:08:49 PM EDT

[#30]

Test fired today. It works!

I ordered 2 more.

Here

Posted: 1/28/2021 12:51:10 PM EDT

[#31]

Quote History

Quoted:
Test fired today. It works!

I ordered 2 more.

Here

View Quote

Thanks. Ordered one if for no other reason than to have a Glock'd bolt that will also run in a Colt style lower.

The bolt ADCO Glock'd for me years ago is too narrow to work with the double stack/double feed mags so I have to keep a Colt bolt on hand for when I want to shoot 9mm FA in my M16.

If this bolt works with something besides a shitty mil-spec FCG even better.

Posted: 1/30/2021 7:21:08 PM EDT

[#32]

I have a couple of gen4 PSA 9mm AR pistols that take glock mags , all are running MBT1S flat bow triggers without a hitch.

Bought a few ToolCraft 9mm BCG's that I haven't tried yet as they are spares , hopefully they will have no issues with the Larue single stage MBT1S triggers.

Posted: 2/9/2021 11:26:37 AM EDT

[#33]

Quote History

Quoted:

Thanks. Ordered one if for no other reason than to have a Glock'd bolt that will also run in a Colt style lower.

The bolt ADCO Glock'd for me years ago is too narrow to work with the double stack/double feed mags so I have to keep a Colt bolt on hand for when I want to shoot 9mm FA in my M16.

If this bolt works with something besides a shitty mil-spec FCG even better.

View Quote View All Quotes

View All Quotes

Quote History

Quoted:

Quoted:
Test fired today. It works!

I ordered 2 more.

Here

Thanks. Ordered one if for no other reason than to have a Glock'd bolt that will also run in a Colt style lower.

The bolt ADCO Glock'd for me years ago is too narrow to work with the double stack/double feed mags so I have to keep a Colt bolt on hand for when I want to shoot 9mm FA in my M16.

If this bolt works with something besides a shitty mil-spec FCG even better.

Just got my blowback Toolcraft 9mm bolt from WCA and it was a bitch to install in the dirty upper.

Guessing I need to clean the upper so the new BCG can start out with an in-spec upper before gunking it up.

Seems like my old Model 1 Sales Colt bolt, which was Glock'd by ADCO, is cut differently and keeps the upper "scraped free" of carbon build-up in the spots where it actually rides.

The Toolcraft bolt is cut differently on the face and was encountering a ton of resistance ~1/2" out from contacting the breech face.

Once I have it smoothly hand cycling I'll run it on the DDLES Glock lower with mil-spec FCG to ensure it runs as well as my current set-up before slapping the upper on an SBR'd AR lower with a Geissele SSA, mag block, and Colt mags.