Midwest Industries New Professional Armorer's Wrench

[HKGuns]

100% agree! I'd love it if MI did something like this. Pretty much everything that's been used for receiver extension installation and removal has been suboptimal up to this point.

And of course I agree with Ned, barrel blocks for muzzle device work only... Using any Reaction Rod type tool for that task is just asking for trouble IMO.

I made my own to work on Muzzle devices. They're pretty effective, their length helps ensure the barrel doesn't move even enough to tweak the gas block / tube.

[Ned Christiansen]

Good stuff. I saw a pic out of Bushmaster years ago showing a bench-mounted tool that was kinda a blend of the two above tools.

I had not heard that people were shearing pins or damaging receivers but it always was in the back of my mind that "could be". I just don't change that many barrels I guess to statistically have it happen to me. I have a friend in the biz who installs barrels daily and early on actually ripped the threaded front portion out of a few uppers by radically over torquing but I don't believe he ever had an issue with the pin-- to my surprise. I guess I'm not nearly as strong as him because I end every barrel change session with my trying to do just that-- go full gorilla on the wrench to try and destroy the upper. It is already cracked from a blow-up but in maybe 5-6 tries now I cannot rip the end off it!


My own setup for barrel change, even though I have the many available tools for it, is to use my mill vise, some 1-2-3 blocks, and an angle plate bolted to the mill table which I use to clamp the barrel to, to keep the barrel extension from trying to turn. This is an imperfect setup since I'm relying on the thread hookup between the barrel and the extension, but it has worked very well just the same. I will modify my URR to accept a length of gas tube to help with alignment and that'll probably be my default setup from now on.

Again I will say the Bev Block (MagPul) is designed to immobilize both parts.... whether it does it as well or not, I do not have the time to explore as a stand-alone test. Having that big 1" shaft all the way through the upper with the URR sure makes everything seem good and solid.

This is the little secret of who really benefits from me giving a class-- me! As often happens, this time I got a few guys from NY who are new to the AR15 and have climbed the learning curve super-fast by doing tons of research and taking lots of classes, and so, are more up to speed than me on everything new that's out there. Glad they showed me the URR.

Even though Geiselle didn't put the key on top I remain a big fan of the company and always take pleasure in saying "extremely smart people interested in quality and utility way more than turning a buck, who come up with great ideas and turn them into quality products."

One thing about any Rod-type tool I'd like to point out is that I've seen guys using them to install and remove muzzle devices, which in my book is sub-optimal (although admittedly very handy). But there again we are relying upon the thread hookup between barrel and extension to hold up to our efforts. True it should not affect anything because that is one tight threaded joint, but much better to immobilize the barrel itself since that's the part we're working against.

[Disciple]

Nuts. Is there a thread that lists these mistakes that are supposed to be common knowledge?

[556Cliff]

Nuts. Is there a thread that lists these mistakes that are supposed to be common knowledge?

I wish I had started collecting them up as they were posted through the years since the Geissele Reaction Rod came out, I'd have quite a mountain of them by this point if I did.

Fortunately Google searching "broken index pin" or "sheared index pin" usually brings up a lot of them, but not all. Most were posted about on AR15.com of course, so try including that in your search.

The thing that I always found odd was the math showing that the stresses on the indexing pin were pretty much identical no matter if you use a Reaction Rod or a set of clam shell upper receiver vise blocks. but the physical evidence only indicates an obvious and recurring problem with index pins shearing when using the Reaction Rod. You pretty much never hear of pins shearing with upper receiver vise blocks which have been in use for far longer and very likely been used for barrel installation and removal countless more times than the Reaction Rod has by this point.

So either the math is wrong or something in the math isn't being accounted for between the 2 differing tools/methods.

@lysander has done the math indicating that before (I think) and it's far out of my wheelhouse. All I know is that the math doesn't make sense with what I've seen.

[Disciple]

I wish I had started collecting them up as they were posted through the years since the Geissele Reaction Rod came out, I'd have quite a mountain of them by this point if I did.

Fortunately Google searching "broken index pin" or "sheared index pin" usually brings up a lot of them, but not all. Most were posted about on AR15.com of course, so try including that in your search.

I meant other failures waiting to happen rather than more proof of the sheared index pin. I am prepared to take your word on that. It would be good to have a list of common problems to avoid all in one place. It's disheartening to be ignorant of something that is considered "common knowledge" despite reading this forum rather extensively.

[556Cliff]

I meant other failures waiting to happen rather than more proof of the sheared index pin. I am prepared to take your word on that. It would be good to have a list of common problems to avoid all in one place. It's disheartening to be ignorant of something that is considered "common knowledge" despite reading this forum rather extensively.

That's not a bad idea for a thread, I'm not sure if there's one like that out there already or not?

[pinzgauer]

So either the math is wrong or something in the math isn't being accounted for between the 2 differing tools/methods.

On the clamshell the only rotational force on the barrel / barrel extension / index pin is friction from the barrel nut inner face on the barrel flange

Where with the reaction rod approach you have pretty much the whole torque dependent on the index pin stopping the rotation.

Early on the pin issue concern me, I believe I might have even commented way back on this forum about that in some of the early discussions. But some very prominent posters were major advocates, so it was not worth debating.

The Bev block theoretically addresses the pin issue, but in practical use there is more flex than I would like to see.

The BEV block is still a handy / useful / convenient tool to use, especially for occasional armorers as it has other uses as well. If you only have one tool it's not a bad one. But if I installed barrels frequently I would be looking for something more robust, probably something like the MI tool.

Over the years I've adopted the Alexander Arms approach of minimal GI spec torque required to do the job. Since monster torques are not involved installing you can actually get away with just about any of the methods, including the one that uses the two pins in the bottom of the receiver and HDPE blocks.

But that's just me (and AA), and I'm sure we will be out shouted by those who say must you must use extreme torque values. You can get solid lockup and keep it without having significant strains on that joint

Barrel removal is a completely different issue and usually is where people have problems with much higher torque.

[556Cliff]

On the clamshell the only rotational force on the barrel / barrel extension / index pin is friction from the barrel nut inner face on the barrel flange

Where with the reaction rod approach you have pretty much the whole torque dependent on the index pin stopping the rotation.

Early on the pin issue concern me, I believe I might have even commented way back on this forum about that in some of the early discussions. But some very prominent posters were major advocates, so it was not worth debating.

The Bev block theoretically addresses the pin issue, but in practical use there is more flex than I would like to see.

The BEV block is still a handy / useful / convenient tool to use, especially for occasional armorers as it has other uses as well. If you only have one tool it's not a bad one. But if I installed barrels frequently I would be looking for something more robust, probably something like the MI tool.

Over the years I've adopted the Alexander Arms approach of minimal GI spec torque required to do the job. Since monster torques are not involved installing you can actually get away with just about any of the methods, including the one that uses the two pins in the bottom of the receiver and HDPE blocks.

But that's just me (and AA), and I'm sure we will be out shouted by those who say must you must use extreme torque values. You can get solid lockup and keep it without having significant strains on that joint

Barrel removal is a completely different issue and usually is where people have problems with much higher torque.

Here's a thread I'm watching since yesterday on ARFCOM where a guy is having trouble trying to loosen a barrel nut on a BCM upper using a BEV Block. > https://www.ar15.com/forums/General/...ut-/5-2504599/

The amount of people in there that swear by using the Geissele Reaction Rod and that it would be somehow better than the BEV Block for the task of removing a stuck barrel nut is quite mind boggling. Some actually insist that barrel blocks are the better option for the task.

Barrel blocks are the best for muzzle device work, but they're just as bad if not worse than the Reaction Rod for doing anything with the barrel nut. Lets not forget all the issues that Old Bushmaster had with putting out rifles that had canted FSBs because they used barrel blocks for barrel installation. And now the places that are using Reaction Rods over the last few years to install barrels with standard FSBs are constantly having the same FSB cant issue as old Bushmater did... Well duh!

A major issue that's contributed to the immense popularity of the Reaction Rod is the reputation of the places that use it and make it. People are under some weird hypnoses and delusion it seems... KAC and and Geissele just can't do anything less than the best in peoples minds so they turn their brains off in regards to anything they make. And I love Geissele triggers and I like KAC, I'm just not under the spell like so many seem to be.

[Disciple]

On the clamshell the only rotational force on the barrel / barrel extension / index pin is friction from the barrel nut inner face on the barrel flange

What about the friction between the barrel nut and the receiver threads? That is going apply torque to the entire receiver which will press against the pin.

[1168]

I made barrel blocks for muzzle devices, particularly 9mm ones, but I sometimes use my MI-URR because URX4.